Evolution of the horse has been an often-cited primary example of evolution, as well as one of th... more Evolution of the horse has been an often-cited primary example of evolution, as well as one of the classic and important stories in paleontology for over a century and a half, due to their rich fossil record across 5 continents: North America, South America, Europe, Asia and Africa. The recent horse has served a profound role in human ancestry, including agriculture, commerce, sport, transport, warfare, and in prehistory, for the subsistence of humans. Many studies have examined the evolution of the Equidae and chronicled the striking changes in skulls, dentition, limbs, and body size which have long been perceived to be a response to environmental shifts through time. Most comprehensive studies heretofore have: (1) focused on the “Great Transformation”- changes that occurred in the early Miocene, (2) involved tracking long-term diversity or paleoecological trends on a single continent or within a geographical locality, or (3) concentrated on the 3-toed hipparions. The Plio–Pleistocene evolutionary stage of horse evolution is punctuated by the great climatic fluctuations of the Quaternary beginning 2.6 Ma which influenced Equus evolution, biogeographic dispersion and adaptation on a nearly global scale. The evolutionary biology of Equus evolution across its entire range remains relatively poorly understood and often highly controversial. Some of this lack of understanding is due to assumptions that have arisen because of the relatively derived craniodental and postcranial anatomy of Equus and its close relatives which has seemed to imply that that these forms occupied relatively homogenous and narrow dietary and locomotor niches - notions that have not been adequately addressed and rigorously tested. Other challenges have revolved around teasing apart environmentally-driven adaptation versus phylogenetically defined morphological change. Geochronologic age control of localities, geographic provinces and continents has improved, but in no way is absolute and can be reexamined in our proposed volume. Temporal resolution for paleodietary, paleohabitat and paleoecological interpretations are also challenging for understanding the evolution of Equus. Our proposed volume attempts to assemble a group of experts who will address multiple dimensions of Equus’ evolution in time and space
A new method of scoring dental microscopic use wear, initially developed for and applied to extan... more A new method of scoring dental microscopic use wear, initially developed for and applied to extant and extinct ungulates, is here applied to primates, and the efficacy of the method as a tool for diagnosing diet in both ungulates and primates is established. The method employs standard refractive light microscopy instead of scanning electron microscopy (SEM), and all use-wear features are counted or scored under low magnification (35×). We use measurement systems analysis (variance components analysis of sources of ...
A large sample (N=76) of Pleistocene mastodon (Mammut americanum) teeth from a variety of localit... more A large sample (N=76) of Pleistocene mastodon (Mammut americanum) teeth from a variety of localities in Florida were analyzed for dental enamel microwear features via low-magnification stereomicroscopy. Second upper and lower molars were used for dental dietary reconstruction purposes to allow comparison of results to an extensive molar microwear database comprised of extant taxa with well-studied diets. Deciduous premolars and
A large sample of the Pikermi and Samos ungulates was examined by microwear analysis using a ligh... more A large sample of the Pikermi and Samos ungulates was examined by microwear analysis using a light stereomicroscope (561 extinct and 809 extant comparative specimens). The results were used to infer the dietary adaptations of individual species and to evaluate the Pikermian Biome ungulate fauna. Many of the bovids have wear consistent with mixed feeding, although a few mesodont taxa apparently enjoyed an exclusive browsing and or grazing diet. The giraffids spanned the entire dietary spectrum of browsing, mixed feeding, and grazing, but most of the three-toed horses (Hippotherium) were hypsodont grazers. The colobine monkeyMesopithecus pentelicidisplays microwear consistent with a mixed fruit and leaf diet most likely including some hard objects. Similar results were obtained from prior scanning electron microscopy microwear studies at 500 times magnification and from the light microscope method at 35 times magnification for the same species. Results show that diet can differ between species that have very similar gross tooth morphology. Our results also suggest that the Pikermian Biome was most likely a woodland mosaic that provided a diversity of opportunities for species that depended on browsing as well as species that ate grass. The grasses were most likely C3grasses that would grow in shaded areas of the woodland, glades, and margins of water. The ungulate component of the Pikermi and Samos fauna was more species-rich and more diverse in diet than the ungulates observed in modern African forests, woodlands, or savannas, yet dietarily most similar to the ungulates found in woodland elements of India and to some extent of Africa. It is unlikely that the Pikermi and Samos ungulates inhabited dense forests because we find no evidence for heavy fruit browsing. Conversely, a pure savanna is unlikely because many mixed feeders are present as well as browsers. Extant woodland African species are morphologically and trophically very similar to the African savanna species. Therefore the evolution of grazing and of hypsodont morphology for Africa may have evolved within the Plio-Pleistocene woodlands of Africa. Our results show that major dietary and morphologic ungulate evolution may take place within woodlands rather than as a consequence of species moving into savannas both during the late Miocene of Pikermi and Samos and during the Pleistocene–Recent of Central Africa.
Dietary adaptations of both Tertiary and Quaternary representatives of North American Camelidae w... more Dietary adaptations of both Tertiary and Quaternary representatives of North American Camelidae were examined through deep evolutionary time (via hypsodonty index), though ecological time (via mesowear analysis), and through the last few days of life (via microwear) by ...
A new method of scoring dental microscopic use wear, initially developed for and applied to extan... more A new method of scoring dental microscopic use wear, initially developed for and applied to extant and extinct ungulates, is here applied to primates, and the efficacy of the method as a tool for diagnosing diet in both ungulates and primates is established. The method employs standard refractive light microscopy instead of scanning electron microscopy (SEM), and all use-wear features are counted or scored under low magnification (35 x). We use measurement systems analysis (variance components analysis of sources of measurement error) to evaluate the consistency and reproducibility of measurements using this method. The method is shown to have low intra- and inter-observer measurement error, and to effectively distinguish among graminivores, folivores, and frugivores. It can also be used to identify seed predators and to diagnose hard-object feeding. The method is also shown to be robust to the selection of measurement site; it works equally well when applied to upper or to lower molars. Finally, we use analysis of variance to examine the consistency of the signals across mammalian orders, and discriminant function analysis to develop dietary diagnostic tools for a set of "classified" primates with known diets. We test the success of these tools not merely by examining their a posteriori classification "success," but by using them to construct predicted dietary profiles for a sample of unclassified extant primate species, again with known diets.
The paleodiet of the shovel-tusked gomphotheres from Florida (Amebelodon floridanus, Konobelodon ... more The paleodiet of the shovel-tusked gomphotheres from Florida (Amebelodon floridanus, Konobelodon britti, and Serbelodon barbourensis) was assessed via microwear analysis of molar dental enamel and compared to a large database of both extant proboscideans and ungulates. Scratch and pit results show a consistent browsing signal in A. floridanus, K. britti and S. barbourensis. Fossil results are more similar to those of the extant Loxodonta cyclotis than to Loxodonta africana or Elephas maximus, the latter two taxa exhibiting a mixed feeding result. Scratch width scores are high in all three shovel tuskers as well as in the extant proboscideans indicating the ingestion of some coarse vegetation, most likely bark, and twigs. Gouging is relatively low in A. floridanus and S. barbourensis. Only K. britti has levels of gouging approximating that seen in extant elephants. Large pitting is relatively low in both fossil and extant forms although L. cyclotis has higher levels of large pitting ...
The Cioburciu hipparions, Republic of Moldova, are included in a Turolian assemblage, approximate... more The Cioburciu hipparions, Republic of Moldova, are included in a Turolian assemblage, approximately dated between 9 and 7 million years. We assess herein their taxonomic position, systematics, biogeography and paleodietary habits. We have undertaken standard equid measurements as well as accessing the Vera Eisenmann website for measurements and images and analysed craniodental and postcranial elements. This assemblage has been determined to be of a medium-sized hipparion with an elongated muzzle, well developed preorbital fossa that is dorsoventrally extensive and placed close to the orbit, lacking a caninus fossa and having a prominent and deep buccinator fossa. As such, this assemblage is referable to Cremohipparion moldavicum Gromova 1952 common to the Western Ukraine, Balkans, Romania, Republic of Georgia, Turkey and Iran. We have employed a combination of gross cheek tooth wear morphology utilizing the mesowear method and a microscopic analysis of occlusal enamel scars utilizin...
Evolution of the horse has been an often-cited primary example of evolution, as well as one of th... more Evolution of the horse has been an often-cited primary example of evolution, as well as one of the classic and important stories in paleontology for over a century and a half, due to their rich fossil record across 5 continents: North America, South America, Europe, Asia and Africa. The recent horse has served a profound role in human ancestry, including agriculture, commerce, sport, transport, warfare, and in prehistory, for the subsistence of humans. Many studies have examined the evolution of the Equidae and chronicled the striking changes in skulls, dentition, limbs, and body size which have long been perceived to be a response to environmental shifts through time. Most comprehensive studies heretofore have: (1) focused on the “Great Transformation”- changes that occurred in the early Miocene, (2) involved tracking long-term diversity or paleoecological trends on a single continent or within a geographical locality, or (3) concentrated on the 3-toed hipparions. The Plio–Pleistocene evolutionary stage of horse evolution is punctuated by the great climatic fluctuations of the Quaternary beginning 2.6 Ma which influenced Equus evolution, biogeographic dispersion and adaptation on a nearly global scale. The evolutionary biology of Equus evolution across its entire range remains relatively poorly understood and often highly controversial. Some of this lack of understanding is due to assumptions that have arisen because of the relatively derived craniodental and postcranial anatomy of Equus and its close relatives which has seemed to imply that that these forms occupied relatively homogenous and narrow dietary and locomotor niches - notions that have not been adequately addressed and rigorously tested. Other challenges have revolved around teasing apart environmentally-driven adaptation versus phylogenetically defined morphological change. Geochronologic age control of localities, geographic provinces and continents has improved, but in no way is absolute and can be reexamined in our proposed volume. Temporal resolution for paleodietary, paleohabitat and paleoecological interpretations are also challenging for understanding the evolution of Equus. Our proposed volume attempts to assemble a group of experts who will address multiple dimensions of Equus’ evolution in time and space
A new method of scoring dental microscopic use wear, initially developed for and applied to extan... more A new method of scoring dental microscopic use wear, initially developed for and applied to extant and extinct ungulates, is here applied to primates, and the efficacy of the method as a tool for diagnosing diet in both ungulates and primates is established. The method employs standard refractive light microscopy instead of scanning electron microscopy (SEM), and all use-wear features are counted or scored under low magnification (35×). We use measurement systems analysis (variance components analysis of sources of ...
A large sample (N=76) of Pleistocene mastodon (Mammut americanum) teeth from a variety of localit... more A large sample (N=76) of Pleistocene mastodon (Mammut americanum) teeth from a variety of localities in Florida were analyzed for dental enamel microwear features via low-magnification stereomicroscopy. Second upper and lower molars were used for dental dietary reconstruction purposes to allow comparison of results to an extensive molar microwear database comprised of extant taxa with well-studied diets. Deciduous premolars and
A large sample of the Pikermi and Samos ungulates was examined by microwear analysis using a ligh... more A large sample of the Pikermi and Samos ungulates was examined by microwear analysis using a light stereomicroscope (561 extinct and 809 extant comparative specimens). The results were used to infer the dietary adaptations of individual species and to evaluate the Pikermian Biome ungulate fauna. Many of the bovids have wear consistent with mixed feeding, although a few mesodont taxa apparently enjoyed an exclusive browsing and or grazing diet. The giraffids spanned the entire dietary spectrum of browsing, mixed feeding, and grazing, but most of the three-toed horses (Hippotherium) were hypsodont grazers. The colobine monkeyMesopithecus pentelicidisplays microwear consistent with a mixed fruit and leaf diet most likely including some hard objects. Similar results were obtained from prior scanning electron microscopy microwear studies at 500 times magnification and from the light microscope method at 35 times magnification for the same species. Results show that diet can differ between species that have very similar gross tooth morphology. Our results also suggest that the Pikermian Biome was most likely a woodland mosaic that provided a diversity of opportunities for species that depended on browsing as well as species that ate grass. The grasses were most likely C3grasses that would grow in shaded areas of the woodland, glades, and margins of water. The ungulate component of the Pikermi and Samos fauna was more species-rich and more diverse in diet than the ungulates observed in modern African forests, woodlands, or savannas, yet dietarily most similar to the ungulates found in woodland elements of India and to some extent of Africa. It is unlikely that the Pikermi and Samos ungulates inhabited dense forests because we find no evidence for heavy fruit browsing. Conversely, a pure savanna is unlikely because many mixed feeders are present as well as browsers. Extant woodland African species are morphologically and trophically very similar to the African savanna species. Therefore the evolution of grazing and of hypsodont morphology for Africa may have evolved within the Plio-Pleistocene woodlands of Africa. Our results show that major dietary and morphologic ungulate evolution may take place within woodlands rather than as a consequence of species moving into savannas both during the late Miocene of Pikermi and Samos and during the Pleistocene–Recent of Central Africa.
Dietary adaptations of both Tertiary and Quaternary representatives of North American Camelidae w... more Dietary adaptations of both Tertiary and Quaternary representatives of North American Camelidae were examined through deep evolutionary time (via hypsodonty index), though ecological time (via mesowear analysis), and through the last few days of life (via microwear) by ...
A new method of scoring dental microscopic use wear, initially developed for and applied to extan... more A new method of scoring dental microscopic use wear, initially developed for and applied to extant and extinct ungulates, is here applied to primates, and the efficacy of the method as a tool for diagnosing diet in both ungulates and primates is established. The method employs standard refractive light microscopy instead of scanning electron microscopy (SEM), and all use-wear features are counted or scored under low magnification (35 x). We use measurement systems analysis (variance components analysis of sources of measurement error) to evaluate the consistency and reproducibility of measurements using this method. The method is shown to have low intra- and inter-observer measurement error, and to effectively distinguish among graminivores, folivores, and frugivores. It can also be used to identify seed predators and to diagnose hard-object feeding. The method is also shown to be robust to the selection of measurement site; it works equally well when applied to upper or to lower molars. Finally, we use analysis of variance to examine the consistency of the signals across mammalian orders, and discriminant function analysis to develop dietary diagnostic tools for a set of "classified" primates with known diets. We test the success of these tools not merely by examining their a posteriori classification "success," but by using them to construct predicted dietary profiles for a sample of unclassified extant primate species, again with known diets.
The paleodiet of the shovel-tusked gomphotheres from Florida (Amebelodon floridanus, Konobelodon ... more The paleodiet of the shovel-tusked gomphotheres from Florida (Amebelodon floridanus, Konobelodon britti, and Serbelodon barbourensis) was assessed via microwear analysis of molar dental enamel and compared to a large database of both extant proboscideans and ungulates. Scratch and pit results show a consistent browsing signal in A. floridanus, K. britti and S. barbourensis. Fossil results are more similar to those of the extant Loxodonta cyclotis than to Loxodonta africana or Elephas maximus, the latter two taxa exhibiting a mixed feeding result. Scratch width scores are high in all three shovel tuskers as well as in the extant proboscideans indicating the ingestion of some coarse vegetation, most likely bark, and twigs. Gouging is relatively low in A. floridanus and S. barbourensis. Only K. britti has levels of gouging approximating that seen in extant elephants. Large pitting is relatively low in both fossil and extant forms although L. cyclotis has higher levels of large pitting ...
The Cioburciu hipparions, Republic of Moldova, are included in a Turolian assemblage, approximate... more The Cioburciu hipparions, Republic of Moldova, are included in a Turolian assemblage, approximately dated between 9 and 7 million years. We assess herein their taxonomic position, systematics, biogeography and paleodietary habits. We have undertaken standard equid measurements as well as accessing the Vera Eisenmann website for measurements and images and analysed craniodental and postcranial elements. This assemblage has been determined to be of a medium-sized hipparion with an elongated muzzle, well developed preorbital fossa that is dorsoventrally extensive and placed close to the orbit, lacking a caninus fossa and having a prominent and deep buccinator fossa. As such, this assemblage is referable to Cremohipparion moldavicum Gromova 1952 common to the Western Ukraine, Balkans, Romania, Republic of Georgia, Turkey and Iran. We have employed a combination of gross cheek tooth wear morphology utilizing the mesowear method and a microscopic analysis of occlusal enamel scars utilizin...
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