Browsing by Author "Taylor, Beryl E."
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Item A generic review of the stenomyline camels. American Museum novitates ; no. 2353(New York, N.Y. : American Museum of Natural History, 1968) Frick, Childs, 1883-1965.; Taylor, Beryl E.Item A generic revision of the Protolabidini (Mammalia, Camelidae) with a description of two new protolabidines. Bulletin of the AMNH ; v. 161, article 3(New York : American Museum of Natural History, 1978) Honey, James G.; Taylor, Beryl E."A revised diagnosis of the Protolabidini characterizes the tribe as having a narrow rostrum and laterally expanded anterior nares. Tanymykter, new genus, possess the above derived features and is included in the Protolabidini as the primitive sister taxon to Protolabis. The morphological features that separate Tanymykter from Protolabis are all primitive except for the derived condition of closely appressed P[superscript]1[subscript]1 roots. Based upon new material from the Milk Creek Formation, morphological distinctions between Protolabis and Procamelus are clarified. The principal derived features of Protolabis coartatus that differ from Procamelus are extreme constriction of the rostrum, lateral expansion of the anterior nares, P[subscript]1 and P[subscript]2 small and sometimes absent, and a mandibular angle with extreme lateral flare and a prominent mesial tuberosity. Although the above derived features are less pronounced, they are still present in Protolabis heterodontus and other undescribed samples in the collection of the American Museum of Natural History. Thus, Stirton's species, coartatus, which has previously confused the generic concept of Procamelus, is transferred to Protolabis. The small size of the cranium and coronoid process is correlated with the strong lateral and mesial flare of the mandibular angle in P. coartatus. This reflects increased emphasis on the masseter and pterygoid muscles in mastication and less emphasis on the temporalis. In contrast, the large coronoid process in Procamelus indicates greater emphasis on the temporalis muscle. Oxydactylus exilis Matthew is transferred to Michenia because it shares the derived features of a narrow rostrum, incisiform upper canine, and a shallow symphysis. A new species, Michenia yavapaiensis, with P[subscript]1 unerupted, P[subscript]2 small, unerupted or absent, and tall-crowned molars is described from the Milk Creek Formation. Finally, a cladogram of proposed relationships of the Protolabidini is presented, including Tanymykter, new genus, Protolabis and Michenia with supporting evidence for this tribe being a monophyletic group. The relationship of other members of the Camelinae to the Protolabidini is also discussed. A short section detailing the stratigraphic framework of the Milk Creek Formation, Yavapai County, Arizona is included"--P. 371.Item Michenia, a new protolabine (Mammalia, Camelidae) and a brief review of the early taxonomic history of the genus Protolabis. American Museum novitates ; no. 2444(New York, N.Y. : American Museum of Natural History, 1971) Frick, Childs, 1883-1965.; Taylor, Beryl E."Since Protolabis Cope (1876) was described, species of this genus, including the type species have frequently been confused with those of Procamelus and Miolabis. A brief taxonomic history of Protolabis, as well as a clarification of the type species, is given along with characters that distinguish Protolabis from both Procamelus and Miolabis. Michenia agatensis, a specialized camelid of smaller size, near the base of the evolutionary radiation of the protolabines, is also described. Although its ancestry is unknown, Michenia agatensis more closely resembles Dyseotylopus migrans Stock from the upper part of the Sespe Formation of California than any other known Arikareean camelid"--P. 21-22.Item Miocene Leptomerycidae (Artiodactyla, Ruminantia) and their relationships. American Museum novitates ; no. 2596(New York, N.Y. : American Museum of Natural History, 1976) Taylor, Beryl E.; Webb, S. David (Sawney David), 1936-"Leptomerycidae, previously thought to have survived only from the Arikareean, are here recognized from the medial Miocene (late Hemingfordian into Valentinian) deposits of New Mexico, Texas, and Nebraska. These late-surviving Leptomerycidae belong to the species Pseudoparablastomeryx scotti and P. francesita, previously assigned to the Blastomerycinae. Likewise, Pronodens silberlingi from Arikareean deposits in Montana and possibly South Dakota is transferred to the Leptomerycidae from incertae sedis in the Cervidae. The relationships between these late Leptomerycidae and contemporaneous Blastomerycinae are shown to be remote despite several parallel features in common. Separation of the family Leptomerycidae from the family Hypertragulidae is advocated"--P. [1].Item Phylogenetic systematics of the Borophaginae (Carnivora, Canidae). Bulletin of the AMNH ; no. 243([New York] : American Museum of Natural History, 1999) Wang, Xiaoming, 1957-; Tedford, Richard H.; Taylor, Beryl E."The subfamily Borophaginae (Canidae, Carnivora, Mammalia) was erected by G.G. Simpson in 1945 to include seven genera of large, bone-crushing "dogs" in the late Tertiary of the northern continents. As a monophyletic group of canids, the Borophaginae is now known to be much more diverse than was originally envisioned but is confined within the middle to late Tertiary of North America. Fossil records of the borophagines are well represented and members of this prolific clade are often the most common predators in the late Tertiary deposits. Largely due to the Childs Frick Collection at the American Museum of Natural History, borophagines are represented by some of the best materials among fossil carnivorans in anatomical representation, sample size, and stratigraphic density. As a result of this explosive growth of new information, borophagine systematics is now in need of a complete rethinking at a level that could not have been attempted by previous studies. A detailed study of borophagine phylogenetic systematics is presented here, publishing for the first time the entire Frick Collection. A total of 66 species of borophagines, including 18 new species, ranging from Orellan through Blancan ages, are presently recognized. A phylogenetic analysis of these species is performed using cladistic methods, with Hesperocyoninae, an archaic group of canids, as an outgroup. At its base, the Borophaginae has a sister relationship with the subfamily Caninae, which includes all living canids and their most recent fossil relatives. The Borophaginae-Caninae clade is in turn derived from the subfamily Hesperocyoninae. Apart from some transitional forms, most of the Borophaginae can be organized in four major clades (all erected as new tribes or subtribes): Phlaocyonini, Cynarctina, Aelurodontina, and Borophagina. The Borophaginae begins with a group of small fox-sized genera, such as Archaeocyon, Oxetocyon, Otarocyon, and Rhizocyon, in the Orellan through early Arikareean. Relationships among these genera are difficult to resolve due to their primitiveness. Slightly more derived, but still near the base of the Borophaginae, is the Phlaocyonini, a hypocarnivorous clade of the Arikareean and Hemingfordian that includes Cynarctoides and Phlaocyon. These two genera represent divergent approaches toward hypocarnivory. Species of Cynarctoides trend toward selenodonty and remain small in size, whereas species of Phlaocyon specialize toward bunodont dentitions but of increasing size, with an unusual trend toward hypercarnivory by two terminal species in the clade. Four transitional taxa (species of Cormocyon and Desmocyon) occupy intermediate positions between the Phlaocyonini and Cynarctina, and represent a gradual size increase toward medium-size individuals. The subtribe Cynarctina, the second hypocarnivorous clade, includes Paracynarctus and Cynarctus in the Hemingfordian through Clarendonian, and represents a larger size group than the Phlaocyonini, although there is a tendency toward size reduction among advanced species of Cynarctus. The cynarctines feature the most bunodont dentition known among canids. The next series of transitional taxa (Metatomarctus, Euoplocyon, Psalidocyon, Microtomarctus, Protomarctus, and Tephrocyon) are of medium size and occupy a pectinated sequence that contains a rather diverse set of dental morphology. These include the most hypercarnivorous borophagine Euoplocyon, the peculiarly trenchant Psalidocyon, and the dwarf lineage Microtomarctus. The next clade, Aelurodontina, is the first major hypercarnivorous group and is represented by Tomarctus and Aelurodon in the Barstovian and Clarendonian. The aelurodontines evolve around a more consistent theme of increasingly more hypercarnivorous dentitions with strong premolars, forming a rather linear series from Tomarctus to various species of Aelurodon. The terminal clade Borophagina, sister to the Aelurodontina, begins with the mostly mesocarnivorous Paratomarctus and Carpocyon in the late Barstovian through late Hemphillian. The terminal species of Carpocyon, C. limosus, shows some hypocarnivorous adaptations. Protepicyon in the Barstovian initiates the hypercarnivorous trend in the terminal clade. Epicyon, the largest known canid, is the dominant predator in the Clarendonian and Hemphillian. Finally, an enlarged concept of Borophagus consists of a series of pectinated species terminated by B. diversidens in the late Blancan. Epicyon and Borophagus are the most highly evolved in their capacity to crush bones. Phylogenetic reconstruction was greatly aided by the high quality of fossil records and the large number of transitional forms. The latter ensures a morphological continuity that facilitates the identification of homoplasies that otherwise could easily be mistaken as synapomorphies. Confidence in the phylogeny is further enhanced by a high congruence between the cladistic rank and the stratigraphic sequence. The temporal and morphological continuity in many borophagine lineages also permits further postulation about their evolutionary processes, such as cladogenetic and anagenetic events. Our considerably enlarged concept of the Borophaginae indicates a much broader trophic diversity than has previously been envisioned. In addition to the commonly recognized hyenalike forms, members of the Borophaginae acquired a wider spectrum of morphologies that surpassed either the hesperocyonine or canine canids. The Borophaginae played broad ecological roles that are performed by at least three living carnivoran families, Canidae, Hyaenidae, and Procyonidae"--P. 9-10.Item Phylogenetic systematics of the North American fossil Caninae (Carnivora, Canidae). (Bulletin of the American Museum of Natural History, no. 325)([New York] : American Museum of Natural History., 2009) Tedford, Richard H.; Wang, Xiaoming, 1957-; Taylor, Beryl E.The canid subfamily Caninae includes all the living canids and their most recent fossil relatives. Their sister taxon is the Borophaginae with which they share an important modification of the lower carnassial, namely the presence of a bicuspid talonid, which gives this tooth an additional function in mastication. Contributing to this function is the enlargement of the posterolingual cingulum of M1 and development of a hypocone. The Caninae diverged from the Borophaginae in the narrowing and elongation of the premolars separated by diastemata and placed in a shallow ramus and narrow muzzle. These latter features allow the Caninae to be recognized in the fossil record as early as the beginning of the Oligocene ‪(‬34 Ma‪)‬ and constitute evidence that they represent a monophyletic group. In striking contrast to the history of the Borophaginae, the Caninae remain confined to a closely similar group of fox-sized species ‪(‬Leptocyon spp.‪)‬ throughout the Oligocene and showing very limited cladogenesis into the end of the medial Miocene ‪(‬12 Ma‪)‬, a span that saw marked adaptive divergence in the Borophaginae and the origin of all its major clades. By 12 Ma ‪(‬beginning of the Clarendonian Land Mammal age‪)‬ few fox-sized borophagines remained and most of those held hypocarnivorus adaptations. At that point the Vulpini appear both as mesocarnivores ‪(‬Vulpes spp.‪)‬ and hypocarnivores ‪(‬Metalopex spp.‪)‬ reproducing, on a much smaller scale, the range of adaptations shown in the initial radiation of the Borophaginae. By the end of the Clarendonian ‪(‬9 Ma‪)‬ the first members of the tribe Canini appear. Initially this group was represented by the genus Eucyon, largely by a single widespread North American species E. davisi. Our cladistic analysis predicts that the roots of the South American clade subtribe Cerdocyonina, sister taxon to E. davisi and Canis species ‪(‬together, subtribe Canina‪)‬, must also have been present, but taxa representing this group do not appear in the North America record until the earliest Pliocene ‪(‬latest Hemphillian, 5 Ma‪)‬. Species of three genera ‪(‬Cerdocyon, Chrysocyon, and possibly Theriodictis‪)‬, now confined to South America, appear in the fossil record of the southern United States and northern Mexico prior to and just after the opening of the Panamanian Isthmus ‪(‬ca. 3 Ma‪)‬, indicating that important cladogenesis within the South American clade took place in North America. Species of Eucyon make their appearance in the Old World in the late Miocene, and E. davisi has a Pliocene record in Asia. Species of this genus undergo a modest adaptive radiation in Eurasia during the Pliocene. In the late Miocene and early Pliocene two species of Canis appear in North America ‪(‬C. ferox and C. lepophagus‪)‬, representing the initial cladogenesis within the genus. These animals are all coyote-sized and represent a broadening of body size range within a mesocarnivorous dental adaptation. Toward the end of the Pliocene and into the Pleistocene in North America a curious and rare group of jackal-like species ‪(‬C. tho¨oides, C. feneus, and C. cedazoensis‪)‬ seem to form an endemic clade arising near C. lepophagus. These taxa are dentally similar to jackals, especially C. aureus, but share no synapomorphies with them. The early cladogenesis of Canis in the Pliocene of North America produced a somewhat larger form, C. edwardii, that appears in the late Blancan at ca. 3 Ma. It also seems to have a sister relationship with C. lepophagus and with the coyote C. latrans, which appears much later in the record ‪(‬late Irvingtonian‪)‬ and quickly becomes distributed across the United States. The golden jackal ‪(‬C. aureus‪)‬ shares synapomorphies with the coyote and C. edwardii but does not appear in the fossil record until the early Pleistocene of North Africa. Canis edwardii is extinct by the end of the Irvingtonian. Large wolflike species of Canis seem to be the products of evolution in Eurasia. They appear early in the North American record as immigrants of the crown group of Canis that augment the essentially stem group native species of the New World. The first of these is Canis armbrusteri, which appears early in the Irvingtonian, initially in the Southwest but later in the eastern United States where it survived into the early Rancholabrean of Florida. This is a large wolf, a sister taxon of C. lupus, whose appearance early in the Pleistocene predates the earliest midcontinent occurrence of C. lupus by nearly 1 m.y. In the New World C. armbrusteri gave rise to the native dire-wolf ‪(‬C. dirus‪)‬, as evidenced by intergrading morphologies of late Irvingtonian examples that show the transformation to the more hypercarnivorous giant form. The earliest evidence of C. dirus is in the midcontinent and it appears to have displaced C. armbrusteri into the eastern part of the continent while it expanded westward and particularly southward into South America during the late Pleistocene. Canis lupus itself does not appear in midlatitude North America until the late Rancholabrean ‪(‬0.1 Ma, last glacial cycle‪)‬, although it was a resident of Arctic North America since the mid-Pleistocene ‪(‬ca. 0.8 Ma‪)‬. North America has a limited record of canine diversity during the Pleistocene. Most clades of vulpines and canines that reached the Old World during that span underwent significant cladogenesis so that the canid fauna of Eurasia was always more diverse than that of the New World. From time to time waifs from the Old World centers of origin wandered south into midcontinent North America to briefly enrich the fossil record: Xenocyon spp. in the late Irvingtonian; Cuon alpinus and Canis lupus in the late Rancholabrean, along with the living fox species Vulpes vulpes ‪(‬late Rancholabrean‪)‬ and perhaps the swift-fox earlier in the Pleistocene. The center of evolution of the Caninae thus shifted to Eurasia and to South America when avenues of dispersal to those continents were available at the end of the Cenozoic. Because of the diversity of Old World forms that became resident in North America, our analysis of the New World fauna has been expanded to include relevant Old World taxa and to present a broader phylogenetic reconstruction than could be offered only on the basis of strictly New World evidence. This expanded view brings in a greater diversity of morphology, which allows us to better separate homoplasy from true homology. We have considered only Old World taxa that are represented by the most complete material so that missing data are kept to a minimum in our analysis. This still affords sufficient taxa so that the major structure of the phylogeny of Canis can be discerned. Our cladistic analysis found two robustly recognized crown clades within Canis: the mesocarnivorous lupus clade, and the hypercarnivorous Xenocyon clade. The first contains the wolf, C. lupus, and its sister taxon C. armbrusteri + C. dirus, with the latter showing some dental features related to hypercarnivory as an autapomorphy. The Chinese late Pliocene wolf C. chihliensis appears to be a stem group in the Lupus clade and may be closely allied to C. armbrusteri. The Xenocyon clade is also Eurasian in origin and is marked by character reversals to states primitive within Canis. Its earliest record is in the medial Pliocene of eastern Asia ‪(‬Xenocyon dubius‪)‬, after which it dispersed to western Eurasia in the early Pleistocene ‪(‬X. lycaonoides‪)‬. In the Pleistocene Xenocyon achieved a Holarctic distribution including midlatitide North America ‪(‬X. texanus and X. lycaonoides‪)‬. During this episode of expansion the sister taxa Cuon and Lycaon arose in Eurasia and Africa, respectively, most likely from isolated Xenocyon populations. In the latest Pleistocene Cuon alpinus expanded its range into the middle latitudes of the New World. A number of Pliocene and Pleistocene wolf and coyote-sized Eurasian Canis species ‪(‬C. arnensis, C. etruscus, C. palmidens, C. mosbachensis, and C. variabilis‪)‬ were included in our cladistic analysis, but the relationships of those forms were difficult to resolve beyond their paraphyletic relationship to the crown clade.Item The phylogeny of hornless ruminants and a description of the cranium of Archaeomeryx. Bulletin of the AMNH ; v. 167, article 3(New York : American Museum of Natural History, 1980) Webb, S. David (Sawney David), 1936-; Taylor, Beryl E."We analyze the interrelationships of the several groups of hornless ruminants and show which of them lie nearest the higher ruminants. The phylogenetic progression within Ruminantia proceeds from Hypertragulidae through Tragulidae to Leptomerycidae to Gelocidae to Moschidae and thence to the horned ruminants. Archaeomeryx of the late Eocene is recognized as a primitive member of the Leptomerycidae; the living Tragulidae actually represent a more primitive ruminant stock. We introduce the name Moschina for the Gelocidae and the Moschidae and the term Eupecora for the higher ruminant groups bearing horns, antlers, and ossicones. We also propose Neoselenodontia, above the subordinal level, to include both the Ruminantia and their sister group, the Tylopoda. The stratigraphic records of the five lower ruminant families appear relatively complete with the exception of the Tragulidae, which are poorly known prior to the Miocene. The exclusively North American distribution of the family Hypertragulidae and many of the Tylopoda suggests that the Ruminantia may have originated in North America. The Tragulidae, exclusively Old World and predominantly subtropical, presumably originated by colonization and isolation in the Old World. Thereafter ruminant evolution centered in the Old World, but representatives of every major group reached North America"--P. 121.Item Phylogeny of the Caninae (Carnivora, Canidae) : the living taxa. American Museum novitates ; no. 3146(New York, N.Y. : American Museum of Natural History, 1995) Tedford, Richard H.; Taylor, Beryl E.; Wang, Xiaoming, 1957-"Fifty-seven characters of the skull, mandible, dentition, and postcranium distributed among 122 character states obtained from specimens representing 15 living genera of the canid subfamily Caninae (67% of which are monotypic) were subjected to cladistic analysis assisted by a maximum-parsimony computer program (HENNIG86). The program found a single tree, 90 steps in length with a consistency index of 65 and retention index of 78. The reconstruction delineates two sister taxa: the foxlike tribe Vulpini, and the wolflike and South American taxa, tribe Canini. This division is also supported by karyological and biomolecular studies although the composition of each group varies with the evidence used. The osteological evidence leads to a more fully resolved relationship than presently available from other systems. Problem taxa include the foxes Urocyon and Otocyon, considered sister taxa, and members of the Vulpini clade osteologically, but either as members of the Canini clade (with Fennecus) on chromosome morphology or in a basal unresolved multichotomy with other canines on allozyme evidence. More contentious is the position of the Asian raccoon-dog Nyctereutes, placed as a sister taxon of the South American crab-eating 'fox' Cerdocyon in our analysis but allied with Vulpes on karyological evidence or a part of the basal canine multichotomy with regard to the allozyme results. The South American bush-dog Speothos, a hypercarnivore, is placed on osteological grounds in a clade with the rest of the South American genera in agreement with chromosome evidence although allozymes relate it to the Canis group. Despite these individual cases there is reasonable concordance in the conclusions drawn from the three lines of phyletic inference. Previous neontological and paleontological studies of canines have not clarified relationships within this group"--P. [1].Item The Protoceratinae (Mammalia, Tylopoda, Protoceratidae) and the systematics of the Protoceratidae. Bulletin of the AMNH ; v. 150, article 4(New York : [American Museum of Natural History], 1973) Patton, Thomas Hudson, 1934-; Taylor, Beryl E."The systematics of the subfamily Protoceratinae are revised and its evolution, phylogeny, and zoogeography outlined. The stratigraphic range of the subfamily extends from the Chadronian (early Oligocene) to the Clarendonian (middle Pliocene); geographically, the subfamily ranges from the northern Great Plains (South Dakota, Nebraska, Wyoming) southward to Texas and into Panama. The Protoceratinae now include four genera: Heteromeryx, Pseudoprotoceras, Protoceras, and Paratoceras. Calops Marsh is here synonymized with Protoceras; specific synonymies within each genus are also treated. Two new species of Protoceras are recognized: P. skinneri from South Dakota and Nebraska and P. neatodelpha from Wyoming. New skull and horn material allows an expanded description and diagnosis of Paratoceras, and a new species, P. wardi, from the Barstovian of the Texas Gulf Coastal Plain is erected"--P. 351.Item A revision of the geology and paleontology of the Bijou Hills, South Dakota. American Museum novitates ; no. 2300(New York, N.Y. : American Museum of Natural History, 1967) Skinner, Morris F.; Taylor, Beryl E.; Gidley, James Williams, 1866-1931.; Matthew, William Diller, 1871-1930.Item The Synthetoceratinae (Mammalia, Tylopoda, Protoceratidae). Bulletin of the AMNH ; v. 145, article 2(New York : [American Museum of Natural History], 1971) Patton, Thomas Hudson, 1934-; Taylor, Beryl E."The subfamily Synthetoceratinae, a group of uniquely horned North American Tertiary ruminants, marks the evolutionary culmination of the family Protoceratidae. In addition to a pair of widely curved postorbital horns this family is characterized by the development of protruding bony plates on the upper surface of the maxillaries that phyletically unite to form a common-trunked rostral horn, a feature that has no parallel among other horned ruminants. Members of the North American endemic subfamily are distributed from South Dakota to Texas, eastward across the Gulf Coast to Florida, and north into New Jersey. Temporally, they ranged from the late Arikareean of the northern Great Plains to the early Hemphillian of the Gulf Coastal Plain. Taxonomic changes within the subfamily, Synthetoceratinae, include (1) the transfer of Syndyoceras from the monotypic subfamily, Syndyoceratinae, to the Synthetoceratinae, (2) the placement of Stirton's genus, Lambdoceras, in synonymy with Prosynthetoceras but retaining it as a subgenus (Prosynthetoceras (Lambdoceras)), and (3) the synonymy of Prosynthetoceras siouxensis dawesensis Frick with Prosynthetoceras (Lambdoceras) siouxensis Frick. As now defined, the subfamily includes three genera: Syndyoceras Barbour, Prosynthetoceras Frick, and Synthetoceras Stirton. Syndyoceras, the earliest occurring genus, is the first protoceratid to possess a single-trunked rostral horn. Monotypic Syndyoceras (S. cooki) is found only in the northern Great Plains. Prosynthetoceras, on the other hand, is by far the most widely dispersed genus in the subfamily, occurring in the Great Plains, and in the Gulf and Atlantic coastal plains. The genus is herein divided into two mostly allopatric subgenera: Prosynthetoceras (Prosynthetoceras), including P. (P.) texanus and P. (P.) francisi, and Prosynthetoceras (Lambdoceras), including P. (L.) hessei, P. (L.) siouxensis and P. (L.) trinitiensis. The type subgenus is restricted to the Gulf Coastal Plain, whereas P. (Lambdoceras) is distributed in both the northern Great Plains and in the Texas Coastal Plain. The latest occurring and most advanced member of the lineage is the monotypic genus Synthetoceras (S. tricornatus), which is restricted to Texas and the Gulf Coastal Plain. Evolutionary changes in the Synthetoceratinae involved (1) increased total body size, (2) increased length of the shaft of the rostral horn, (3) lengthened diastemata, (4) reduced premolars, (5) taller-crowned molars, and (6) reduced lateral metapodials. Whereas early synthetoceratine evolution took place in the Great Plains, an early dispersal, (?early Hemingfordian), brought the ancestors of the Prosynthetoceras lineage to the Texas Gulf Coastal Plain where they eventually spread eastward into Florida and northeastward along the Atlantic Coastal Plain. The P. (Lambdoceras) group, however, remained in the Great Plains during most of its evolutionary history and is recognized only in early Barstovian deposits on the Texas coast. Synthetoceras, the direct descendant of Prosynthetoceras, flourished throughout the Gulf Coastal Plain; some populations spread north into the southern Great Plains, where they are preserved in the Clarendonian of the Texas panhandle, and others persisted, at least in Florida, until the early Hemphillian"--P. 216.