Contents

CHAPTER 7: UPPER LAHONTAN BASIN SUMMARY OF FINDINGS 2

CHAPTER 8: UPPER HUMBOLDT PLAINS SUMMARY OF FINDINGS 9

CHAPTER 9: THOUSAND SPRINGS VALLEY SUMMARY OF FINDINGS 21

CHAPTER 10: COLONIZATION OF NORTHERN NEVADA 28

CHAPTER 11: FLAKED STONE PRODUCTION PATTERNS 35

CHAPTER 12: TRANS-HOLOCENE SUBSISTENCE-SETTLEMENT CHANGE IN NORTHERN NEVADA 49

ANTHROPOLOGICAL PAPERS OF THE AMERICAN MUSEUM OF NATURAL HISTORY

Number 101: 405 pp. March 11, 2016

Copyright © American Museum of Natural History 2016

ISSN 0065-9452

http://dx.doi.org/10.5531/sp.anth.0101

Prehistory of Nevada’s Northern Tier: Archaeological Investigations along the Ruby Pipeline

William Hildebrandt, Kelly McGuire, Jerome King, Allika Ruby, and D. Craig Young

Far Western Anthropological Research Group, Inc.

With Contributions by

David Rhode, Jeffrey Rosenthal, Pat Barker, Kaely Colligan, William Bloomer, Albert Garner, Nathan Stevens, Andrew Ugan, Kimberley Carpenter, Laura Brink,Sharon Waechter, Richard Hughes, Tom Origer, Sharlyn Street, and Wendy Pierce

(EPUB PART 2)

CHAPTER 7: UPPER LAHONTAN BASIN SUMMARY OF FINDINGS

Kelly McGuire

The Upper Lahontan Basin includes approximately 119 miles of corridor from where it descends from the High Rock Country into the eastern arm of the Black Rock Desert near Leonard Creek and east to the headwaters of Evans Creek, southeast of Midas, Nevada (fig. 26). As described in chapter 2, this region is generally coterminous with the basin of pluvial Lake Lahontan and exhibits the lowest overall elevation of the four project areas (between about 4000 and 5500 ft). Lake Lahontan’s bed is vegetated with an open mosaic of greasewood, seepweed, saltbush, and shadscale desert scrub; at slightly higher elevations, sagebrush steppe dominates. Major streams and creeks of this region include the Quinn River, which empties into the eastern arm of the Black Rock Desert, the Little Humboldt River north of Winnemucca, and Evans Creek at the eastern end of this project segment.

In total, 67 sites with prehistoric components in this corridor segment received some level of data recovery treatment (fig. 26). Some 111 m3 were hand-excavated during treatment, entailing 77 control units, 124 surface scrapes, and 310 shovel probes (table 31). General surface collection was also done at most sites.

Fig. 26. Upper Lahontan Basin.

Chronological Overview

Of the 67 treated prehistoric sites, 36 contained chronometric data sufficient for component definition. The remaining 31 sites could not be assigned to a component. In all, 41 components are present at these 36 sites, consisting of 32 sites with single components, three with two components, and one with three components.

Table 32 presents a summary of chronological data for Upper Lahontan Basin sites. As the table shows, all major component periods are represented, although the earliest periods (Paleoindian, Paleoarchaic, and Post-Mazama) are not well represented. Perhaps more surprising is the robust Late Archaic representation; that period seems to have been the highpoint of occupational intensity in the Upper Lahontan Basin. This project segment is characterized by a large number of dune fields in the Quinn River area, as well as in Paradise Valley north of Winnemucca, which appear to have been attractive locations during the Late Prehistoric era.

Projectile point frequencies associated with each time period generally corroborate the component frequencies, with the Late Archaic Period exhibiting both the highest absolute and the highest time-standardized frequencies (table 32). However, unlike the component frequencies, projectile point frequencies appear to have ramped up beginning in the Early Archaic Period, rather than the Middle Archaic. The sharp increase in Early Archaic Period occupations is reflected elsewhere across the project area (see chaps. 6 and 8) as well, and may have been a response to improved climatic conditions at the end of the middle Holocene.

A total of 924 obsidian hydration readings was obtained from dated component contexts from Upper Lahontan Basin sites; these data were then standardized according to source and hydration rate, as well as deposition rate (number per 1000 years; table 32). In this case, the time-standardized frequencies jump in the Middle Archaic Period and then peak during the Late Archaic Period. The Terminal Prehistoric standardized frequency drops somewhat but remains comparable to the Middle Archaic Period.

Finally, five radiocarbon dates were obtained from this project segment, ranging between 2460 and 50 cal b.p. (see table 17). Although the sample is small, they tend to corroborate the increase in late Holocene settlement activity indicated by the other proxy data.

Assemblage and Feature Overview

The 41 spatiotemporal components documented in the Upper Lahontan Basin are dominated by flaked stone scatters, which comprise 78% of all components for all time periods (table 33). It is interesting to note, however, that this ratio almost reversed during the Late Archaic Period, with habitation sites comprising 63% of all components. As we have noted, much of the increase in settlement intensity associated with this period appears to have been directed at the many dune contexts found in this lowland setting. Typical of these types of sites are 26HU4792, 26HU4805, and 26HU5153, all located among a series of small dunes near the Little Humboldt River in Paradise Valley. These data suggest that this intensification is associated with increased habitation activity in these contexts.

Features

Eight prehistoric features were documented in this project segment. All are characterized as either charcoal stains or fire-affected rock concentrations, or combinations of the two. Radiocarbon dates of 1620, 1610, and 50 cal b.p. were obtained on three of these features.

Assemblages

Analysis of artifact classes by time period (table 34) shows a distinction between flaked stone tools and ground stone tools with regard to broad subsistence patterns and gender-specific work organization, as described in chapter 3. Virtually all the ground stone recovered from this project segment was obtained from either Middle or Late Archaic contexts, which comports with the component type profiles described above. Paradoxically, there is little evidence of the Terminal Prehistoric habitation observed in several other project segments (see chap. 8); the handful of Terminal Prehistoric components here are bereft of ground stone. High frequencies and a diversity of flaked stone tools were also recovered from Late Archaic contexts; upwards of 10 times the number of bifaces were found in Late Archaic components compared to other contexts. As we have described elsewhere (see chap. 11), most bifaces from the Upper Lahontan Basin are pressure-finished, stages 4 and 5 implements, as opposed to early-stage forms. Broadly speaking, hunting and plant processing both appear to have been important to the Late Archaic Period occupants.

In terms of the broad lithic landscape and tool-stone use associated with the Upper Lahontan Basin, obsidian is the dominant material, comprising more than 76% of the entire flaked stone assemblage recovered from this project segment (table 35). Lesser amounts of CCS were documented (24%); most of this material was recovered from components excavated in the eastern portion of the segment, closer to major CCS quarry zones situated on the Upper Humboldt Plains. The dominant obsidian source groups represented in this segment include Double H and Paradise Valley, followed by Craine Creek and Massacre Lake/Guano Valley (table 36). Paradise Valley obsidian, the easternmost source group, is more abundant in components situated toward the eastern part of the segment, whereas Double H is more common in the western and central regions (see fig. 6). The Craine Creek and Massacre Lake/Guano Valley quarries are situated nearby to the west in the High Rock Country, and are thus more common in assemblages recovered in the western portion of the project segment. There are six other sources with only minor levels of representation, as well as a number of specimens of unknown source origin. Most of these minor source groups are located in the northwestern Great Basin, although a cluster of Mount Hicks obsidian was recovered from a Terminal Prehistoric component at 26HU4808. The Mount Hicks source is located in the Inyo-Mono region almost 300 km southwest of this study corridor. High representation of long-distance, exotic obsidians during the Terminal Prehistoric Period has been observed across the study corridor and has implications for Numic mobility and exchange patterns (see chaps. 14 and 16).

In total, 2596 faunal bone elements and fragments were recovered from sites in the Upper Lahontan Basin (table 37). The sample, however, is uneven, as bone was obtained from only 11 site contexts, of which only six contained robust samples. Almost all the bone assignable to component period is Middle Archaic or younger, with the Late Archaic sample the largest. Noteworthy is the comparatively large sample of bird bone—91% of all project bird bone was recovered from the Upper Lahontan Basin. Most of this is unidentifiable to the species level, although the high percentage of ducks in the identifiable assemblage suggests that a large measure of the unidentifiable fraction is also waterfowl. As we have mentioned previously, the Upper Lahontan Basin is at the lowest elevation of the project segments and contains a number of drainages and bottomlands that at various times may have featured productive wetlands suitable for waterfowl. This is consistent with the small sample of fish bone recovered from these contexts (table 37). With regard to the ratio of artiodactyl-sized mammals to smaller animals, the highest Artiodactyl Index is found in Middle Archaic components (0.41), followed distantly by the Late Archaic (0.09), and then by the Terminal Prehistoric (0.03).

A total of 953 charred seeds was obtained from 73.5 liters of deposit, representing eight flotation samples (table 38). Temporal components included in this sample are limited to Middle and Late Archaic contexts. Confirming the broad wetland orientation of this region, more than 43% of the seeds are either cattail or tule. Furthermore, the representation of these two taxa in the projectwide database is almost wholly confined to the Upper Lahontan Basin. Other major taxa represented in flotation samples from this region include saltbush, goosefoot, canary grass, and wild rye. Comparing the Middle and Late Archaic profiles, we find that cattail and tule comprise only 17% of the Middle Archaic sample, but 84% of the Late Archaic sample. These data clearly suggest a stronger wetland emphasis during the Late Archaic Period.

Summary

The Upper Lahontan Basin exhibits some major differences from the other three regions, owing primarily to its low-elevation setting confined to mostly basins, bottomlands, and adjacent piedmonts. Likely due to its proximity to the shorelines and deltaic environments of pluvial Lake Lahontan, there is some indication of Paleoindian and Paleoarchaic occupation. The overall assemblage profile, however, suggests an increase in habitation activity commencing in the Middle Archaic and peaking during the Late Archaic Period. Both faunal and archaeobotanical profiles indicate a strong orientation toward wetland resources found in these contexts, particularly during the Late Archaic Period. Flaked stone acquisition systems in this region were focused on obsidian, particularly glass emanating from the nearby Double H and Paradise Valley sources. Use of CCS is increasingly evident along the eastern portion of segment near the major source zones of this tool stone in the Upper Humboldt Plains.

CHAPTER 8: UPPER HUMBOLDT PLAINS SUMMARY OF FINDINGS

Kelly McGuire

The Upper Humboldt Plains comprises about 102 miles of pipeline corridor between the Snowstorm Mountains in the west and the Snake Mountains in the east (fig. 27). As described in chapter 2, this region is slightly more elevated (between 5000 and 7000 ft) than the adjoining Upper Lahontan Basin to the west and is characterized by mostly dry sagebrush and sagebrush steppe plant communities with some low-density stands of juniper woodland at higher elevations. The entire area is contained within the Upper Humboldt River watershed, and perhaps the most critical resources in this area are the tributaries of the Humboldt: Marys River, the North Fork of the Humboldt, Pie Creek, and Willow Creek.

Fig. 27. Upper Humboldt Plains.

In total, 145 sites with prehistoric components in this corridor segment received some level of data recovery treatment (fig. 27). Some 246 m3 were hand-excavated, entailing 154 control units, 601 surface scrapes, and 765 shovel probes; additionally, three surface collection units were used, along with general surface collection at most of the sites (table 39).

Chronological Overview

Of the 145 treated prehistoric sites, 67 contained chronometric data sufficient for component definition; the remaining 78 sites could not be assigned to discrete components. In all, 84 components are identified at these 67 sites: 55 sites with single components, nine sites with two components, one site with four components, and two sites with five components.

Table 40 presents a summary of chronological data for Upper Humboldt Plains sites. Along with the standard component designations, there are also several combined time periods (i.e., Early Archaic/Middle Archaic and Late Archaic/Terminal Prehistoric) that are not included on this table. Several chronological trends are immediately apparent, the first being that Paleoindian and Paleoarchaic components are absent, and the Post-Mazama Period is only minimally represented. However, projectile points associated with the Paleoarchaic and Post-Mazama periods were recovered, indicating at least some early visitation to this region (table 40). The low frequency of older components in the Upper Humboldt Plains may reflect the sequence of colonization in the northern Great Basin (see chap. 10), as well as the lack of pluvial lakeshores and marshes that were the focus of these early land-use systems.

In a pattern observed elsewhere along the project corridor, the raw frequencies of components, projectile points, and obsidian hydration readings associated with each temporal period appear to ramp up, commencing in the Early Archaic Period and reaching its highest levels during the Middle Archaic Period. As a broad characterization, land-use intensity in Upper Humboldt Plains dramatically increases at the start of the Early Archaic Period probably due in part to ameliorating climatic conditions associated with the late Holocene, which took hold about 4000 to 5000 years ago.

A somewhat different picture emerges when the raw counts of components, projectile points, and hydration readings are standardized by time (per 1000 years). While the increase in Early and Middle Archaic activity is still very much in evidence, this upward trend now continues through the Late Archaic and Terminal Prehistoric periods, the only exception to this being a slight decrease in the frequency of projectile points during the Terminal Prehistoric Period. To the extent that chronological data associated with each temporal period represent broad proxies for land-use intensity, we conclude that settlement activity in the Upper Humboldt Plains remained high through the Late Archaic and Terminal Prehistoric periods.

A total of 24 radiocarbon dates was obtained from sites located in this region (see table 17). While spanning most of the prehistoric era from the Early Archaic to the Terminal Prehistoric periods, most are confined to the past 1500 years, with two distinct clusters: one in the Late Archaic Period between 1100 and 1500 cal b.p., and the other mostly reflective of the Terminal Prehistoric Period between 100 and 600 cal b.p. Most of these dates were obtained from thermal features that often contained charred seeds and/or faunal remains, suggesting that this kind of processing facility was in ascendance later in time.

In summarizing the chronology of prehistoric occupation in the Upper Humboldt Plains, we observe that virtually all proxies indicate a substantial increase in settlement activity associated with the Early Archaic Period. Certainly this region was used before this time, but visitation seems to have been sporadic and observable only in the smattering of projectile points and occasional hydration readings associated with this era. This increase in settlement activity appears to have been sustained throughout subsequent periods and into the Terminal Prehistoric Period, except with a short break between 1100 and 600 cal b.p. that may be associated with the Medieval Climatic Anomaly (MCA; see chaps. 2 and 10).

Assemblage and Feature Overview

In total, 87 spatiotemporal components are documented in the Upper Humboldt Plains (table 41). Flaked stone scatters comprise 69% of all components for all periods. Perhaps the most relevant measure of land-use patterns is the ratio of flaked stone scatters to habitation components, the latter including both simple and complex habitation sites, as well as sites containing features. The percentage of habitation sites is 27% for the Early Archaic, increases to 40% for the Middle Archaic, dips to 29% during the Late Archaic, and then spikes to 78% during the Terminal Prehistoric Period. The comparatively high percentage of habitation components during the Terminal Prehistoric Period may relate to arrival in the northern Great Basin of Numic speakers with their “family band” settlement organization (see chap. 15).

Assemblages

Analysis of artifact classes by time period (table 42), specifically the distinction between flaked stone tools and ground stone tools, reveals implications for subsistence patterns and gender-specific work organization. The ratio of flaked stone tools (projectile points, bifaces, drills, formed flake tools, and simple flake tools) to ground and battered stone (milling stones, hand stones, pestles, battered cobbles, and miscellaneous ground stone) was highest during the Late Archaic Period, at about 114 to 1.

Conversely, the lowest ratio is 13:1, for the Terminal Prehistoric; i.e., the highest relative frequencies of milling and other processing equipment occur in Terminal Prehistoric components. The Early and Middle Archaic ratios are 45:1 and 24:1, respectively. Broadly speaking, hunting and the production of hunting-related tools appears to have been more important during Middle and Late Archaic times, whereas plant procurement and processing were more common during the Terminal Prehistoric Period. This period is also represented by the highest frequency of thermal features, many used at least in part for plant processing.

Related to late prehistoric occupation are the 102 pottery sherds recovered from seven sites along this region (see table 42). Of those ascribable to type, 91 are Great Basin Brownware sherds dating to the Terminal Prehistoric Period, and 11 thin-walled Great Salt Lake Grayware specimens thought to be associated with Fremont/Late Archaic occupations; the latter were all recovered from 26EK11836. Great Basin Brownware sherds were recovered from the Upper Humboldt Plains and Thousand Springs Valley regions, but not from the High Rock Country or the Upper Lahontan Basin. This distribution mostly mirrors the ethnographic territory of the Western Shoshone. To the extent that pottery may have proved crucial in the processing of seeds (Eerkens, 2004), brownware distribution may also track the relative significance of seed resources to prehistoric inhabitants along the project corridor (see chap. 15).

In terms of the broad lithic landscape and tool-stone use associated with the Upper Humboldt Plains, it is clear that cryptocrystalline silicate (CCS) is the dominant material, comprising 95% of the flaked stone assemblage (table 43). Obsidian is a distant second, representing only 4% of all materials. The easiest explanation for this is that, unlike other project regions, there are no obsidian sources located in the vicinity of this area, but there are a number of CCS outcrops and quarry sites and localities within and proximal to the project corridor, the most famous of which is the Tosawihi quarry located south of the Willow Creek area. Three other, smaller CCS quarry sites were documented within the project corridor, and it is likely that opportunistic tool-stone procurement occurred at any number of CCS exposures found throughout this region.

The primary obsidian source represented in the Upper Humboldt Plains sites is Paradise Valley, followed by Browns Bench/Browns Bench Area (table 44). At least eight other sources are represented in trace amounts (<3.0%), and there are a number of samples of “unknown” source affiliation. This seems to be a case of proximity, as the two primary source groups are located closest to this project segment. Not unexpectedly, given their geographic orientation to this project segment, Paradise Valley obsidian tends to be more prevalent in assemblages in the western part of the segment, whereas Browns Bench is more common in the east.

In total, 4215 faunal bone elements and fragments were recovered as part of the Upper Humboldt Plains excavations (table 45). The sample, however, has very little utility with regard to a regional assessment of hunting practices and subsistence patterns, as more than 78% of these remains were obtained from the Terminal Prehistoric component at 26EK12130. Notwithstanding this severely unbalanced sample, several observations can be made. First, there is a high frequency of artiodactyl remains, dominated by unidentified artiodactyl-sized fragments, resulting in high Artiodactyl Index values for all component periods. Again, this is hardly definitive, but it does suggest the sustained importance of large-game procurement through much of the late Holocene. Also noteworthy is a single bison element from an Early Archaic component at 26EK12105. This element, a phalanx, was radiocarbon dated to 3810 cal b.p., at the very end of the Early Archaic Period.

A total of 1337 charred seeds was recovered from 68 samples, originating from 19 component contexts investigated in the Upper Humboldt Plains. These include 1069 seeds identified to family, genus, or species, and 268 fragments that remain unidentified (table 46). Twenty-two taxa are recognized: the five that dominate are blue-eyed Mary, antelope bush, grass family, dock, and goosefoot. Most of these are late spring to summer ripening seeds from a variety of habitats. Taxon representation is greatest in Late Archaic components, although seed frequencies and densities are higher in Middle Archaic components.

Summary

Unlike the adjoining Upper Lahontan Basin, the Upper Humboldt Plains region of the project corridor contains no Paleoindian or Paleoarchaic deposit, and only a very limited number of Post-Mazama components. The archaeological record of this region really begins near the end of the middle Holocene, during the Early Archaic Period. From there, settlement intensity appears to have increased during each subsequent period, reaching its highest levels during the Terminal Prehistoric Period. Settlements reflecting habitation also increased in number during the Early and Middle Archaic periods, declined slightly during the Late Archaic, and reached their highest percentage during the Terminal Prehistoric Period. We suggest that the brownware pottery found in Terminal Prehistoric contexts in both the Upper Humboldt Plains and Thousand Springs Valley is a marker of the Western Shoshone and that the peak in habitation sites during this period reflects the arrival of these Numic speakers in the region. Unlike the other project regions, the Upper Humboldt Plains is dominated by CCS tool stone. When it is found, obsidian is mostly from the two nearest sources, Paradise Valley and Browns Bench.

CHAPTER 9: THOUSAND SPRINGS VALLEY SUMMARY OF FINDINGS

Albert Garner

The Thousand Springs Valley region includes approximately 54 miles of project corridor, extending westward from the Nevada-Utah border through the southern extent of the Delano Mountains, the northern end of the Toano Range, and the central portion of Thousand Springs Valley, and terminating near the western foothills of the Snake Mountains north of Wells, Nevada (fig. 28). The majority of this region is part of the Bonneville Basin watershed, while the area west of the Snake Mountains drains into the Upper Humboldt River watershed. As noted in chapter 2, the region is set in the northern Basin and Range province, characterized by dissected plains, semiarid hills, mountains, and valleys generally ranging between 5000 and 7500 ft in elevation. The valley floors host greasewood and shadscale communities interspersed with a variety of grasses and sagebrush species, while sagebrush steppe continues into the higher elevations along with scattered juniper woodlands and sporadic occurrences of pinyon pine. The major water sources are Thousand Springs Creek and its tributaries. Small creeks, like Burnt Creek in the western foothills of the Snake Mountains, and springs, like Jackson Spring in the uplands near the Nevada-Utah border, are also notable.

Fig. 28. Thousand Springs Valley.

In total, 40 sites with prehistoric components in this corridor segment received some level of data recovery treatment. Just less than 87 m3 were hand excavated, entailing 77 control units, 166 surface scrapes, and 226 shovel probes; additionally, one surface collection unit was used, along with general surface collection at most of the sites (table 47).

Chronological Overview

Of the 40 treated prehistoric sites, 17 yielded chronometric data sufficient for component definition, while the remaining 23 sites could not be assigned to a component. In all, 26 individual components are present at these 17 sites, consisting of 13 sites with single components, three with three components, and one with four components.

Table 48 presents a summary of chronological data for the Thousand Springs Valley sites. Only one site (26EK12352), represents an occupation prior to 5700 b.p. Standardized by time, the frequency of components per 1000 years gradually increases from the Early Archaic through the Middle Archaic, jumping dramatically during the Terminal Prehistoric Period. Much the same trend is manifested in the number of hydration readings associated with each time period, also standardized by time (table 48). The frequency of projectile points diverges somewhat from the component and hydration trends, with relative decreases during the Middle Archaic and Terminal Prehistoric periods.

Additionally, 36 radiocarbon dates were obtained from this region, ranging between 2750 and 50 (modern) cal b.p. (see table 17). Twenty of these dates were obtained from juniper limb wood associated with a series of antelope traps (see chap. 16); all date to about the past 400 years. The remaining 16 dates were obtained from screen or light-fraction charcoal from archaeological deposits, many from thermal features. Of this total, nine correspond to a Middle Archaic time frame (56%), three are Late Archaic (19%), and four are Terminal Prehistoric (25%).

As we have noted, there is only modest evidence for occupation of this project segment prior to the Early Archaic Period. Most proxy data show a sustained increase in land-use intensity at that time that continued for the remainder of the prehistoric period. The one exception to this general trend is associated with projectile points, which are somewhat more variable, with notable decreases in frequency during the Middle Archaic and Terminal Prehistoric periods. As projectile points are associated with hunting, this could be emblematic of changes in hunting intensity associated with these periods, although the data at hand are hardly definitive in this regard.

The low frequency of older components in the Thousand Springs Valley region may reflect the sequence of colonization in the northern Great Basin (see chap. 10), as well as the lack of pluvial lake shores and large marshes that were the focus of these early land-use systems (pluvial shorelines of Lake Bonneville are situated well east of the study area). Conversely, the dramatic increase in occupation at the start of the Early Archaic Period may be due in large measure to the ameliorating climatic conditions associated with the late Holocene.

Assemblage and Feature Overview

In total, 26 spatiotemporal components are documented in the Thousand Springs Valley region (table 49); especially unique are a series of large antelope trap complexes (see chap. 16).

The sample of components by time period is much smaller than for any other project segment; thus, it is difficult to attribute much significance to changes in component types through time. We note, however, that the overall ratio of habitation components to other component types is similar to that observed in the adjacent Upper Humboldt Plains: earlier components are primarily flaked stone sites (although, one habitation site dates to the Early Archaic), while the number of habitation components increases during the Middle Archaic to nearly the same number as flaked stone sites. This trend continues during the Late Archaic and Terminal Prehistoric periods, where habitation and feature components are dominant. All the trap complexes date to the Terminal Prehistoric Period (see chap. 16).

Features

As previously noted, a variety of features were documented in this region. All are characterized as thermal features or charcoal stains that produced samples suitable for radiocarbon analysis (see table 17). The bulk of radiocarbon dates from features (N = 7) fall into the Middle Archaic and range from 2750 to 1500 cal b.p. Late Archaic feature dates (N = 3) range from 1260 to 740 cal b.p., while a single charcoal sample from a bowl-shaped hearth produced a Terminal Prehistoric date of 310 cal b.p. Interestingly, the three hearth features identified at site 26EK12394 date to different periods: one each to the Middle Archaic, Late Archaic, and Terminal Prehistoric. This pattern could suggest repeated or sustained use of the Thousand Springs Creek floodplain (in the vicinity of modern-day Dake Reservoir) beginning in the Middle Archaic Period and continuing through the rest of the prehistoric era.

Assemblages

Analysis of artifact classes by time period (table 50) reveal certain noteworthy trends with regard to the ratio of flaked stone to ground stone tools for each period. Broadly speaking, this ratio ramps up during the Middle Archaic, where ground stone comprises 13% of the assemblage, remains relatively steady during the Late Archaic at 10%, and then spikes in the Terminal Prehistoric where it comprises 87% of these tools. To the extent that the presence of ground stone within component assemblages is reflective of the activities of women and more generalized habitation, this trend appears to have commenced during the Middle Archaic and become dominant by the Terminal Prehistoric Period; this latter expression perhaps marked the arrival of family residential bands typical of the Numa.

With regard to the lithic landscape of Thousand Springs Valley, cryptocrystalline silicate (CCS) is the dominant tool stone for the flaked stone assemblages for virtually all time periods (table 51). There is, however, a fundamental shift in the preference for obsidian over time. Early and Middle Archaic components are characterized by 35% and 28% obsidian, respectively, whereas Late Archaic and Terminal Prehistoric components contain 7% and 5% obsidian.

The CCS materials identified at sites in this region appear to have been procured both locally and nonlocally. Several tool-stone-quality CCS outcrops and quarries were documented at sites along the study corridor in this region; however, other CCS visually resembles material from distant areas, such as the Tosawihi quarry located on the Upper Humboldt Plains. The local sources include two CCS quarry sites situated on the Nevada-Utah border: sites 26EK651 and 26EK9177/12132 contain bedrock outcrops as well as residual and colluvial deposits of pinkish, reddish, and whitish chalcedony of varying quality. Usable material occurs in low, but uplifted, naturally weathered and fractured outcrops. This allowed for hand removal of large clasts or boulders for assay. Visual similarities in material and texture were identified during analysis, enabling us to link CCS-dominated assemblages with nearby quarries.

The dominant obsidian source represented in the Thousand Springs Valley assemblages is Browns Bench (including Browns Bench Area), which is located 50–70 km north of the project corridor (table 52; see fig. 6). There are, however, observable shifts in conveyance patterns through time. Obsidian samples from Early Archaic and Middle Archaic contexts are almost exclusively from Browns Bench, whereas Late Archaic components contain 36% from other source groups, primarily Malad, more than 200 km distant in southern Idaho, and Topaz Mountain, located more than 250 km to the southeast in Utah. As obsidian became less important later in time (during the Terminal Prehistoric), this trend was also accompanied by a greater emphasis on exotic obsidian from quarries to the east (see chap. 15).

Twenty-five brownware pottery sherds were recovered from this corridor segment. Most of these are from a rock-shelter at site 26EK9178/12133, Locus E, near Jackson Spring, that was otherwise dominated by Late Archaic time markers, suggesting some mixing. Also recovered from this context were several Fremont wares, including Great Salt Lake and Snake Valley Graywares that are more typically Late Archaic. As we review in chapter 15, the Late Prehistoric introduction of brownware pottery is reflected only in the eastern portion of the study corridor and indicates the importance of small seeds during that period.

In total, 5946 faunal bone elements and fragments were recovered from eight components in the Thousand Springs Valley region (table 53). The overwhelming majority of bone (80%) was obtained from Late Archaic contexts at a single site, 26EK9178/12133, Locus E, with much smaller amounts from Middle Archaic deposits at site 26EK11808, and traces of fauna from other dated contexts. Large-game procurement is well represented in all periods, with the Artiodactyl Index approaching 0.45 for Late Archaic components and 0.39 for Middle Archaic contexts.

A total of 577 charred seeds was obtained from 385 liters of deposit, representing 48 flotation samples from the Thousand Springs Valley (table 54). Temporal components represented by viable seed counts are confined to the Early, Middle, and Late Archaic periods, with the bulk of identifiable materials coming from Early Archaic contexts. Twenty-one separate taxonomic categories are recognized in the small-seed assemblage; the most dominant are goosefoot and various grasses. Also found were a number of juniper nut fragments (table 54). With respect to temporal trends, generic grasses predominate in Early Archaic samples, whereas goosefoot is more common in Middle and Late Archaic contexts. Juniper nut fragments are confined mostly to Late Archaic samples. Interestingly, the only tobacco seed obtained from the entire study corridor was recovered from Locus E at 26EK9178/12133, perhaps indicating a ceremonial activity not tied to subsistence.

Summary

As is the case for the other eastern project region (the Upper Humboldt Plains), the Thousand Springs Valley region is, with the exception of a few older projectile points, lacking in evidence of occupation prior to the Early Archaic Period. Starting at the end of the middle Holocene, there was a sustained increase in land-use intensity that continued for the remainder of the prehistoric period. The representation of ground stone tools in project components shows a similar trend, for the most part increasing in relationship to flaked stone tools with each successive period. These tools appear to have been used mostly for the processing of small seeds, predominately grasses and goosefoot. The documentation of brownware pottery may also relate to this increasing reliance on small seeds. While the use of CCS flaked stone predominates during all periods, major shifts in tool-stone procurement are documented for the Middle–Late Archaic transition. Components dating before this time exhibit higher use of obsidian, primarily Browns Bench glass. Communal hunting was clearly important during the Terminal Prehistoric, as suggested by the four trap complexes identified within the study corridor (see chap. 16). Although the faunal assemblage from this segment is both limited and unevenly distributed, the data at hand indicate that artiodactyl hunting was also important during the Middle and Late Archaic periods.

CHAPTER 10: COLONIZATION OF NORTHERN NEVADA

William Hildebrandt and Allika Ruby

The Ruby Pipeline corridor provides a rare opportunity to monitor the Native settlement history of northern Nevada. It crosses through a variety of regions with differing economic potentials and contains an archaeological record spanning at least 13,000 years. These data sets allow us to discover which places were favored by the first Native Americans to reach the region, and how the remaining areas were infilled by people as their populations increased over the millennia.

Several recent studies have used ideal free distribution models (IFD) to help explain the prehistoric colonization and settlement of a variety of parts of California (Kennett et al., 2009; Winterhalder et al., 2010; Codding et al., 2012; Codding and Jones, 2013), and we feel that this approach is appropriate here as well. The basic model proposes that differing habitat types vary in their suitability for habitation based largely on differences in their subsistence returns. It also proposes that the suitability of these habitats will decline as human population densities increase, because increased competition for resources lowers people’s ability to obtain them.

Based on this model, initial colonizers should occupy the highest-ranked habitats first (fig. 29) and stay there until human populations increase to the point (A) where suitability decreases to a level that is equal to the second ranked habitat (H2). As populations continue to grow, reaching the next threshold (B), lower ranked habitats should fill in (H3) and do so in the rank order of their suitability/productivity. Even after multiple habitats have been infilled over time, either through local population growth or in-migration, the highest-ranking habitats should always have higher population densities due to their higher level of suitability/productivity.

Fig. 29. Ideal free distribution model (from Kennett et al., 2009).

As summarized by Codding and Jones (2013: 14569), “the IFD provides two main qualitative predictions: (1) the most suitable habitats should always be occupied first; and (2) they should always have the highest population densities.”

Habitat Variability

As outlined in chapter 2, the project corridor traverses four major regions: the High Rock Country, the Upper Lahontan Basin, the Upper Humboldt Plains, and Thousand Springs Valley. These areas are generally composed of a sea of sagebrush-grass steppe, but there are key differences among them that may have influenced the intensity of settlement over time. Most of these differences in habitat are due to variable amounts of effective moisture based on elevation and relationship to winter storm systems originating in the Pacific Ocean, and the nature of local soil conditions (e.g., volcanic lithosols versus old lake-bed sediments). Because of the large size of and internal variability within each of the regions, we make no attempt to formally quantify these differences. Instead, the following discussion provides a qualitative assessment of habitat productivity, and these assessments are evaluated with quantitative patterns produced by the archaeological record. More detailed descriptions of the regions are provided in chapter 2.

The High Rock Country is generally better watered than most of the other regions, due to its higher elevation and proximity to winter storms originating from the Pacific. These relationships result in sagebrush steppe and juniper woodland habitats with high quality browse and grazing for large game, and cool-season grasses mixed with more typical Great Basin species. Probably most importantly, however, are the vast tracts of high lava plains that produce copious amounts of root crops, especially epos (yampah), along the western end of the corridor at Barrel Springs. The importance of this area is supported by Fowler and Liljeblad’s (1986: 437) ethnographic study of the Northern Paiute, where this area is highlighted as one of the few population concentrations in northern Nevada (see also chap. 3).

The Upper Lahontan Basin is warmer and drier than the High Rock Country, because of its lower elevations and more easterly location. Much of the habitat is composed of old lake-bed deposits and adjacent slopes originally associated with Pleistocene Lake Lahontan. These low-lying areas are composed of arid greasewood-saltbush scrub associations, which are not conducive to populations of large game but do produce important small-seeded plants like Indian rice grass, tansy mustard, and many others. Moving out of the basin into higher elevations, substrates with rocky soils produce dry-adapted root crops like bitterroot and mariposa lily. As in the High Rock Country, Fowler and Liljeblad (1986: 437) identify the Quinn and Little Humboldt rivers as areas with relatively high population densities.

Elevations increase again in the Upper Humboldt Plains, creating greater annual precipitation than in the Upper Lahontan Basin. Most of this area is vegetated by dry sagebrush or sagebrush-steppe communities. Several important grasses and other small-seeded plants exist here, and some dryland slopes produce root crops including bitterroot, epos, and biscuit-root. Although the corridor bypasses most upland areas, nearby mountain peaks reaching nearly 10,000 ft are important habitats for artiodactyl populations. These mountains also feed several permanent tributaries of the Humboldt River that contain fish and support riparian habitats where camas and tobacco root grow, and provide forage for large game populations. Steward (1938: 152–154) identifies the Humboldt River valley as one of the most fertile habitats in northern Nevada, but he does not identify any Western Shoshone winter villages or population concentrations along the project corridor.

Elevations progressively drop as we cross the Thousand Springs Valley, reducing precipitation. Due to the valley’s easterly location, up to 25% of the annual rainfall occurs as monsoonal thunderstorms during the summer. Lower-lying areas are dominated by communities of greasewood-saltbush scrub where small-seeded resources are particularly abundant. These habitats were also conducive to antelope populations, evidenced by the large number of traps found in the region (see chap. 16). The project corridor avoids most upland areas, but many are covered by juniper woodland, and some contain pinyon as well. Western Shoshone populations appear to have been rather small throughout the region, as no villages or population concentrations are identified by Steward (1938: ix) along the corridor. He does, however, note a few villages along Thousand Springs Creek and near Montello, south of the corridor.

As outlined in chapter 2, a great deal of change occurred between the late Pleistocene and the Terminal Prehistoric Period. During the Paleoindian Period (14,500–12,800 cal b.p.), rapid warming associated with the Bølling-Allerød Interstadial brought a decline in Pleistocene pluvial lake levels. With the beginning of the Paleoarchaic Period (12,800–7800 cal b.p.) and the Younger Dryas interval, colder conditions returned and lakes recharged until about 11,700 cal b.p., when warmer conditions took hold again. While all parts of the corridor probably benefited from periods of increased effective moisture, areas with lake basins (e.g., Parman Basin in the High Rock Country) may have had relatively higher levels of productivity than other places, due to the development of marshland habitats.

As aridity increased during the latter end of the Paleoarchaic and into the Post-Mazama Period (7800–5700 cal b.p.), habitat suitability was probably depressed everywhere, but upland areas adjacent to the corridor may have been relatively more productive than other locations. Drought conditions ameliorated during the Early (5700–3800 cal b.p.) and Middle (3800–1300 cal b.p.) Archaic periods, except for persistent droughts between about 2600 and 2000 cal b.p. With the exception of this dry interval, the productivity of all habitats improved during these periods of increased effective moisture, and it seems likely that many of the environmental patterns we see today began to take shape at this time.

Severe drought conditions occurred again during the Late Archaic (roughly between 1100 and 700 cal b.p.) as part of the Medieval Climatic Anomaly (MCA), producing lower habitat suitability everywhere. As with the arid periods during the middle Holocene, a limited number of well-watered areas within and adjacent to certain upland areas may have served as refugia. Finally, effective moisture increased during the Little Ice Age after 600 cal b.p. and improved conditions continued through the Terminal Prehistoric Period, with habitat productivity similar to modern times.

Discussion

Although there is a great deal of environmental similarity across the Northern Tier of Nevada, there are some important differences in resource productivity along the study corridor. First, the High Rock County is obviously highly ranked with its relatively high effective moisture, artiodactyl populations, and root crops. This ranking may have been particularly high early on, when upland basins held marshland habitats. It is also important to note that the western end of the High Rock Country supported high population densities during the ethnographic period.

The Upper Humboldt Plains also has relatively high effective moisture, a large number of perennial streams, and a good potential for root crops. Artiodactyls are also abundant in nearby upland areas but not immediately along the project corridor. Resource productivity seems lower in the Upper Lahonton Basin due to its lower precipitation, and lower frequency of perennial streams, root crops, and artiodactyls. It does, however, have abundant small-seeded resources. Finally, Thousand Springs Valley also has low overall productivity with exception of its small-seeded resources and potential for significant antelope populations; in addition, the ethnographic record identifies no population concentrations in the local area.

Although these differences could be used to rank the four regions and develop a series of predictions following the expectations of the IFD model, the coarse-grained nature of the subsistence productivity measures make it prudent to avoid this level of formality. Instead, the following presentation simply presents a series of land-use indicators across the four regions and observes how these zones were initially colonized and ultimately filled in over time.

Land-Use Indicators

Four data sets are used to monitor the settlement history of the four regions and of the project corridor as a whole. We begin with the frequency of time-sensitive projectile points from surface contexts only, followed by an analysis of the time-space distribution of single-component areas. The component areas were defined by some combination of projectile points, radiocarbon dates, obsidian hydration readings, and in a few cases, pottery sherds and beads. We then present a short discussion of ground stone tools recovered from the single-component areas. Finally, we present the radiocarbon dates obtained during the project, using only one assay per single-component context.

Projectile Points

Temporally diagnostic projectile points provide one avenue for tracking human land-use through time, and changes in point frequencies are commonly interpreted as proxy measures for changes in regional human population densities (see Bettinger, 1999, 2015). Because projectile points were typically used for hunting, however, some have argued that they are a better measure of hunting intensity and less related to human population densities (see Hockett, 2009, 2015). While we appreciate the latter point, and will consider it below, we find their time-space distributions to be quite meaningful with regard to land-use histories, especially when combined with the other measures used in this study.

Our projectile point data are limited to temporally diagnostic types collected from surface contexts; although the function of crescents is debated, they are included in this dataset (table 55). The resulting assemblage was retrieved from sites (N = 1134) and isolated contexts (N = 50). To correct for the differential amount of time that each point type was used, and differences in the area of land encompassed by the four regions, these data have been converted to the frequency of points per 1000 years of time and per 1000 acres of land (table 56).

All five of the small sample of Great Basin Concave Base points (Paleoindian Period) were found in the High Rock Country (table 56; fig. 30). The overall density of Great Basin Stemmed points (Paleoarchaic Period) increases by a factor of 4.0 (0.1 versus 0.4; table 56) and they still occur mostly in the High Rock Country (75%), with a few trickling out into some of the other regions. All four of the crescents recovered on this project are from the High Rock Country, further supporting early occupation of this region.

Fig. 30. Percentage of key surface-collected projectile points by region, based on the number deposited per 1000 years and 1,00 acres of land.

Densities increase again (by a factor of 5.5) with Northern Side-notched points (Post-Mazama) and, continuing the preceding trend, the High Rock Country shows the highest density (5.4). Humboldt/Gatecliff points largely correspond to the Early Archaic Period, but we expand the length of their occurrence to a limited degree because many Humboldt points are found in earlier contexts (see chap. 5). Overall densities of these types increase again by a factor of 3.4, and again the High Rock Country accounts for the largest proportion (16.7), followed by a minor switch in the ordering of the Upper Lahontan Basin (4.2) and Upper Humboldt Plains (6.4); Thousand Springs Valley (2.5) continues to its lowest density status. Projectwide densities remain essentially the same during the Middle Archaic Period, so the IFD model would predict that the relationship between the four ecosystems should also remain the same. This expectation is met, as the proportion and rank order of projectile point densities are quite similar across the region.

If the most suitable habitats should always be occupied first, and these habitats should always have the highest population densities (Codding and Jones, 2013: 14569), the above data show that the High Rock County was the highest-ranking region during the Paleoindian through the Middle Archaic periods. The Upper Lahontan Basin and Upper Humboldt Plains are similar to one another (the latter perhaps ranking somewhat higher), while the Thousand Springs Valley consistently lags behind.

This trend begins to shift during the Late Archaic Period. Rosegate projectile point densities make a major jump (increase by a factor of 2.3), but their mix across the project corridor changes significantly from what came before. The main change is an abrupt increase in the density of these artifacts in the Upper Lahontan Basin (25.7), which is nearly equivalent to that in High Rock Country (25.3). The rank order of the other two regions, however, remains the same.

Much more radical violations of the original trend appear in the Terminal Prehistoric Period sample with Desert Series projectile points. First, their overall density drops nearly in half, which is surprising given previous models regarding the expansion of Numic peoples late in time (i.e., that it was partially fueled by higher population densities). Second, if population densities did decrease, we would expect the distribution of projectile points to revert back to what appear to be the higher-ranked habitats, producing a pattern similar to that exhibited during the Middle Archaic Period, as the overall density of material from the two time periods is similar. This does not occur: the Upper Lahontan Basin has the highest density of projectile points (9.7), followed by the Upper Humboldt Plains (8.8) and the High Rock Country (6.0). Thousand Springs Valley maintains the lowest density of points (2.9), as it does throughout the sample.

Rather than signaling declining human population levels, the decline in projectile point deposition during the Terminal Prehistoric Period may reflect a different approach to large-game hunting by Numic peoples. The newly arrived Numa were organized into small family-based bands that moved frequently as a group, and tended to create less evidence for specialized hunting camps than was the case during the preceding time periods. Numic groups did participate in communal hunting drives, but, unlike earlier drive sites (Hockett and Murphy, 2009), many of the Numic sites lack projectile points (Jensen, 2007; see also chap. 16), which might also contribute to the perception of declining human populations in the region.

Components

We now turn our attention to the frequency of single-component areas across time and space. Almost 400 such areas were identified (table 57). These data differ from the projectile points in that they come only from sites, and most of them were discovered through excavation. They also represent a broader range of settlement activity, expanding beyond the probable hunting focus reflected by the points.

The density of components per 1000 years and 1000 acres of land is presented in table 58. As with the projectile point data, almost all of the Paleoindian (89%) and most of the Paleoarchaic (83%) components are found in the High Rock County (fig. 31). Component densities nearly double when we move into the Post-Mazama Period (0.7/1000 years). They stay relatively high in the High Rock Country (2.1 components per 1000 years per 1000 acres) during this interval, but also begin to increase in the Upper Lahontan Basin (0.6) and the Upper Humboldt Plains (0.3). Overall densities increase 370% in the Early Archaic Period (2.5 per 1000 years/acres), but the relationship between the regions shifts, such that the Upper Lahontan Basin (0.4) and the Upper Humboldt Plains (1.8) shift their rank order, similar to what we see with the projectile points (see table 56); the High Rock County remains dominant (7.3) and Thousand Springs remains rather low (0.6). Component densities increase only slightly in the Middle Archaic Period, also similar to the projectile point trends, and the relationship among the regions remains the same.

Fig. 31. Percentage of single-component areas per 1000 years and 1000 acres of land.

Overall densities increase by a factor of only 1.2 in the Late Archaic Period, and the rank order of the regions is preserved, but the components are more evenly distributed across the four regions. The density of components in the High Rock Country drops to a level nearly equal to that in the Upper Humboldt Plains, while that of the Upper Lahontan Basin more than doubles relative to its Middle Archaic density, although it is still low. The density of Thousand Springs Valley components remains essentially unchanged.

Major changes occurred again with the arrival of the Terminal Prehistoric Period. First, unlike the density of projectile points (which dropped by nearly half), the density of Terminal Prehistoric components (3.0 per 1000 years/acres) is only slightly lower than that of the Late Archaic Period (3.4 per 1000 years/acres). This finding supports the hypothesis that the extreme drop in projectile point densities is at least partially due to a change in large-game hunting strategies. Second, component densities lessen in the High Rock County (1.3) and Upper Lahontan Basin (1.1), and increase in the more easterly Upper Humboldt Plains (5.6) and Thousand Springs Valley (3.8) regions. Like the projectile points, these findings reflect a total reorganization in settlement pattern and major changes in how people viewed the economic potential of these environments.

Ground Stone

Ground stone implements typically signify plant processing and can be used to monitor resource intensification, and how these activities changed over time and space. The data presented here consist of 101 ground stone tools recovered from single-component surface contexts across the project (table 59). They demonstrate a striking west-to-east pattern of deposition through time that is consistent with the trends of the other data sets. Ground stone was initially confined to the High Rock Country, appeared in the Upper Lahontan Basin in the ensuing Post-Mazama Period, was used on the Upper Humboldt Plains in the Early Archaic Period, and appeared in the Thousand Springs Valley by the Middle Archaic Period. When time averaged, the resulting densities per 1000 acres of land demonstrate a steady progression in artifact deposition until the peak in the Middle Archaic Period, driven largely by a sharp increase of ground stone in sites within the High Rock Country (table 60). By the Terminal Prehistoric Period, ground stone was confined to the Upper Humboldt Plains and Thousand Springs Valley, where we also find more single-component areas (see table 58).

Radiocarbon Dates

Sixty-nine radiocarbon dates are used for this analysis (table 61; fig. 32). They represent the entire sample obtained during the project (see chap. 5), minus those from the antelope traps, modern dates, and duplicate dates from single-component areas. This data set is more limited relative to the projectile point and component data, because of the lower number of observations, the low frequency of assays predating the late Holocene, and the low number of dates from the Upper Lahontan Basin (N = 4). Previous researchers have experienced similar difficulties in obtaining radiocarbon dates from early and middle Holocene contexts, probably because dateable materials from these eras are less likely to be preserved due to destructive processes such as erosion and weathering (Surovell and Brantingham, 2007; Surovell et al., 2009). Thus, the frequency of dates tends to be heavily weighted toward the later eras. Before moving forward, however, it should be noted that Louderback et al. (2011) have summarized a significantly larger sample of nearly 1000 radiocarbon dates from the Bonneville Basin, Fort Rock Basin, and Western Lahonton Basin. This larger data set provides a much higher level of resolution for the early and middle Holocene than is available form the current project corridor.

The paucity of dates from the Upper Lahontan Basin appears to be related to the low density of identified single-component areas in this region throughout the sequence (see table 58), which is linked to the low frequency of residential sites here, as well (see chap. 7). Although they are included in table 61 (also see fig. 32), the Upper Lahontan Basin dates figure little in the discussions that follow.

Fig. 32. Radiocarbon-dated locations by region and time period.

Despite these sampling issues, the distribution of radiocarbon dates across time and space show some similarities with the patterns produced by the projectile points, single-component areas, and ground stone (table 62). First, all three assays predating 7000 cal b.p. are from the High Rock Country. Dates corresponding to the Early Archaic Period are most common in the Upper Humboldt Plains (N = 4; 0.11 per 1000 years/acres). The overall frequency radiocarbon dates jumps by a factor of 3.2 in the Middle Archaic (table 62), with the greatest frequency in the High Rock Country (0.20 per 1000 years/acres), the Upper Humboldt Plains second (0.14 per 1000 years/acres), and Thousand Springs Valley (0.12 per 1000 years/acres) and the Upper Lahontan Basin (0.06 per 1000 years/acres) represented for the first time. All but one of the Thousand Springs Valley dates fall at the end of this interval (i.e., after 2000 cal b.p.), however.

The overall density of radiocarbon dates doubles in the Late Archaic sample and shows a more even distribution across the High Rock Country (0.36), the Upper Humboldt Plains (0.36), and Thousand Springs Valley (0.29). This finding is consistent with the component-area data presented above. Despite the overall increase in assays, it is important to note that there is a major drop between 1000 and 600 cal b.p., probably corresponding to the MCA (see fig. 32).

Unlike the patterns produced by the projectile points and the component areas, the density of radiocarbon samples increases again (almost doubling), peaking in the Terminal Prehistoric. Their distribution across the regions is similar for this latest prehistoric period.

Summary and Conclusion

The data sets we have reviewed here indicate that the High Rock Country was the highest-ranked region until the very end of the prehistoric record. Projectile point densities increased across the entire project corridor over time, remaining dominant in the High Rock Country but progressively increasing in the other regions as well. This general finding indicates that when human population densities were low, people focused most of their foraging activities in the High Rock Country, where key resources like large game and root crops were more abundant than elsewhere. As human population densities in the High Rock Country reached levels that lowered return rates for local resources to a level equal to those in the Upper Humboldt Plains and Upper Lahontan Basin, people started using those areas more than they had before. They also incorporated resources with lower return rates, as signaled by the steady increase in plant processing tools.

Projectile point densities dropped almost threefold during the Terminal Prehistoric Period, but rather than seeing a shift in their distribution back to the High Rock Country—which would be expected with lower human population densities—there was a radical reordering of habitat use, with the High Rock Country ranking third behind the Upper Lahontan Basin and Upper Humboldt Plains. These findings lead us to hypothesize that the drop in projectile points may have been more strongly linked to a shift in large-game hunting strategies and a broadening of the diet breadth, which included use of a greater variety of resources zones, rather than to a major drop in human population densities.

An analysis of the time-space distribution of single-component areas provides support for this proposal, as reorganization of land-use preferences (as signaled by projectile points) also occurred, but there is only minor evidence for a decline in population density during the Terminal Prehistoric Period: component densities dropped by only 14%, compared to a drop of nearly 300% among the projectile points. Although we fully appreciate the taphonomic issues associated with composite samples of radiocarbon dates, this dataset also suggests no major population decline.

These data indicate that hunting (and probably epos collection) was a high priority during much of prehistory—and that much of it took place in the High Rock Country. This focus on hunting can be seen by the high number of specialized flaked stone scatters that dominate the project corridor prior to the late Holocene (see chap. 11) as well as by the greater numbers of projectile points that predate the Late Archaic Period. With the onset of the late Holocene, particularly during the Middle Archaic Period, use of the corridor diversified, as habitation sites (e.g., those with milling gear) increased in frequency and people spread out into a wider range of habitats. This general progression, which is fully consistent with the IFD model, reached a zenith sometime during the Late Archaic but broke down thereafter. This violates the IFD predictions that (1) the most suitable habitats should always be occupied first; and (2) those habitats should always have the highest population densities, especially the latter. Instead the data seem to indicate a reorganization of the habitat ranking with the arrival of the Terminal Prehistoric Period. What would have caused such a reorganization? Why would the High Rock Country become less suitable?

If the decline in projectile points reflects a decline in large-game hunting opportunities, this could explain the change in habitat preference/ranking. Using a strictly ecological perspective, we might argue that human population increases led to the depletion of large game across northern Nevada, lowering the productivity of hunting (and the importance of the High Rock Country) and catalyzing greater focus on alternative resources and resource zones. But there is little evidence for a population explosion during the Terminal Prehistoric Period large enough to maintain such a level of exploitation. In fact, much of our data shows that human population densities may have been slightly lower at this time.

Instead, a series of historical contingencies, one environmental and one cultural, provide a better explanation for these changes. Several researchers have argued that the MCA disrupted human adaptations throughout the American West (Berry and Berry, 1986; Madsen, 1989; Larson and Michaelsen, 1990; Jones et al., 1999; Grayson, 2011; McGuire et al., 2013), and severe droughts associated with this interval could have adversely affected northern Nevada as well (see chap. 2). The major break in the radiocarbon record outlined above corresponds to this interval (see the 1000–600 cal b.p. interval on fig. 32) and may represent a disruption in settlement across much of the project corridor.

The reorganization of habitat preference and settlement patterns that we observe in our data corresponds to the second historical contingency—the northern spread of Numic-speaking peoples across much of the western Great Basin. Although the timing of their arrival is debated (Hildebrandt and King, 2002; Delacorte, 2008), there is general agreement that Numic peoples practiced an adaptation fundamentally different from the people who occupied the region before them. They tended to live in smaller, dispersed family groups that were more reliant on small-seeded resources, with the harvesting of these foods facilitated by the development of the seed beater and the triangular winnowing tray (Bettinger and Baumhoff, 1982). This change in adaptation was also accompanied by shifts in settlement patterns similar to those observed in our study, as people spread into new habitats that had rarely been used before (Delacorte, 2004; McGuire and King, 2011; McGuire et al., 2013). A more detailed assessment of these proposed land-use pattern changes will be presented in the chapters that follow, giving particular focus to the artifact assemblages and subsistence remains recovered from the project sites.

CHAPTER 11: FLAKED STONE PRODUCTION PATTERNS

William Hildebrandt, Kaely Colligan, and William Bloomer

Previous research in the Great Basin has identified a great deal of variability in how prehistoric peoples obtained and used tool stone over the millennia. Several scholars have noted that Paleoindian and Paleoarchaic foragers practiced a high degree of residential mobility, visiting widely dispersed quarries during their travels. This pattern of settlement is reflected archaeologically by high levels of tool-stone source diversity (particularly among projectile points) as people discarded worn-out implements made from distant sources of stone and replaced them with new tools when they encountered new sources (Jones et al., 2003, 2012; Smith, 2010; Beck and Jones, 2011).

Settlement mobility appears to have decreased significantly during the Early and Middle Archaic periods; this is reflected by reduced levels of tool-stone diversity and the emergence of substantial residential bases (McGuire, 2002; McGuire and Hildebrandt, 2005; Smith, 2010, 2011). Although there is some debate regarding the degree of settlement stability that developed at this time (Delacorte and Basgall, 2012), it seems clear that these land-use pattern changes were accompanied by a rise in logistical mobility. The latter is reflected by intensive hunting in distant high-elevation areas for the first time and special visits to major obsidian quarries where artisans produced bifaces not only for their own use, but for exchange with neighboring peoples as well. This surplus production for exchange is most pronounced at quarries along the Sierran-Cascade Front, adjacent to the large consumer populations living across the mountains in cismontane California (Hall, 1983; Hildebrandt et al., 1994; Gilreath and Hildebrandt, 1997, 2011; Ramos, 2000; Hildebrandt and McGuire, 2002; King et al., 2011).

This system of obsidian production and exchange appears to have crashed during the latter half of the Late Archaic and into the Terminal Prehistoric Period. Most quarries show little or no evidence of production, and obsidian becomes rare in the archaeological record of outlying areas where it was once abundant. In most of these places, local tool stone became more important. This is usually marked by a higher frequency of cryptocrystalline silicate (CCS) stone, or by quantities of obsidian from low-quality pebble sources scattered across the landscape. The reasons for the collapse in obsidian production and exchange are not entirely clear, but most researchers think it resulted from two main factors: social and economic disintegration stemming from the Medieval Climatic Anomaly (MCA; Jones et al., 1999; Moratto, 2011), and the reduced need for tool stone with introduction of the bow and arrow (Gilreath and Hildebrandt, 1997, 2011; Hildebrandt and McGuire, 2002; Delacorte, 2004).

Previous work in northwestern Nevada and northeastern California has shown a different set of patterns, especially during the latter end of the sequence (McGuire, 2002; Smith, 2010; Smith et al., 2012). Although actual production intensity could not be measured because they were not working in quarry areas, these studies did not reveal the contraction of flaked stone procurement zones outlined above. Instead, transport distance of obsidian artifacts actually increased after 1000 cal b.p., indicating that interregional exchange may have also increased at this time.

The current project corridor provides an outstanding opportunity to study these alternative senarios, as it passes through a variety of lithic landscapes, some with obsidian and some without. As outlined above (see chap. 2), the western end of the corridor lies adjacent to multiple obsidian sources, including substantial Massacre Lake/Guano Valley quarry areas, while in the east obsidian sources are much fewer and more distant. The eastern area is also close to large concentrations of CCS stone, including the well-known Tosawihi chert quarries located only 10 km to the south along the Upper Humboldt Plains.

We begin our discussion with a general review of tool-stone use across the project area, documenting changes in the availability and use of obsidian along the corridor. Next, we measure the intensity of obsidian production, using obsidian hydration data from across the project corridor to determine whether there were any particular places or times when flaked stone production reached peaks similar to those outlined above. Finally, we present a technological analysis of the flaked stone tools and debitage, giving special attention to variations in biface reduction strategies across time, space, and material type.

Lithic Landscapes and Variability in Tool-stone Use

Obsidian and CCS account for almost all the tool stone used across the project corridor. Although some fine-grained volcanic materials were used (e.g., basalt), 95.5% of the projectile points (which tend to have high source diversity) were made from obsidian and CCS.

The west-to-east variability in tool-stone availability is easily seen by comparing the frequency of obsidian versus CCS recovered from the Ruby Pipeline sites (table 63; fig. 33). Combining all time periods, flaked stone tools and debitage from the High Rock County are dominated by obsidian (97%). Obsidian remains important in the Upper Lahontan Basin (74%) but drops significantly thereafter, accounting for only 6% of the Upper Humboldt Plains assemblages (partially due to the proximity of the Tosawihi chert quarries) and 16% in the Thousand Springs Valley.

Fig. 33. Relative frequency of obsidian and cryptocrystalline silicate (CCS) tool stone along the project corridor.

From a projectwide chronological perspective, obsidian maintains a strong dominance during the Paleoindian, Paleoarchaic, and Post-Mazama periods (90% to 95%), drops in the Early Archaic (53%), increases again the Middle Archaic (82%), and trends downward in the Late Archaic (42%) and Terminal Prehistoric (5%) periods (table 63; fig. 34). At first glance, this shift from obsidian to CCS material in late prehistoric times is consistent with the generalized pattern of people relying more on lower quality, local materials. But it is important to emphasize that much of this trend was heavily influenced by how the project area was sequentially populated in a west-to-east fashion through most of the Holocene (see chap. 10). That is, as human populations continued to infill the less productive eastern portions of the project corridor, where obsidian was also less abundant, the overall importance of obsidian relative to CCS materials decreased over time.

Fig. 34. Relative frequency of obsidian and CCS tool stone by time period.

Before moving on, however, we should note that there is some minor evidence for localized shifts from obsidian to CCS that are not related to the macrosettlement changes outlined below (table 64). Beginning in the Thousand Springs Valley, components dating to the early and middle Holocene (Paleoindian, Paleoarchaic, and Post-Mazama) have relatively high contributions of obsidian (64%) compared to those dating to the Early and Middle Archaic periods (33%), and late prehistoric times (7%). A similar pattern is exhibited in the Upper Humboldt Plains, where obsidian makes up 7% of the early and middle Holocene assemblages, 10% of those dating to the Early and Middle Archaic, and 2% in late prehistoric contexts. This progression is unilinear in Upper Lahontan Basin (95% to 92% to 69%), while obsidian use remains high throughout the sequence in the High Rock Country (97% to 96% to 99%).

Similar to the relationship between obsidian and CCS, the mix of obsidian types also shows a high level of variability across the project corridor (table 65; fig. 35). Eight geochemical sources account for 85% of the obsidian that was used, and some combination of them dominates across all four regions. Beginning in the west, the High Rock Country includes a substantial amount of Massacre Lake/Guano Valley (46%), followed by lesser amounts of Craine Creek (20%), Nut Mountain (16%), Mosquito Lake (10%), and Bidwell Mountain (8%), and little or none of the other three primary sources.

Fig. 35. Relative frequency of the primary obsidian sources along the project corridor.

Obsidian source composition changes significantly when we move to the Upper Lahontan Basin, as Double H (47%) becomes the dominant source, followed by Paradise Valley (30%) and Craine Creek (16%), with only minor contributions from Massacre Lake/Guano Valley (7%). Source diversity decreases when farther to the east, as Paradise Valley (66%), Browns Bench (31%), and Double H (3%) are the only primary obsidians represented in Upper Humboldt Plains, while Browns Bench (100%) is the only one found in Thousand Springs Valley.

Although the minor obsidian sources make up only 15% of the total sample, they include about 50 geochemical groups (table 66). Over half of these are represented by fewer than 10 items, and only five sources individually comprise more than 2% of the overall sample. Most of these minor sources (N = 25) occur at sites in the High Rock Country. Twelve of these are also found in the Upper Lahontan Basin, along with the three additional new sources. The frequency of minor sources drops to 11 in the Upper Humboldt Plains, including five from the western regions and seven found for the first time at the project sites. Finally, nine sources are represented in Thousand Springs Valley, six from the west and three appearing for the first time.

Intensity of Production of the Eight Primary Obsidian Sources

Changes in the intensity of obsidian production and use can be measured by tracking the frequency of hydration readings over time. Beginning in the west, the Massacre Lake/Guano Valley obsidian hydration readings (N = 2173) start in the Paleoindian Period and steadily increase over time (fig. 36A). They reach peak frequency in the Middle Archaic Period and drop thereafter, reaching a low in the Terminal Prehistoric Period. When these numbers are time averaged to correct for the differential length of the individual time periods, however, the Middle Archaic increase (281 readings per 1000 years) continues into the Late Archaic Period (334 readings per 1000 years), but still drops in the Terminal Prehistoric Period (only 138 readings per 1000 years).

Craine Creek obsidian produces a similar profile, but its peak is largely restricted to the Middle Archaic Period (fig. 36B). This is true for both the absolute counts and the time-averaged data. The decline from the Middle Archaic (188/1000 years) to the Late Archaic (166/1000 years) is rather slow, the numbers show a precipitous drop at the Terminal Prehistoric Period (12/1000 years).

Fig. 36. Composite obsidian hydration profiles for (A) Massacre Lake/Guano Valley and (B) Craine Creek obsidians.

The other three major western obsidian sources include Mosquito Lake, Bidwell Mountain, and Nut Mountain. For the most part, Nut Mountain obsidian does not produce visible hydration rims, so it cannot contribute to this analysis. Reasonable samples are available for Mosquito Lake (N = 435) and Bidwell Mountain (N = 380), and both source groups appear to produce much flatter, less dynamic profiles than Massacre Lake/Guano Valley and Craine Creek (fig. 37).

Fig. 37. Composite obsidian hydration profiles for (A) Mosquito Lake and (B) Bidwell Mountain obsidians.

When we average by time, however, they show patterns comparable to the larger obsidian samples. Mosquito Lake obsidian hydration frequencies stay rather low and flat through the Paleoindian and Paleoarchaic periods, increase during the Post-Mazama and Early Archaic periods, and again during the Middle and Late Archaic, and drop thereafter. Bidwell Mountain is similar, except that the Paleoindian and Paleoarchaic periods have slightly higher representation than for the other sources.

Moving east to the Upper Lahontan Basin, the Double H obsidian hydration profile is quite similar to that for Mosquito Lake, staying rather low and flat through the Paleoindian and Paleoarchaic periods, increasing somewhat during the Post-Mazama and Early Archaic periods, reaching a peak in the Middle and Late Archaic, and dropping again thereafter (fig. 38).

Fig. 38. Composite obsidian hydration profiles for (A) Double H and (B) Paradise Valley obsidians.

Farther east, however, the patterns begin to change, perhaps due to the increased presence of late prehistoric peoples in these areas. Beginning with Paradise Valley obsidian, hydration frequencies increase through time, but the Late Archaic Period produces much higher time-averaged values (153/1000 years) than the Middle Archaic (81/1000 years), and the Terminal Prehistoric decline seen in the other profiles is now quite muted (104/1000 years). The most extreme version of this change is illustrated by Browns Bench obsidian (fig. 39), which occurs at sites in the Upper Humboldt Plains and is the only primary obsidian source in Thousand Springs Valley (closest to the source). It shows a rather slow unilinear increase over time, with a Terminal Prehistoric time-averaged value of 108/1000 years, much higher than for any other time period.

Fig. 39. Composite obsidian hydration profiles for Browns Bench obsidian.

Discussion

With the exception of Paradise Valley and Browns Bench, which are the two easternmost obsidian sources along the project corridor, the production profiles for the major obsidian sources found at the project site are somewhat similar to those observed for other obsidian quarries along the Sierra-Cascade Front (Hall, 1983; Gilreath and Hildebrandt, 1997, 2011; Ramos, 2000; Hildebrandt and McGuire, 2002; McGuire, 2002; King et al., 2011), but also differ in a variety of ways. First, the size of the Middle and Late Archaic peaks in the current study area are smaller than those exhibited in most of these other areas. For example, the time-averaged hydration values from the Coso Volcanic Field go up threefold from the Early to the Middle Archaic (Gilreath and Hildebrandt, 1997), while this factor of increase is only 1.3 and 1.8 for Massacre Lake/Guano Valley and Craine Creek, respectively.

Secondly, the relationship between Massacre Lake/Guano Valley and Craine Creek (the only true obsidian quarry complexes physically intersecting the pipeline corridor) and Mosquito Lake and Bidwell Mountain obsidian (represented by a few places where low-density float material enters the corridor) also differs from other outlying areas. Farther west along the Sierran-Cascade Front in northeastern California, McGuire (2002) found that a wide range of obsidian sources were used on a casual-encounter basis until the Middle Archaic Period, when a smaller number of high quality sources became the focus of tool-stone production activity. He attributed this change in strategy to an overall decrease in residential mobility accompanied by targeted, logistically based exploitation of fewer but higher-quality sources (see also Smith, 2010, 2011). This decrease in diversity is not apparent in the current sample, as use of all four of the obsidian sources, both major and minor, followed parallel patterns over time.

Based on the abbreviated Middle and Late Archaic production peaks, and the lack of a specialized focus on a limited number of high-quality obsidian outcrops during these intervals, we conclude that the production of surplus obsidian for exchange was probably not a primary activity in the High Rock Country. This is not too surprising, given the lack of large consumer populations living in adjacent areas (unlike cismontane California), as well as the presence of many obsidian and high-quality CCS sources that adjoining people could have easily accessed themselves. This is clearly illustrated by how quickly the mix of obsidian sources changes along the project transect, and how CCS becomes so important in the Upper Humboldt Plains and Thousand Springs Valley (see figs. 33 and 35).

A final topic involving the obsidian hydration profiles is the apparent decrease in production activity during late prehistoric times among the western sources (and similar to the major quarries along the Sierra-Cascade Front). Attributing this decline to the collapse of large-scale exchange systems during the MCA is obviously not appropriate here, if we are correct that obsidian trade was never a major activity for the occupants of this region. The introduction of bow-and-arrow technology is a more likely cause, as the smaller arrow tips did not require the large-scale bifacing industries of earlier times, reducing the need for raw tool stone. It is important to remember, however, that Paradise Valley obsidian densities decreased only slightly in the Terminal Prehistoric Period, and the Browns Bench sample actually shows an increase, further complicating our reconstruction of these relationships.

Flaked Stone Technology

We now turn our attention to flaked stone technological patterns, with the goal of addressing the possible late prehistoric decline in stoneworking discussed above, and reviewing the variety of reduction strategies that were used across the Holocene. Beginning with an atemporal analysis of biface stages and material types (table 67), we see that their composition is quite similar to the full assemblages described above. Obsidian specimens make up 95% of the High Rock County tools but drop to 75% in the Upper Lahontan Basin, 7% in the Upper Humboldt Plains, and 28% in Thousand Springs Valley. Early-stage obsidian bifaces (i.e., stages 1, 2, and 3) comprise 33% of the High Rock County assemblage (consistent with the high number of quarry areas there), while this frequency drops to 11% in the Upper Lahontan Basin, 15% in Upper Humboldt Plains, and 14% in Thousand Springs Valley, due to the lack of nearby obsidian sources (table 67; fig. 40).

Fig. 40. Relative frequency of early-stage bifaces (stages 1, 2, and 3) by material type.

Biface stages for nonobsidian (largely CCS) specimens follow a reciprocal pattern in the east, as early-stage forms are relatively abundant in Thousand Springs Valley (44%) and Upper Humboldt Plains (44%) where CCS tool stone is more abundant (table 67; fig. 40). Upper Lahontan Valley has only 15% early-stage bifaces, probably reflecting the overall lack of naturally occurring CCS and obsidian tool stone in the region, while they are twice as frequent in the High Rock Country (34%), where a limited number of CCS sources were exploited.

A chronological analysis of bifaces from the entire project corridor shows a variety of interesting patterns (Paleoindian assemblages are excluded from further discussion because there are so few bifaces from this interval). First, the raw frequency of bifaces (and debitage) changes significantly over time: they show a sharp increase from the Post-Mazama to the Early Archaic Period, reach an all-time high during the Middle Archaic Period, and drop precipitously thereafter (table 68; fig. 41A). In fact, there are 10 times as many bifaces and 30 times as many pieces of debitage in Middle Archaic components than in those dating to the Terminal Prehistoric Period. When the raw-frequency data are converted to the number of items per 1000 years (fig. 41B), the peak in bifaces moves to the Late Archaic (as does the debitage). The significant decline in flaked stone production activity during the Terminal Prehistoric Period is still apparent.

Fig. 41. A. Absolute frequency of bifaces and debitage by time period. B. Time-averaged frequency of biface and debitage by time period (items per 1000 years).

Biface size profiles also show some interesting changes over time (table 69). We use thickness as a proxy measure, because it is least affected by fragmentation. Although some small fragments (e.g., margins) lack their full thicknesses, we are willing to live with this problem, as it allows us to use the largest possible sample of specimens for the analysis. As we would expect, obsidian bifaces become thinner as they move down the reduction sequence. This basic progression holds for all time periods, but it is important to note that artifacts from the earlier time periods tend to be thicker than the later ones, across all stages. Stage 5 bifaces are a good example: there is a decrease in size, beginning with the Paleoarchaic (6.7 mm) and progressing forward through time (Post-Mazama, 5.5 mm; Early Archaic, 5.0 mm; Middle Archaic, 5.2 mm; Late Archaic, 2.9 mm; and Terminal Prehistoric, 2.6 mm). The major decrease in size between the Middle and Late Archaic periods appears to represent the shift to the bow and arrow, as the mean thickness of Elko points within the larger projectwide sample is 4.9 mm, while that for Rosegate is only 3.3 mm.

The CCS sample follows the same basic pattern, as these specimens also tend to get thinner over time (table 69). They differ from the obsidian bifaces from the Terminal Prehistoric Period, however, as the Stage 4 and 5 specimens seem too thick to reflect an arrow-point reduction sequence. It may be that some of the CCS specimens were designed to be used a knives or as some other multifunction tool.

We now focus on the relative frequency of biface stages over time. The profile changes little during the Paleoarchaic and Post-Mazama periods, with Stage 5/pressure-only specimens being slightly more abundant (fig. 42). Stage 5 bifaces begin to increase in frequency in the Early Archaic, culminating in a Late Archaic peak (67%) and a modest decrease thereafter (51%). So why would the frequency of Stage 5 bifaces increase in this manner over time? One possibility is that many Stage 5 bifaces are worn-out tools (projectile points and knives) that were discarded and replaced with new ones, a possibility that is supported by the thickness data, and that much of this activity occurred in residential settings when people had the time to refurbish their toolkits.

Fig. 42. Biface stages by time period.

This hypothesis is partially confirmed by changes in the mix of site component types over time (fig. 43). For the Paleoarchaic and Post-Mazama periods (particularly the latter), there is a low percentage of habitation components (both simple and complex) relative to flaked stone components. The percentage of habitation components increases in a unilinear fashion through the Late Archaic Period and drops slightly thereafter, following a pattern quite similar to the Stage 5/pressure-only bifaces.

Fig. 43. Relationship between late-stage bifaces and habitation sites.

Reduction patterns produced by the debitage are largely consistent with those of the bifaces (table 70; fig. 44). In the Paleoarchaic, Post-Mazama, Early Archaic, and Middle Archaic samples, obsidian cobble-core reduction debris is dominant, followed by near-equal amounts of biface thinning and finishing debris. This basic biface reduction sequence changed with the advent of the Late Archaic and Terminal Prehistoric periods, and finishing-debris surpasses biface-thinning flakes in those samples. The CCS debitage trends are similar (table 70; fig. 44), also showing higher frequencies of finishing debris than biface thinning during the Late Archaic and Terminal Prehistoric periods. The increased abundance of finishing debris late in time, like the bifaces, seems to correlate with the discard and replacement of worn-out tools at residential sites.

Fig. 44. Debitage types by material and time period.

The Late Archaic and Terminal Prehistoric shift in reduction strategy is also illustrated by tracking the relative percentage of “pressure only” bifaces and biface thinning debris over time (fig. 45). As outlined in chapter 4, pressure-only bifaces are simple flake blanks that did not go through the standard biface reduction trajectory (i.e., they were not thinned) but show pressure-flake removal (finishing). Their relative abundance remained low until the Late Archaic and Terminal Prehistoric periods, when they doubled in frequency, at the same time that the percentage of biface-thinning flakes dropped by half. These findings, when combined with the larger debitage sample, indicate that Late Archaic and Terminal Prehistoric people were not always tied to the full biface reduction strategy.

Fig. 45. Biface thinning debris versus pressure-only bifaces.

Summary and Conclusions

The foregoing discussion demonstrates that obsidian tool stone was quite abundant along the western end of the project corridor but decreased in availability as we head east out of the High Rock Country. All forms of tool stone appear to have been relatively rare in the Upper Lahontan Basin, but the abundance of high quality CCS material increases significantly in the Upper Humboldt Plains and Thousand Springs Valley regions. Reconstruction of flaked stone production patterns was much easier for obsidian than for CCS, as we were able to identify the locations of key obsidian quarry areas through X-ray fluorescence analysis and generate age estimates through obsidian hydration dating. Despite these differences in analytical resolution, our focus on both CCS and obsidian materials from single-component areas allowed us to learn a great deal about the changes in settlement and flaked stone reduction strategies that took place over time.

During the Paleoindian Period, for which we have only small samples, people probably used multiple obsidian quarry areas on a casual-encounter basis as they moved through the area. This generalized approach appears to have continued during the Paleoarchaic and Post-Mazama periods, with much of the record composed of scatters of flaked stone with a high proportion of early-stage reduction debris. With the exception of a handful of habitation areas, it appears that most people did not stay very long within the project corridor, content to obtain flaked stone material in relatively rough form and move on to other locations before modifying it further.

Beginning in the Early Archaic Period, and extending into Middle and Late Archaic, populations increased within the region, and people began to intensify their production of flaked stone tools, particularly using Massacre Lake/Guano Valley and Craine Creek obsidians. We suspect that this also occurred at the Tosawihi chert quarries, but it is difficult to confirm due to our inability to directly date CCS material. Because there was a higher degree of residential settlement in the area at this time, it is possible that specialized visits to the quarries took place more often than had been the case earlier in time.

The Middle and Late Archaic peak in obsidian production has been observed elsewhere along the Sierran-Cascade Front and is often attributed to the production of surplus bifacial blanks for exchange. This does not seem to be the case in the current project, where the peak is less dramatic. There are multiple obsidian sources located to the west and east of the primary quarries in the High Rock Country, so it appears that there was not much of a market for the primary obsidian sources like Massacre Lake/Guano Valley in these areas, as they did not travel very far. If some of the Massacre Lake/Guano Valley obsidian was produced for exchange, it should be found in more southerly locations and in abundances much greater than the lesser sources like Mosquito Lake and Bidwell Mountain, which never experienced the same level of production. Additional research is necessary to determine whether this was the case.

As flaked stone production continued to intensify into the Late Archaic Period, greater emphasis was placed on the use of CCS material as the overall population of northern Nevada increased and people started flowing into the less productive eastern portions of the corridor. The Late Archaic and Terminal Prehistoric periods also saw a change in flaked stone reduction strategies. Rather than always implementing the full biface reduction sequence that had been followed for thousands of years, many people took flake blanks and pressure flaked them into finished implements, entirely bypassing the biface-thinning phase of production.

Finally, irrespective of the flaked stone technology, there was a truly remarkable overall decrease in flaked stone activity during the Terminal Prehistoric Period. As outlined above (see fig. 41), the number of items deposited per unit time is almost identical to that found during the Early Archaic Period (more than 4000 years earlier), when most researchers think population densities were much lower. There was also a fourfold decrease in the intensity of flaked stoneworking compared to the preceding Late Archaic Period. Although some might argue that this could reflect major decreases in population, this seems highly unlikely based on our component and radiocarbon data (see chap. 10), as well as previous studies seeking to explain the expansion of Numic-speaking people into northern Nevada and elsewhere (Bettinger and Baumhoff, 1982).

Of the alternative proposals used to explain this abrupt change in technology, the current data favor the idea that the introduction of the bow and arrow required less tool stone overall and reduced the need for the full biface reduction strategy. While we have provided some evidence for this scenario, it also seems that something more significant and more elusive must have taken place. Take, for instance, the large Terminal Prehistoric antelope drives investigated along the eastern end of the corridor (see chap. 16). Although these features include structural remains built to obtain large game, most of them lack well-developed flaked stone assemblages (also see Jensen, 2007). Conversely, high concentrations of Early and Middle Archaic projectile points found in the same habitats (but lacking the perishable fences) are thought to signal the same kind of activity—antelope drives (Hockett and Murphy, 2009).

This distinction has led Jensen (2007) to conclude that the earlier artifact concentrations do not mark actual corrals, but surrounds created by numerous male hunters armed with atlatls and darts. The Numic corrals, in contrast, were built by all members of the group, and the animals, once tired from being pursued in the corral, could be dispatched rather easily without sophisticated weapons. If this is true, it could indicate that Numic peoples invested greater amounts of up-front labor in the production of hunting facilities than did their predecessors. By putting a greater emphasis on corrals, large nets, deadfalls, and traps, their need for formalized flaked stone tools may have been reduced. It is also important to note that the nature of tool-stone quarries changed over time, especially for people willing to use more limited amounts of stone. Whereas the first people entering an area needed to find the primary sources of tool stone, 10,000 years of occupation created thousands of flaked stone scatters across much of the landscape—scatters that could have been harvested by Numic peoples when the need arose.

CHAPTER 12: TRANS-HOLOCENE SUBSISTENCE-SETTLEMENT CHANGE IN NORTHERN NEVADA

Kelly McGuire, Andrew Ugan, Kimberley Carpenter, and Laura Brink

Elsewhere in this presentation we have focused on the human colonization of northern Nevada and population reconstructions using a variety of archaeological proxy measures (chap. 10). We have also more narrowly addressed issues of assemblage structure, subsistence, and settlement in summaries developed for each of the four project regions, and again with regard to the evolution of geophyte procurement in the High Rock Country (chaps. 6–9 and 13). In this chapter, we assess subsistence-settlement change along the entire project corridor, with a focus on interregional trends.

We start with the trans-Holocene population profile for northern Nevada developed in chapter 10, as some portion of the assemblage variation through time is explained by population growth. Population growth among hunter-gatherers, along with effective environment and available technology, informs various foraging decisions through time. To track these decisions, we rely not only on direct subsistence data, such as faunal and archaeobotanical remains, but also on the frequency and distribution of major artifact classes that are reflective of plant procurement on the one hand (e.g., milling stones and hand stones), and hunting and hunting-related activities on the other (e.g., projectile points and bifaces). These artifact classes also have clear gender attributions, and their representation in certain contexts has broad implications for work organization, demography, and land use. We conclude this chapter with a period-based discussion of the archaeological record from the Ruby Pipeline project and how it is situated with regard to various hypotheses of prehistoric culture change in the Great Basin. These include shifts in subsistence settlement, changes in residential patterns and mobility, and broad trends in tool-stone production and hunting practices.

Population Change

Although several proxies of projectwide population density through time are presented in chapter 10, the frequency of single components standardized per 1000 acres and 1000 years is arguably the most comprehensive. This frequency is graphed in figure 46 and arrayed by region on table 58 in chapter 10 (page 228).

Fig. 46. Frequency of single-component areas per 1000 years and 1000 acres of land.

As can be seen, population density remains comparative low from the Paleoindian through the Post-Mazama periods. It nearly quadruples during the Early Archaic Period and continues advancing through the Middle and Late Archaic periods before declining somewhat during the Terminal Prehistoric Period.

Settlement Change

Elsewhere (see chaps. 6–9), we have defined a series of site component types that characterize the structural complexity of the assemblages and features associated with dated project components. These are considered rough settlement types and include the following categories: flaked stone, quarry, simple habitation, complex habitation, flaked stone with feature, and feature only. The simple and complex habitation sites are distinguished by the presence of milling equipment and thus indicate a broader range of subsistence activities and component occupation by a more inclusive demographic group that included women. Those settlement types that include features—virtually all are rock and charcoal-stained processing features—are also suggestive of subsistence activities carried out by women. By contrast, both the flaked stone and quarry categories are limited to hunting weaponry and hunting-related tool manufacturing debris typically associated with males.

Against the backdrop of changes in population density enumerated above, we attempt to measure shifts in settlement configuration through time. We are particularly interested in the ratio through time of the habitation components (simple, complex, flaked stone with feature, and feature only) to those components that are represented solely by flaked stone (both simple and complex). While we admit that milling equipment is a poor behavioral indicator for the Paleoindian Period (because it wasn’t used), and to some degree during the Paleoarchaic Period for the same reasons, we still feel that it provides the broadest measure of habitation and residential behavior when considering trans-Holocene trends across the Northern Tier.

This ratio is graphed by time period in figure 47, and as can be seen, closely resembles the trend line for population growth (see fig. 46). As might be expected, earlier time periods—Paleoindian, Paleoarchaic, Post-Mazama—are characterized by comparatively low frequencies of habitation components. Commencing in the Early Archaic Period, the percentage of habitation components begins to increase, and it rises through each subsequent period. At this gross level we can conclude that, prior to about 5000 or 6000 years ago, the Northern Tier was probably the locus of more transitory logistical hunting forays and tool-stone resupply activities that resulted mostly in flaked stone scatters. The earliest occupations along the project corridor, documented in the Parman Basin, potentially predate the widespread use of milling implements, but they represent only a very small percentage of the total project component inventory. After about 5000 years ago, we see a more robust trend for greater habitation activity, with residential sites that were occupied by more extended social groups that included both men and women.

Fig. 47. Ratio of habitation components to nonhabitation components through time.

It seems likely that at the close of the middle Holocene warm/dry period, favorable environmental conditions provided opportunities for more stable residential use of the study area, which in turn allowed for greater population densities. This concordance between rising population density and the frequency of habitation components breaks down only in the Terminal Prehistoric Period. At this time, population proxies show a decline, whereas the relative frequency of habitation sites continues to rise.

We suspect that this signals a basic shift in land use resulting from the arrival of the Numa along the Northern Tier sometime after 600 cal b.p. Their family band structure would have been weighted toward a series of small residential settlements dispersed across the landscape, although (the data suggest) at lower overall population densities.

Changes in Assemblage Structure

Having established the broad outline of trans-Holocene population growth and major shifts in settlement structure, it remains to explore the underlying changes in assemblage structure and lifeways that are linked to these macrotrends. We first review major artifact profiles by time period and then follow with an assessment of dietary constituents, including faunal and archaeobotanical remains.

With respect to the primary classes of artifacts, the frequency by component of both bifaces and milling equipment provides an important gauge of subsistence orientation. The former, including all reduction stages, provides an overall measure of flaked stone tool production, most of which is focused on hunting-related implements. The latter provides a direct measure of the intensity of plant processing generally assumed to be domain of women. The density by component of each of these tool classes is arrayed in table 71.

What is noteworthy in the trends for both artifact classes is that they diverge somewhat from the population curve and settlement profile (see fig. 46; fig. 47), especially at the latter end of the sequence. Middle Archaic components contain the highest densities of both bifaces and milling equipment. This suggests more intensive occupation of settlements by larger demographic groups that tended to include both men and women—a higher degree of residential stability. This residential pattern during the Middle Archaic Period has been recognized elsewhere in the Great Basin (McGuire and Hildebrandt, 2005), and it may have provided important central places from which logistical hunting forays were based, thus explaining why hunting-related tools are found in abundance.

Population densities are modestly higher during the Late Archaic, and the ratio of habitation to nonhabitation components continues to rise, while the density of milling equipment in these components shows a marked drop. We suspect that while the Middle Archaic residential pattern may have continued well into the Late Archaic Period, populations may have been more widely dispersed at this time and somewhat less likely to concentrate in central residential bases. As we review below, some researchers have also suggested that a regional Late Archaic increase in foraging efficiency and technological investment led to greater reliance on hunting, with less effort directed at the processing of plant foods (Cannon, 2010; Broughton et al., 2011).

Given the settlement profile illustrated in figure 47, it is not surprising that the Terminal Prehistoric is also characterized by high densities of milling equipment, albeit somewhat lower than the Middle Archaic Period. There is, however, a substantial falloff in biface density during the Terminal Prehistoric Period, almost by a factor of three. Projectile point frequencies (see chap. 10) and a number of other measures of tool-stone production (chap. 11) also decline.

This reduction in tool-stone production and the frequency of hunting-related flaked stone artifacts may not necessarily reflect an overall reduction in the hunting of large game. Alternative explanations include lower demand for tool stone resulting from the introduction of the bow and arrow; greater use of hunting facilities, such as corrals, larger nets, deadfalls, and traps; and scavenging of previously reduced tool stone from older archaeological sites.

Up to this point, we have addressed subsistence change indirectly through the use of general broad artifact classes, such as milling equipment (plant procurement) and bifaces (hunting-related activities). Next, we focus on the dietary remains recovered from across the project transect. The most important of these are the archaeobotanical remains recovered from 203 project samples. As they were recovered from flotation samples that also yielded abundant wood charcoal, most have associated radiocarbon dates that allow for more precise temporal period assignment. The project inventory of faunal remains is much more uneven and is characterized by only a small number of spatially and temporally disparate sites that have viable assemblages. We have addressed this issue by expanding the database to include a number of previously reported faunal assemblages from elsewhere in the northern Great Basin.

Archaeobotanical Remains

A total of 3709 small seeds and 33 nutshell fragments was recovered from the 203 flotation samples analyzed. Of these, 32 small-seed and two nutshell genera are recognized; these results are reported in the regional summary discussions in chapters 6–9.

Our approach here focuses on projectwide diet breadth through time as measured by plant diversity and richness for each time period. The former is computed by use of the Simpson’s diversity index, and the latter is represented by the total number of genera identified by time period. As diversity statistics are key to this discussion, a Pearson’s r value correlation was calculated for the Simpson index, and the number of seeds present in each temporal component was adjusted by sampling fraction (Grayson, 1984). This relationship yielded a Pearson’s r value calculated at 0.198, affirming that seed diversity is explained by factors other than sample size.

Both the diversity and richness data are provided in table 72 and plotted for the entire project area in figures 48 and 49. Most seed remains were recovered from components dating to the Early, Middle, and Late Archaic and Terminal Prehistoric periods. The indices show broadly similar trend lines with marked expansion of plant diet breadth from the Early Archaic into the Middle Archaic. There is a falloff during the Late Archaic Period, followed by new increases in the Terminal Prehistoric Period where they reach their highest levels.

Fig. 48. Simpson diversity index for all project archaeobotanical remains by time period.

Fig. 49. Taxa richness for all project archaeobotanical remains by time period.

What is most noteworthy about these indices is the degree to which they correspond to the density of milling equipment for each temporal component detailed in table 71. Thus, for example, the increase in plant diet breadth between the Early and Middle Archaic periods is mirrored in an increase in milling tool density, and the falloff in diet breadth during the Late Archaic Period is reflected by a decrease in milling tool density. The highest levels of plant diet breadth are documented in the Terminal Prehistoric Period, which is also represented by high densities of milling equipment (although, as we have indicated earlier, at a slightly lower level than observed for the Middle Archaic Period).

One additional aspect of plant resource intensification includes geophytes, which are not typically well represented in flotation samples. This subject is treated in detail in chapter 13, with a geographic focus on the High Rock Country and in particular, epos (yampah) exploitation in the Barrel Springs uplands. Noteworthy is the conclusion that this type of procurement system may have begun during the Early Archaic Period and reached its highest expression during the Middle Archaic Period. In this sense, it appears to be part and parcel of the Middle Archaic elaboration in plant resource exploitation noted in the milling assemblage and archaeobotanical data reviewed above. This same expansion in geophyte use may have occurred along the entire project corridor, although there are no definitive data to confirm this.

Faunal Remains

A total of 15,669 pieces of animal bone was recovered from 97 different sites in the project corridor. Of these, 13,655 were assigned to a specific temporal component and 11,573 were assigned to both a time frame and (at least) a broad size class (table 73). The latter group includes 48 temporal components from 40 different sites. Detailed results are presented in each of the regional summaries (chaps. 6–9). As previously mentioned, there are two reasons that some caution should be taken in treating these faunal remains as a metasample for subsistence and land-use reconstructions similar to those applied to the archaeobotanical data. First, the vast majority of specimens are assignable only to broad size class—much of the assemblage is identified only as mammalian, primarily small-medium, medium-large, and large mammals. Only a smattering of birds, fish, reptiles, and amphibians were documented. Second, the sample is uneven with regard to both size and geography—54 of 97 sites yielding faunal remains have 10 or fewer identifiable bone specimens, and the five largest sites (all spatially disparate) contain 75% of all fauna.

Notwithstanding these limitations, size-classified fauna are relatively abundant and permit an examination of changing reliance on big game through time. This is done by computing an abundance index (AI) based on the ratio of large-bodied animals to the sum of large and small ones. Given a generally close correspondence between a prey’s body size and its energetic return rate (Bayham, 1979; Broughton, 1994, and references therein), declines in large-bodied animals relative to small ones imply declining foraging returns, although it can be difficult to know whether declining availability of large-game animals resulted from overhunting or nonhuman activities (e.g., environmental shifts and changes in habitat productivity).

There has also been an acknowledgment of potential difficulties in the use and interpretations of these indices. These include possible violations of the assumption that small-bodied organisms provide lower return rates than larger ones (Bettinger, 1993; Madsen and Schmitt, 1998; Grayson and Cannon, 1999); discussions of “mass collecting’’ and the value of large numbers of small resources (Steele and Baker, 1993; Madsen and Schmitt, 1998; Ugan, 2005); questions concerning prey mobility and hunter success rate as they affect the value of large versus small game (Bird et al., 2009; Broughton et al., 2011; Ugan and Simms, 2012; Jones et al., 2013); and issues of nonenergetic foraging goals and the social context of foraging (Hildebrandt and McGuire, 2002; Hockett, 2005; McGuire and Hildebrandt, 2005; Bird et al., 2013). Whether dealing with changing energetic returns or some other interpretation, however, all approaches rely on the same type of index.

With that in mind, we examine changes in the relative AI of small and large animals through time and space. The individual component is the basic unit of analysis, with trends graphed as the mean AI value of all components falling in the same period. Individual components are equally weighted regardless of sample size (number of individual specimens present [NISP]), although we also explore the effects of excluding smaller components.

In order to place the Ruby fauna in a broader context, we have also collated previously published faunal data from nearly two dozen other projects conducted throughout the northern Great Basin and very southern Columbia Plateau (Shutler and Shutler, 1963; Heizer et al., 1968; Aikens, 1970; Cowan, 1972; Dalley, 1977; Grayson, 1979a, 1979b, 1988; Kobori, 1979; Bard et al., 1980; Follett, 1980; Dansie, 1987; Elston and Budy, 1990; Schmitt and Sharp, 1990; Greenspan, 1993; Dean, 1994; Delacorte et al., 1997; Kelly, 2001, 2007; Young, 2002b; McGuire et al., 2004; Cannon, 2012). These represent 142,375 specimens from 88 additional sites, each of which could be assigned to size class and temporal component. The chronological framework used at these sites typically differed from that used on the Ruby Pipeline, often crosscutting temporal components. For example, a particular stratum may date between 3000 and 1000 b.p., which would straddle the Middle and Late Archaic as defined here. In these cases, deposition was assumed to occur uniformly across the entire time span, and fauna were assigned proportionately to each temporal component. After standardizing the timescales, relevant abundances were calculated based on the proportion of large and small fauna falling into each component, as described earlier.

Figure 50 plots AI values across time for (1) all Ruby component assemblages; and (2) all non-Ruby component assemblages. As can be seen, large game are generally rare in the early components of Ruby sites, but increase quickly from 6% of the assemblage in the Paleoarchaic Period to almost 36% of the assemblage by the Post-Mazama. They then rise to a high of 63% during the Early Archaic before dropping to between 42% and 53% of the assemblage thereafter. Of note is a slight uptick in the AI associated with the Terminal Prehistoric Period. The overall pattern for the non-Ruby fauna is roughly similar—increasing AIs as a function of time—but without the dramatic increases observed in the Ruby fauna for the Early and Middle Archaic periods. It is also noteworthy that the highest AI in the non-Ruby sample was documented during the Terminal Prehistoric Period.

Fig. 50. Artiodactyl abundance indices for ruby and non-Ruby faunal assemblages.

When Ruby and non-Ruby fauna are considered together, the dataset suggests a major transition in large-game hunting beginning in the Early Archaic Period. Prior to this time, AI values are comparatively low, whereas later in time they are generally higher. The Ruby data in particular point to a peak in large-game procurement during the Early and Middle Archaic. Similar patterns have been identified elsewhere, both at individual sites (McGuire et al., 2007) and across larger catchments such as the western Great Basin and western Wyoming Basin (Delacorte et al., 1997; McGuire, 2004; Byers et al., 2005). Somewhat unexpected is the importance of large game at the latest end of the prehistoric sequence, during the Terminal Prehistoric Period (see the Discussion section immediately below).

Finally, it is worth noting the substantial variability underlying both trend lines in figure 50. In any given time period, individual components exhibit a wide array of AI values (fig. 51). This variation almost certainly reflects the underlying reality of human foraging where a wide range of habitats and species were hunted throughout the seasonal subsistence round, and were processed and consumed in a variety of settlement contexts. Still, the trends exhibited in these metadata track the shifting reliance on particular classes of fauna and potentially provide insight into important environmental, settlement, technological, and social trends.

Fig. 51. Individual component variation and mean component values in artiodactyl abundance indices for both Ruby and non-Ruby sites.

Discussion

It should be reiterated at the outset that the Northern Tier was and still remains a relatively resource-poor region of the Great Basin, lacking keystone crops such as pinyon and generally bereft of the marshes and lake basins that sustained populations elsewhere. Through much of the Holocene, it remained comparatively underutilized, being mostly the domain of the occasional long-range logistical hunter and a supply area for tool stone. As we have demonstrated, however, land use was not static. Indeed, it may be that subtle changes in subsistence and settlement exhibit greater archaeological visibility along our transect because most sites were not subjected to repeated occupations and the resulting overprinting and mixing of assemblages. We see this in the large number of low-density, single-component contexts identified in the study area. It also helps that our project sample is both methodologically uniform and spatially extensive and thus, arguably representative along its entire 360 mile length. Presented below is a discussion of subsistence and settlement practices for each time period.

Paleoindian and Paleoarchaic

With regard to the earliest occupations documented along the study corridor, including those attributed to both the Paleoindian and Paleoarchaic periods, there is ample evidence that these initial colonizers targeted the comparatively resource-rich High Rock Country (chap. 10). As might be expected, reconstructed population densities are the lowest of any period (see fig. 46) and components are typically flaked stone scatters bereft of any milling equipment. Bifaces show a tendency toward early-stage forms, and debitage profiles are consistent with a standard biface-reduction sequence (chap. 10).

The only evidence of longer-term habitation during this time frame was documented at 26HU4943 and 26HU5105, located along the shoreline of pluvial Lake Parman. A living surface, perhaps a house floor, was documented at the latter site, and both sites produced radiocarbon dates of 11,180 cal b.p. Artifacts from these locations, as well as several others in this same lakeshore context, include stemmed-series projectile points, bifaces, unifaces, and other formed flaked tools typical of assemblages across the Great Basin dating to this time.

There is little direct dietary evidence in the form of either faunal or archaeobotanical materials from the earliest project components, although the assemblages, with their emphasis on flaked stone tools, certainly suggest some attention to hunting-related activities. As we review in chapters 10 and 13, we also suspect that geophyte productivity, particular for epos, was of critical importance and also sustained these early colonizers in the High Rock Country. As detailed in chapter 13, the procurement, processing, and consumption of epos does not, in the absence of storage, require milling tools. It does, however, involve an assemblage of simple and formed flake tools for the manufacture and maintenance of digging sticks to harvest these geophytes.

The obsidian source profiles for this time frame (chap. 14) generally confirm a previously recognized pattern of geographically extensive residential mobility (Kelly and Todd, 1988; Amick, 1996; McGuire, 2002; Jones et al., 2003, 2012; Smith, 2010, 2011; Beck and Jones, 2011). Note, however, as reflected on table 82 in chapter 14 (page 309), that while the procurement premium for projectile points (measured as average kilometer distance beyond the first available source) is higher than in the Early, Middle, and Late Archaic periods, it is not as high as in the Terminal Prehistoric Period.

Post-Mazama

As this period includes the most intense era of middle Holocene warming (chap. 2), it is not surprising that the archaeological visibility of components dating to this time remains very low, with population densities little changed from the previous Paleoarchaic Period (see fig. 46). Although other researchers have postulated a more definitive population decline at this time (Grayson, 2011: 304–307), there is no evidence for the wholesale abandonment of the Northern Tier, though most components dating to this time are concentrated in the relatively well-watered and more productive High Rock Country (chap. 10). We do not view this as a “retreat” to so-called well-watered refugia (Grayson, 1993, 2011; Beck, 1995; McGuire, 2007: 170–172; Milliken and Hildebrandt, 1997), however, because previous Paleoindian and early Holocene Archaic populations were not well established in the central and eastern regions of the project corridor to begin with.

Simple and complex habitation components, defined primarily by the presence of milling equipment, are represented at the same low frequency as Paleoarchaic components, despite the widespread use of milling gear elsewhere by this time (see fig. 47 and table 71). This is not the Post-Mazama residential pattern observed at Menlo Phase components in Surprise Valley (O’Connell, 1971, 1975), nor does it bear much resemblance to Chatters’ (2012) conception of “opportunistic sedentism” for foragers dating to this time. Indeed, most Post-Mazama project components are scatters of flakes and the odd projectile point or biface—more indicative of the occasional long-range hunting foray into this region rather than any sustained habitation. This level of mobility, presumably resulting from logistical hunting activities, is confirmed by the relatively high transport distances for obsidian projectile points that is slightly less than the Paleoarchaic value but still higher than those values for the ensuing Early, Middle, and Late Archaic periods (see table 82, page 309).

Early and Middle Archaic

The Early and Middle Archaic time frame marks the initiation and subsequent acceleration of sustained habitation along the Northern Tier. The simplest measures of this are an abrupt rise in population density (see fig. 46) coupled with an increase in habitation components (see fig. 47). These trends are accompanied by the increasing occupation of more marginal resource tracks located in the eastern regions of the project area (chap. 10), no doubt driven by the transition to more favorable late Holocene climatic conditions. While climate may have begun to improve slightly as early as 6300 cal b.p., it was not until about 4500 cal b.p.—well into the Early Archaic—that this transition was more or less complete (chap. 2).

Densities of major artifact categories, including milling tools and bifaces, peak during the Middle Archaic Period (see table 71). Archaeobotanical diversity indices (see figs. 48 and 49) spike in the Middle Archaic Period, suggesting a marked expansion of plant diet breadth from the Early Archaic into the Middle Archaic (McGuire et al., 2004; Wohlgemuth, 2004). Related to this, there appears to have been an expansion of geophyte procurement in the High Rock Country that may also have been expressed in other areas (chap. 13). This all appears to have been accompanied by an increased reliance on the taking of large game (see fig. 50).

We are inclined to tie these transformations to similar changes observed throughout the Great Basin and parts of California. As noted in chapter 3, this is the time that true settlement hierarchies emerge, along with the first substantiated occupation of large semisedentary base camps (Zeanah, 2004). Such large, semisedentary residential complexes have been documented along the Humboldt Lakebed (Livingston, 1986), Carson Sink (Raven and Elston, 1988; Raymond and Parks, 1990; Kelly, 2001; Madsen, 2002), Humboldt River near Battle Mountain (McGuire and King, 2011), the Lake Albert–Chewacan marsh basin (Oetting, 1990; see also Jenkins et al., 2000), and the northwestern Great Basin (Elston et al., 1994; see also Riddell, 1960; McGuire, 1997). Similar manifestations have been reported in northeastern Nevada (McGuire et al., 2004) and the eastern Great Basin (Madsen and Simms, 1998). We have previously argued that the Middle Archaic Period may actually represent the “trans-Holocene highpoint” of residential stability in most areas of the Great Basin (Hildebrandt and McGuire, 2002; McGuire and Hildebrandt, 2005).

Increasing levels of habitation within the project corridor contributed to major shifts in flaked stone procurement and production. At some key obsidian source areas, notably Massacre Lake/Guano Valley and Craine Creek, there was a shift from casual, low-intensity use to a more targeted and sustained procurement, with production peaking in the Middle Archaic Period (chap. 11). The emphasis was on biface production and, as previously indicated, in both an absolute sense and when measured as average component density, biface production reached its highest level during the Middle Archaic.

Interestingly, projectwide obsidian source diversity reached its lowest Holocene levels at this time, as indicated in the transport distances for projectile points (see table 82, page 309). As a measure of overall mobility, this trend is the result of the increased residential stability described above. In this scenario, rather than a more geographically expansive pursuit of tool stone that might be expected in a residentially mobile population, effort was directed more intensively at a fewer number of key source locations. This same pattern of decreasing mobility during the Middle Archaic Period has been observed with large-scale data sets from elsewhere in the northwestern Great Basin (McGuire, 2002, 2007; Smith, 2010).

Given the density of bifaces in Middle Archaic components, as well as the relative abundance of projectile points dating to both the Middle and Late Archaic periods (see chap. 10), it is hard not to conclude that hunting as measured by hunting-related tool production was in ascendance at this time; this appears to be confirmed in the faunal profiles from the Northern Tier (see fig. 50).

In sum, and as promulgated by several researchers (Hildebrandt and McGuire, 2002; Zeanah, 2004; McGuire and Hildebrandt, 2005), a land-use framework featuring relatively high levels of residential stability and increased diet breadth related to plant resources and women’s work organization was operable during this time along the Northern Tier. This appears to have been coupled with, and perhaps allowed for, relatively high levels of logistical mobility associated with long-range logistical hunting undertaken by men.

Late Archaic

Reconstructing land use during this period is particularly challenging, as it was time of profound cultural change possibly induced by severe drought associated with the Medieval Climatic Anomaly (MCA), changes in technology, and perhaps social conflict, or some combination of these. As we have previously reviewed (chap. 3), most of these changes are thought to have occurred in the latter half of this period, after approximately 1000 cal b.p., thus potentially splitting the Late Archaic into an earlier phase, where conditions may have been more like the preceding Middle Archaic Period, and a later-dating phase marked by environmental and social disruptions.

Against this backdrop, we compute that population density along the Northern Tier probably peaked at this time, as have a number of other researchers using the ubiquitous Rose Spring and Eastgate point forms as population proxies (Thomas, 1971, 1988; Livingston, 1986; Elston and Budy, 1990; Delacorte et al., 1992; Elston and Raven, 1992: 613; Elston and Bullock, 1994; Hildebrandt and King, 2002, 2012; Delacorte, 2008; Cannon, 2010: 83; McGuire and King, 2011). However, if we narrow our focus to radiocarbon dates as a population proxy (see chap. 10), we see that most project radiocarbon dates associated with the Late Archaic Period—13 of 17 dates—fall before 1000 b.p. Although not definitive, this correlation would suggest that population growth was more robust during the first half of the Late Archaic Period.

With respect to settlement structure, we have also demonstrated the continuing expansion of habitation components as a ratio of all other settlement types during this time (see fig. 47). Surprisingly, however, this increase in habitation is accompanied by a sharp decline in the component density of milling equipment. We suspect that while the Middle Archaic residential pattern may have continued well into the Late Archaic Period, populations may have been more widely dispersed at this time and somewhat less likely to concentrate in central residential bases.

More intriguing is the fact that this falloff in the density of milling equipment is accompanied by a noticeable decline in diet breath related to small-seed and nut procurement (see figs. 48 and 49). A similar pattern was observed at Little Boulder Basin, located immediately south of the project corridor in the Upper Humboldt Plains region (Cannon, 2010; Broughton et al., 2011). In comparison to Middle Archaic and Terminal Prehistoric components, Late Archaic components are characterized by high relative frequencies of projectile points, a high artiodactyl AI, low relative frequencies of milling tools, and lower aggregate archaeobotanical richness from radiocarbon-dated features. This overall pattern is linked to increases in foraging efficiency associated with the taking of large-bodied prey (Broughton et al., 2011).

By contrast, there are any number of regional studies that identify comparatively lower AI values (Carpenter, 2002; McGuire et al., 2004), as well as a broad trend toward resource intensification, i.e., broadening of the diet breadth, during the Late Archaic Period (Elston, 1986: 145; Leach, 1988; Elston and Budy, 1990; Delacorte, 1997, 2002; McGuire et al., 2004). Similarly, the notion of increased foraging efficiency during the Late Archaic is at odds with the florescence of agriculture (perhaps the ultimate expression of resource intensification) in the Fremont culture zones located immediately to the east.

The data at hand are probably not sufficient to adequately reconcile these two competing perspectives; however, it is clear that Late Archaic land-use patterns were more complex than have been previously acknowledged. We suspect that much of this complexity is rooted in this issue of a pre-1000 cal b.p. versus post-1000 cal b.p. Late Archaic—with the start of the MCA as early as 1100 cal b.p., both climate and land-use patterns abruptly changed, and this distinction is lost when lumping together all assemblages that date from 1300 to 600 cal b.p.

With respect to changes in tool-stone procurement and production, the Late Archaic Period begins to show signs of an emerging Late Prehistoric pattern. The high ratio of obsidian to nonobsidian tool stone in the Middle Archaic begins to reverse, with nonobsidian tool stone (primarily cryptocrystalline silicate, or CCS) becoming dominant in Late Archaic components (chap. 11). The increased use of CCS may have more to do with intensified late occupation in project segments that are rich in CCS, although this trend has also been viewed as reflecting local resource intensification, settlement contraction, and overall territorial circumscription (Basgall and McGuire, 1988; Elston and Budy, 1990; Gilreath and Hildebrandt, 1997; Bettinger, 1999b; Smith, 2010). Obsidian source diversity and transport distances for projectile points, however, begin to increase from their Early and Middle Archaic lows, reaching a zenith in the Terminal Prehistoric Period (see ahead to table 82, page 309). In a subject we will return to below, this may have less to do with mobility and territorial range than it does with Late Prehistoric social networks, including trade and exchange.

Terminal Prehistoric

In consideration of the broad late Holocene population and assemblage trends previously described, the Terminal Prehistoric Period exhibits perhaps the most significant break. It is at this time that our primary proxy for population density—single-component areas per 1000 years—shows its first decrease (see fig. 46). Terminal Prehistoric population decline has been identified in other specific geographic contexts, such as the Middle Humboldt River drainage (McGuire and King, 2011), but its corroboration along the entire study corridor suggests that a wider demographic shift was at play. Causal factors include the arrival of the Numa with their new family-band sociopolitical organization (Steward, 1938), and the lingering effects of the MCA, which may have disrupted subsistence-settlement systems and entire cultures throughout California, the Great Basin, and the Southwest (Jones et al., 1999).

Work and residential activities were much less segregated at Numic settlements, possibly producing a “stand alone” quality that might be expected by a series of dispersed and short-term occupations by small family units. It is not surprising, therefore, that the archaeological manifestations of these small residential occupations—simple and complex habitation components—reach their highest expression relative to all other component types in the Terminal Prehistoric Period (see fig. 47).

Given that these components were occupied by family units composed of both men and women, it is not surprising that the density of milling equipment rises in these contexts relative to Late Archaic levels (see table 71). This same pattern has been noted in a number of other regional contexts near the study corridor, including Secret Valley (McGuire, 1997), Black Rock Desert (Seck, 1980), the Buffalo Hills region (Kolvet, 1995), Duck Lake (Creger, 1991), and Little Boulder Basin (Cannon, 2010). It is notable also that diet breadth associated with plant procurement, as indicated in archaeobotanical diversity indices from the project corridor (see figs. 48 and 49), reaches its highest levels during the Terminal Prehistoric Period. As we review in chapter 15, the introduction of pottery at this time, in the eastern portion of the study corridor is probably a reflection of the importance of small seeds. When considered together, these data point to a subsistence regime characterized by resource intensification.

One of the more interesting trends for this time period is the apparent continued reliance on large game at both the project sites and throughout the northern Great Basin (see fig. 50). This generally does not comport with more traditional conceptions of Numic lifeways, where several local studies point to an increasing reliance on small game and less focus on the taking of artiodactyls during the Terminal Prehistoric Period (Spencer et al., 1987; McGuire et al., 2004; McGuire and Hildebrandt, 2005; Cannon, 2010). However, it is consistent with findings in a variety of other places recently documented by Hockett (2015). Finally, we see a decrease in component densities of projectile points as well as overall flaked stone production (chaps. 10 and 11).

One explanation may relate to the continuance and perhaps increased use of large game drive facilities and traps (Hockett and Murphy, 2009). Several such late-dating drive complexes were documented in the eastern portion of the study area (26EK3959 and 26EK12310) and others are reported from northeastern Nevada (chap. 16). As we mentioned earlier, the greater use of hunting facilities, such as corrals, larger nets, deadfalls, and traps, may have somewhat mitigated the need for weaponry. Such activities, although episodic, may have created resource bonanzas, the remains of which are concentrated in certain habitation sites.

As we describe in chapter 11, obsidian quarry production, particularly for Massacre Lake/Guano Valley and Craine Creek, abruptly declines during the Terminal Prehistoric Period—a pattern also observed at a number of major quarry zones located in the Inyo-Mono region (Coso, Casa Diablo, Bodie Hills, and Modoc Plateau [Medicine Lake Highlands]). As we also note in chapter 11, biface reduction falls off and is replaced to some extent by the use of less formalized tools. This quarry trend suggests a decentralization of tool-stone production away from quarry zones and toward end-point users, in this case a series of widely dispersed family bands.

Finally, one of the more noteworthy results of this study is the very high obsidian transport distance for obsidian projectile points, which reaches its highest level during this time compared to any other period (see chap. 11). This pattern has been observed before with large point assemblages in the northwestern Great Basin and Modoc Plateau, where it is seen less as a reflection of logistical or residential mobility, and more as attributable to factors such as increasing trade and exchange, scavenging and reuse of older archaeological materials, and increasing use of obsidian nodules in a dispersed, secondary context (McGuire, 2002: 85–104; see also Smith, 2010). Even more impressive is the distance that obsidian debitage travels at this time—nearly sixfold that of any other period. The figure is actually higher than that for projectile points dating to this time, indicating that, along with value-added finished tools, more minimally reduced tool stone was also being conveyed over large distances. This represents a major break in tool-stone production and conveyance from previous periods. As we review in chapter 15, this sudden reorganization of obsidian conveyance may reflect the arrival of the horse as a means of transportation in the northern and central Great Basin at the very end of the prehistoric period.