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Alexander S. Graphodatsky - One of the best experts on this subject based on the ideXlab platform.
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Comparative chromosome painting of pronghorn (Antilocapra americana) and saola (Pseudoryx nghetinhensis) karyotypes with human and dromedary camel probes
BMC Genetics, 2014Co-Authors: Anastasia I. Kulemzina, Polina L. Perelman, Darya A Grafodatskaya, Trung T Nguyen, Mary Thompson, Melody E Roelke-parker, Alexander S. GraphodatskyAbstract:Background Pronghorn (Antilocapridae, 2n = 58) and saola (Bovidae, 2n = 50) are members of Pecora, a highly diversified group of even-toed hoofed mammals. Karyotypes of these species were not involved in chromosome painting studies despite their intriguing phylogenetic positions in Pecora. Results To trace the chromosome evolution during very fast radiation of main families from the common Pecoran ancestor, high-resolution comparative chromosome maps of pronghorn and saola with human (HSA) and dromedary camel (CDR) painting probes were established. The human and dromedary camel painting probes revealed 50 and 64 conserved segments respectively in the pronghorn genome, while 51 and 63 conserved segments respectively in the saola genome. Integrative analysis with published comparative maps showed that inversions in chromosomes homologous to CDR19/35/19 (HSA 10/20/10), CDR12/34/12 (HSA12/22/12/22), CDR10/33/10 (HSA 11) are present in representatives of all five living Pecoran families. The pronghorn karyotype could have formed from a putative 2n = 58 Pecoran ancestral karyotype by one fission and one fusion and that the saola karyotype differs from the presumed 2n = 60 bovid ancestral karyotype (2n = 60) by five fusions. Conclusion The establishment of high-resolution comparative maps for pronghorn and saola has shed some new insights into the putative ancestral karyotype, chromosomal evolution and phylogenic relationships in Pecora. No cytogenetic signature rearrangements were found that could unite the Antilocapridae with Giraffidae or with any other Pecoran families. Our data on the saola support a separate position of Pseudorigyna subtribe rather than its affinity to either Bovina or Bubalina, but the saola phylogenetic position within Bovidae remains unresolved.
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Molecular cytogenetic insights to the phylogenetic affinities of the giraffe (Giraffa camelopardalis) and pronghorn (Antilocapra americana)
Chromosome Research, 2013Co-Authors: Halina Cernohorska, Svatava Kubickova, Olga Kopecna, Anastasia I. Kulemzina, Polina L. Perelman, Frederick F. B. Elder, Terence J. Robinson, Alexander S. Graphodatsky, Jiri RubesAbstract:Five families are traditionally recognized within higher ruminants (Pecora): Bovidae, Moschidae, Cervidae, Giraffidae and Antilocapridae. The phylogenetic relationships of Antilocapridae and Giraffidae within Pecora are, however, uncertain. While numerous fusions (mostly Robertsonian) have accumulated in the giraffe’s karyotype ( Giraffa camelopardalis , Giraffidae, 2 n = 30), that of the pronghorn ( Antilocapra americana , Antilocapridae, 2 n = 58) is very similar to the hypothesised pecoran ancestral state (2 n = 58). We examined the chromosomal rearrangements of two species, the giraffe and pronghorn, using a combination of fluorescence in situ hybridization painting probes and BAC clones derived from cattle ( Bos taurus , Bovidae). Our data place Moschus (Moschidae) closer to Bovidae than Cervidae. Although the alternative (i.e., Moschidae + Cervidae as sister groups) could not be discounted in recent sequence-based analyses, cytogenetics bolsters conclusions that the former is more likely. Additionally, DNA sequences were isolated from the centromeric regions of both species and compared. Analysis of cenDNA show that unlike the pronghorn, the centromeres of the giraffe are probably organized in a more complex fashion comprising different repetitive sequences specific to single chromosomal pairs or groups of chromosomes. The distribution of nucleolar organiser region (NOR) sites, often an effective phylogenetic marker, were also examined in the two species. In the giraffe, the position of NORs seems to be autapomorphic since similar localizations have not been found in other species within Pecora.
Florent Rivals - One of the best experts on this subject based on the ideXlab platform.
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The Role of Grass vs. Exogenous Abrasives in the Paleodietary Patterns of North American Ungulates
Frontiers in Ecology and Evolution, 2019Co-Authors: Gina M Semprebon, Florent Rivals, Christine M. JanisAbstract:The attainment of high crowned teeth (hypsodonty) has often been thought to be associated with grazing because many abrasive opal particles are known in grass that are presumed to wear down mammalian teeth. Equids have often been discussed regarding tooth morphological change due to the evolution of highly hypsodont teeth over time, the hyper-grazing habits of modern horses, and the originally-held view that the acquisition of hypsodonty and the widespread appearance of grasslands were synchronous. Recent studies, however, have reported asynchrony in the origin of hypsodonty and the widespread appearance of grasslands and have considered exposure to exogenous grit as important evolutionary drivers of hypsodonty in ungulates. We tracked changes in crown height (hypsodonty index), relative abrasion (mesowear) and food and grit scar topography on dental enamel (microwear) to examine the relative contributions of grass versus grit as a driving force in ungulate tooth changes during the evolution of North American Equidae compared to four North American ruminant artiodactyl families (Camelidae, Antilocapridae, Dromomerycidae, and Merycoidodontidae). We found that the overall pattern of the timing of the attainment of hypsodonty is inconsistent with grazing as the main impetus for the “Great Transition” within equids nor within the artiodactyl families as highly hypsodont ungulates post-date the spread of widespread grasslands. Mesowear closely mirrored hypsodonty trends in all families. Microwear patterns, particularly high degrees of enamel pitting (particularly large pits) and unusually coarse scratch textures in all five families, are consistent with exposure to exogenous grit as the main driver of hypsodonty acquisition prior to the consumption of significant levels of grass. Equidae exhibited a wider array of dietary behavior than the other families through most of their evolutionary history. Even so, grass was a much more common dietary item for equids than for the other families, and when combined with exogenous grit, which was more accelerated from the early Miocene onward based on more pitting and coarser scratch textures, may explain the more extreme acquisition of hypsodonty in equids compared to the artiodactyl families studied and set the stage for the Equidae alone to become hypergrazers in the Recent.
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was grass more prevalent in the pronghorn past an assessment of the dietary adaptations of miocene to recent Antilocapridae mammalia artiodactyla
Palaeogeography Palaeoclimatology Palaeoecology, 2007Co-Authors: Gina M Semprebon, Florent RivalsAbstract:Abstract Molar teeth of both Tertiary and Quaternary representatives of the family Antilocapridae were examined using mesowear and light stereomicroscopy microwear. Taxa from the Central and Southern Great Plains and the Northern and Southern Great Basin were included in the analyses and results compared to those obtained on the modern pronghorn ( Antilocapra americana ). Species included spanned from the early Miocene (late Hemingfordian) to the late Pleistocene (Rancholabrean). Results are concordant with well-known trends toward increasing aridity and shifts in vegetational structure in the late Miocene–early Pliocene of North America. Both mesowear and microwear results indicate a shift toward more abrasive diets beginning in the Hemphillian (late Miocene–Pliocene) and then a return to a less abrasive dietary regime for the duration of the Pleistocene and into the Recent. The more derived antilocaprines (more hypsodont, relatively longer limbs) apparently depended more on grass than the less advanced merycodontines, but even the earliest of the latter seem to have relied more on grass as a dietary staple than the modern pronghorn. Seasonal grit encroachment on food items encountered by fossil antilocaprids coupled with a heavier reliance on grasses may provide a possible explanation for the extreme hypsodonty present in the modern pronghorn despite its mainly browsing dietary behavior.
Anastasia I. Kulemzina - One of the best experts on this subject based on the ideXlab platform.
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X chromosome evolution in cetartiodactyla
Genes, 2017Co-Authors: Anastasia A. Proskuryakova, Anastasia I. Kulemzina, Polina L. Perelman, Alexey I. Makunin, Denis M. Larkin, Marta Farré, Anna V. Kukekova, Jennifer L. Johnson, Natalya A. Lemskaya, Violetta R. BeklemishevaAbstract:The phenomenon of a remarkable conservation of the X chromosome in eutherian mammals has been first described by Susumu Ohno in 1964. A notable exception is the cetartiodactyl X chromosome, which varies widely in morphology and G-banding pattern between species. It is hypothesized that this sex chromosome has undergone multiple rearrangements that changed the centromere position and the order of syntenic segments over the last 80 million years of Cetartiodactyla speciation. To investigate its evolution we have selected 26 evolutionarily conserved bacterial artificial chromosome (BAC) clones from the cattle CHORI-240 library evenly distributed along the cattle X chromosome. High-resolution BAC maps of the X chromosome on a representative range of cetartiodactyl species from different branches: pig (Suidae), alpaca (Camelidae), gray whale (Cetacea), hippopotamus (Hippopotamidae), Java mouse-deer (Tragulidae), pronghorn (Antilocapridae), Siberian musk deer (Moschidae), and giraffe (Giraffidae) were obtained by fluorescent in situ hybridization. To trace the X chromosome evolution during fast radiation in specious families, we performed mapping in several cervids (moose, Siberian roe deer, fallow deer, and Pere David’s deer) and bovid (muskox, goat, sheep, sable antelope, and cattle) species. We have identified three major conserved synteny blocks and rearrangements in different cetartiodactyl lineages and found that the recently described phenomenon of the evolutionary new centromere emergence has taken place in the X chromosome evolution of Cetartiodactyla at least five times. We propose the structure of the putative ancestral cetartiodactyl X chromosome by reconstructing the order of syntenic segments and centromere position for key groups.
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Comparative chromosome painting of pronghorn (Antilocapra americana) and saola (Pseudoryx nghetinhensis) karyotypes with human and dromedary camel probes
BMC Genetics, 2014Co-Authors: Anastasia I. Kulemzina, Polina L. Perelman, Darya A Grafodatskaya, Trung T Nguyen, Mary Thompson, Melody E Roelke-parker, Alexander S. GraphodatskyAbstract:Background Pronghorn (Antilocapridae, 2n = 58) and saola (Bovidae, 2n = 50) are members of Pecora, a highly diversified group of even-toed hoofed mammals. Karyotypes of these species were not involved in chromosome painting studies despite their intriguing phylogenetic positions in Pecora. Results To trace the chromosome evolution during very fast radiation of main families from the common Pecoran ancestor, high-resolution comparative chromosome maps of pronghorn and saola with human (HSA) and dromedary camel (CDR) painting probes were established. The human and dromedary camel painting probes revealed 50 and 64 conserved segments respectively in the pronghorn genome, while 51 and 63 conserved segments respectively in the saola genome. Integrative analysis with published comparative maps showed that inversions in chromosomes homologous to CDR19/35/19 (HSA 10/20/10), CDR12/34/12 (HSA12/22/12/22), CDR10/33/10 (HSA 11) are present in representatives of all five living Pecoran families. The pronghorn karyotype could have formed from a putative 2n = 58 Pecoran ancestral karyotype by one fission and one fusion and that the saola karyotype differs from the presumed 2n = 60 bovid ancestral karyotype (2n = 60) by five fusions. Conclusion The establishment of high-resolution comparative maps for pronghorn and saola has shed some new insights into the putative ancestral karyotype, chromosomal evolution and phylogenic relationships in Pecora. No cytogenetic signature rearrangements were found that could unite the Antilocapridae with Giraffidae or with any other Pecoran families. Our data on the saola support a separate position of Pseudorigyna subtribe rather than its affinity to either Bovina or Bubalina, but the saola phylogenetic position within Bovidae remains unresolved.
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Molecular cytogenetic insights to the phylogenetic affinities of the giraffe (Giraffa camelopardalis) and pronghorn (Antilocapra americana)
Chromosome Research, 2013Co-Authors: Halina Cernohorska, Svatava Kubickova, Olga Kopecna, Anastasia I. Kulemzina, Polina L. Perelman, Frederick F. B. Elder, Terence J. Robinson, Alexander S. Graphodatsky, Jiri RubesAbstract:Five families are traditionally recognized within higher ruminants (Pecora): Bovidae, Moschidae, Cervidae, Giraffidae and Antilocapridae. The phylogenetic relationships of Antilocapridae and Giraffidae within Pecora are, however, uncertain. While numerous fusions (mostly Robertsonian) have accumulated in the giraffe’s karyotype ( Giraffa camelopardalis , Giraffidae, 2 n = 30), that of the pronghorn ( Antilocapra americana , Antilocapridae, 2 n = 58) is very similar to the hypothesised pecoran ancestral state (2 n = 58). We examined the chromosomal rearrangements of two species, the giraffe and pronghorn, using a combination of fluorescence in situ hybridization painting probes and BAC clones derived from cattle ( Bos taurus , Bovidae). Our data place Moschus (Moschidae) closer to Bovidae than Cervidae. Although the alternative (i.e., Moschidae + Cervidae as sister groups) could not be discounted in recent sequence-based analyses, cytogenetics bolsters conclusions that the former is more likely. Additionally, DNA sequences were isolated from the centromeric regions of both species and compared. Analysis of cenDNA show that unlike the pronghorn, the centromeres of the giraffe are probably organized in a more complex fashion comprising different repetitive sequences specific to single chromosomal pairs or groups of chromosomes. The distribution of nucleolar organiser region (NOR) sites, often an effective phylogenetic marker, were also examined in the two species. In the giraffe, the position of NORs seems to be autapomorphic since similar localizations have not been found in other species within Pecora.
Gina M Semprebon - One of the best experts on this subject based on the ideXlab platform.
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The Role of Grass vs. Exogenous Abrasives in the Paleodietary Patterns of North American Ungulates
Frontiers in Ecology and Evolution, 2019Co-Authors: Gina M Semprebon, Florent Rivals, Christine M. JanisAbstract:The attainment of high crowned teeth (hypsodonty) has often been thought to be associated with grazing because many abrasive opal particles are known in grass that are presumed to wear down mammalian teeth. Equids have often been discussed regarding tooth morphological change due to the evolution of highly hypsodont teeth over time, the hyper-grazing habits of modern horses, and the originally-held view that the acquisition of hypsodonty and the widespread appearance of grasslands were synchronous. Recent studies, however, have reported asynchrony in the origin of hypsodonty and the widespread appearance of grasslands and have considered exposure to exogenous grit as important evolutionary drivers of hypsodonty in ungulates. We tracked changes in crown height (hypsodonty index), relative abrasion (mesowear) and food and grit scar topography on dental enamel (microwear) to examine the relative contributions of grass versus grit as a driving force in ungulate tooth changes during the evolution of North American Equidae compared to four North American ruminant artiodactyl families (Camelidae, Antilocapridae, Dromomerycidae, and Merycoidodontidae). We found that the overall pattern of the timing of the attainment of hypsodonty is inconsistent with grazing as the main impetus for the “Great Transition” within equids nor within the artiodactyl families as highly hypsodont ungulates post-date the spread of widespread grasslands. Mesowear closely mirrored hypsodonty trends in all families. Microwear patterns, particularly high degrees of enamel pitting (particularly large pits) and unusually coarse scratch textures in all five families, are consistent with exposure to exogenous grit as the main driver of hypsodonty acquisition prior to the consumption of significant levels of grass. Equidae exhibited a wider array of dietary behavior than the other families through most of their evolutionary history. Even so, grass was a much more common dietary item for equids than for the other families, and when combined with exogenous grit, which was more accelerated from the early Miocene onward based on more pitting and coarser scratch textures, may explain the more extreme acquisition of hypsodonty in equids compared to the artiodactyl families studied and set the stage for the Equidae alone to become hypergrazers in the Recent.
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was grass more prevalent in the pronghorn past an assessment of the dietary adaptations of miocene to recent Antilocapridae mammalia artiodactyla
Palaeogeography Palaeoclimatology Palaeoecology, 2007Co-Authors: Gina M Semprebon, Florent RivalsAbstract:Abstract Molar teeth of both Tertiary and Quaternary representatives of the family Antilocapridae were examined using mesowear and light stereomicroscopy microwear. Taxa from the Central and Southern Great Plains and the Northern and Southern Great Basin were included in the analyses and results compared to those obtained on the modern pronghorn ( Antilocapra americana ). Species included spanned from the early Miocene (late Hemingfordian) to the late Pleistocene (Rancholabrean). Results are concordant with well-known trends toward increasing aridity and shifts in vegetational structure in the late Miocene–early Pliocene of North America. Both mesowear and microwear results indicate a shift toward more abrasive diets beginning in the Hemphillian (late Miocene–Pliocene) and then a return to a less abrasive dietary regime for the duration of the Pleistocene and into the Recent. The more derived antilocaprines (more hypsodont, relatively longer limbs) apparently depended more on grass than the less advanced merycodontines, but even the earliest of the latter seem to have relied more on grass as a dietary staple than the modern pronghorn. Seasonal grit encroachment on food items encountered by fossil antilocaprids coupled with a heavier reliance on grasses may provide a possible explanation for the extreme hypsodonty present in the modern pronghorn despite its mainly browsing dietary behavior.
F B P Wooding - One of the best experts on this subject based on the ideXlab platform.
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glycosylation and immunocytochemistry of binucleate cells in pronghorn antilocapra americana Antilocapridae show features of both giraffidae and bovidae
Placenta, 2017Co-Authors: Carolyn J P Jones, W J Silvia, C H Hamilton, T W Geary, A L Zezeski, F B P WoodingAbstract:Abstract Although the pronghorn ( Antilocapra americana ) resembles an antelope, its nearest relatives are the giraffe and okapi. In this study we have examined the placentae of 6 pronghorns using lectin- and immunocytochemistry to identify giraffid and bovid features. Binucleate cells (BNC) of the placenta exhibited features intermediate between those of the giraffe and bovine; Dolichos biflorus agglutinin binding – strong in the bovine BNC and absent in the giraffe – was evident in only a subpopulation of BNC while binding to blood vessels, as in the giraffe. Binding of Phytolacca americana agglutinin resembled that of the giraffe and okapi whereas many other glycans were found in all four clades. PAG antigens were similar to bovine and okapi but not giraffe. In summary, although the pronghorn outwardly resembles an antelope, placental BNC show giraffid features. Although each clade has its own individual characteristics, there are far more similarities than differences between them, emphasizing the common ancestry of all four clades.