Browsing by Author "Lieberman, Bruce S."
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Item Devonian calmoniid trilobites from the Parnaíba Basin, Piauí State, Brazil. American Museum novitates ; no. 3192(New York, N.Y. : American Museum of Natural History, 1997) Carvalho, Maria Da Gloria Pires De.; Edgecombe, Gregory D.; Lieberman, Bruce S.Item Evolution of the trilobite subfamily Proetinae Salter, 1864, and the origin, diversification, evolutionary affinity, and extinction of the Middle Devonian proetid fauna of eastern North America. Bulletin of the AMNH ; no. 223([New York] : American Museum of Natural History, 1994) Lieberman, Bruce S."This study considers the biogeographic origins, evolutionary affinities, and patterns of diversification and extinction in a portion of the Lower and Middle Devonian proetid trilobite fauna of eastern North America. Four generic clades comprising about 45 species are known from the strata of the upper Emsian (Sawkillian) Bois Blanc Limestone and Schoharie Grit, the Eifelian (Southwoodian) Onondaga Limestone, and the Givetian (Cazenovian, Tioughniogan, Taghanic) Hamilton Group. These taxa have traditionally been assigned to the subfamilies Proetinae Salter, 1864, and/or Dechenellinae Pribyl, 1946. These are Crassiproetus Stumm, 1953a, Basidechenella Richter, 1912, Dechenella Kayser, 1880, and Monodechenella Stumm, 1953a, which were originally considered to be closely related. A higher-level phylogenetic analysis of the Proetinae is conducted to see if these taxa were indeed closely related and thus represent a single endemic radiation of species in eastern North America or rather a series of independent lineages in that region. In the course of discerning characters that defined the Proetinae, it was discovered that Monodechenella lacks several of the characters that define the Proetinae, and the members of this genus therefore must be excluded from this subfamily. They instead appear to belong to a larger group informally referred to as the 'Thebanaspis clade,' which appears to be closely related to the Proetinae. A phylogenetic analysis is performed on proetine ingroup taxa using 21 taxa and 53 characters, and several of the major generic clades in the Proetinae are considered. The phylogenetic analysis of the Proetinae is used to ascertain the ancestral biogeographic states for the three genera in the Proetinae that form an important component of the Lower and Middle Devonian trilobite fauna of eastern North America. This information is used to determine if these taxa are ancestrally present in eastern North America or rather represent a series of invasions from other biogeographic regions. Other taxa occurring in eastern North America at this time appear to represent elements that invaded from Armorica. This invasion of taxa has been related to the collision between plates that produced the Acadian Orogeny during the Middle Devonian. Patterns in these proetid taxa are compared with those known for other groups to ascertain what control the Acadian Orogeny as a biogeographic event may have had on the appearance of these taxa in eastern North America. Phylogenetic analysis is then performed on all available species in each of these generic clades that occur in eastern North America. Species that belong to these clades but which hail from other biogeographic regions are also considered. These phylogenies were used to assess macroevolutionary patterns such as diversification and extinction within each of these clades in eastern North America. In addition to being an important paleogeographic event, the Acadian Orogeny also caused major paleoenvironmental changes. The impact of these changes on the proetid fauna of eastern North America is assessed. It appears that a phenomenon analogous to Vrba's (1985, 1992) Turnover Pulse Hypothesis may have mediated elevated speciation rates in the proetid taxa over the period considered. However, eventually the profound changes in environment appear to have led to the extinction of much of the proetid trilobite fauna of eastern North America. Information on patterns of occurrence in different geographic regions is combined with information from the phylogenetic analyses of the individual generic clades to consider large-scale biogeographic patterns in the late Lower and Middle Devonian. A method for considering biogeographic patterns using cladistic information is developed. This method is based on Brooks Parsimony Analysis, but it allows multiple events of range expansion and subsequent vicariant splitting to occur within each generic clade. This biogeographic method was used to evaluate the relationships between the Arctic, Armorican, and eastern North American paleobiogeographic regions. The relationships between the different major sedimentary basins in eastern North America, the Appalachian, Illinois, and Michigan basins, are also considered. Finally, the origin of major evolutionary faunas in the fossil record is discussed. Included is a brief discussion of a depauperate proetid fauna of the Emsian and Eifelian whose members do not belong to the four generic clades considered in detail. In this work four new genera are recognized: Plesiowensus, Arcticormistonia, Aayemenaytcheia, and Milesdavis. In addition, 12 new species are described: Arcticormistonia edgecombei, Crassiproetus halliturgidus, C. neoturgidus, C. stummi, C. schohariensis, Basidechenella cartwrightae, B. timwhitei, Dechenella perscheii, D. carvalhoae, Pedinodechenella modelli, Milesdavis eldredgei, and Monodechenella legrandsmithi. Diagnoses and discussions for all of the taxa considered are presented"--P. 4.Item Evolutionary and biogeographic patterns in the Asteropyginae (Trilobita, Devonian) Delo, 1935. Bulletin of the AMNH ; no. 232([New York] : American Museum of Natural History, 1997) Lieberman, Bruce S.; Kloc, Gerald J."This paper presents a phylogenetic analysis of the Asteropyginae Delo, 1935. Sixty-six characters and 39 taxa were employed in a cladistic analysis that produced a single most parsimonious tree that is presented as a hypothesis of asteropyginid relationships. In addition to the phylogeny generated, 11 new genera are diagnosed: Philipsmithiana, Coltraneia, Stummiana, Bellacartwrightia, Deloops, Tolkienia, Braunops, Armorigreenops, Kennacryphaeus, Modellops, and Hallandclarkeops, and 12 new species are described: Philipsmithiana hyfinkeli, P. burtandmimiae, Armorigreenops leoi, Pelitlina smeenki, Bellacartwrightia jennyae, B. whiteleyi, B. phyllocaudata, B. calderonae, Greenops widderensis, G. barberi, G. grabaui, and Kennacryphaeus harrisae. Traditionally, asteropyginine taxa in the Appalachian and Michigan Basins of Eastern North America had been assigned to Greenops Delo, 1935, or Greenops (Neometacanthus) Richter and Richter, 1948. A core of five Eastern North American species--Greenops boothi (Green, 1837), G. widderensis, new species, G. chilmanae Stumm, 1965, G. grabaui, new species, and G. barberi, new species--can still be assigned to Greenops. All other asteropyginine taxa in Eastern North America must be assigned to different genera. Species referable to Neometacanthus Richter and Richter, 1948, may be known from the Illinois Basin of Eastern North America, and a species referable to Tolkienia, new genus, may be known from the Michigan Basin of Eastern North America. The single most parsimonious cladogram was also used to investigate biogeographic patterns. In particular, the number of times that independent lineages of asteropyginines invaded from what are now Europe and North Africa (called Armorica herein) into Eastern North America during the Devonian was ascertained. Phylogenetic analysis suggested that there must have been at least four such invasions, with clades that had primitive European or North African affinities giving rise to Eastern North American taxa, although no species are shared between Armorica and Eastern North America. One of the lineages that invaded Eastern North America subsequently reinvaded Armorica. The timing of these invasions and their relation to overall patterns of faunal evolution in the Middle Devonian of Eastern North America are also discussed. These patterns suggest that the different taxa that make up a fauna often arrive during different time intervals, not all at once"--P. 3.Item Patterns and processes of stasis in two species lineages of brachiopods from the Middle Devonian of New York State. American Museum novitates ; no. 3114(New York, N.Y. : American Museum of Natural History, 1994) Lieberman, Bruce S.; Brett, Carlton E. (Carlton Elliot); Eldredge, Niles.