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1.
J Hum Evol ; 185: 103452, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37935595

RESUMO

Ekgmowechashala is a poorly documented but very distinctive primate known only from the late early Oligocene (early Arikareean) of western North America. Because of its highly autapomorphous dentition and spatiotemporal isolation, the phylogenetic and biogeographic affinities of Ekgmowechashala have long been debated. Here, we describe the oldest known fossils of Ekgmowechashala from the Brown Siltstone Beds of the Brule Formation, White River Group of western Nebraska. We also describe a new ekgmowechashaline taxon from the Nadu Formation (late Eocene) in the Baise Basin of Guangxi Zhuang Autonomous Region in southern China. Phylogenetic analysis suggests that North American Ekgmowechashala and the new Chinese taxon are sister taxa that are nested within a radiation of southern Asian adapiforms that also includes Gatanthropus, Muangthanhinius, and Bugtilemur. The new Chinese ekgmowechashaline helps fill the considerable disparity in dental morphology between Ekgmowechashala and more primitive ekgmowechashalids known from southern Asia. Our study underscores the fundamental role of southern Asia as a refugium for multiple primate clades during the cooler and drier climatic regime that prevailed after the Eocene-Oligocene transition. The colonization of North America by Ekgmowechashala helps define the beginning of the Arikareean Land Mammal Age and corresponds to an example of the Lazarus effect, whereby a taxon (in this case, the order Primates) reappears suddenly in the fossil record after a lengthy hiatus.


Assuntos
Fósseis , Primatas , Animais , Filogenia , China , Nebraska , Primatas/anatomia & histologia , América do Norte , Mamíferos
2.
J Hum Evol ; 181: 103395, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37320961

RESUMO

The morphological adaptations of euprimates have been linked to their origin and early evolution in an arboreal environment. However, the ancestral and early locomotor repertoire of this group remains contentious. Although some tarsal bones like the astragalus and the calcaneus have been thoroughly studied, the navicular remains poorly studied despite its potential implications for foot mobility. Here, we evaluate early euprimate locomotion by assessing the shape of the navicular-an important component of the midtarsal region of the foot-using three-dimensional geometric morphometrics in relation to quantified locomotor repertoire in a wide data set of extant primates. We also reconstruct the locomotor repertoire of representatives of the major early primate lineages with a novel phylogenetically informed discriminant analysis and characterize the changes that occurred in the navicular during the archaic primate-euprimate transition. To do so, we included in our study an extensive sample of naviculars (36 specimens) belonging to different species of adapiforms, omomyiforms, and plesiadapiforms. Our results indicate that navicular shape embeds a strong functional signal, allowing us to infer the type of locomotion of extinct primates. We demonstrate that early euprimates displayed a diverse locomotor behavior, although they did not reach the level of specialization of some living forms. Finally, we show that the navicular bone experienced substantial reorganization throughout the archaic primate-euprimate transition, supporting the major functional role of the tarsus during early primate evolution. This study demonstrates that navicular shape can be used as a reliable proxy for primate locomotor behavior. In addition, it sheds light on the diverse locomotor behavior of early primates as well as on the archaic primate-euprimate transition, which involved profound morphological changes within the tarsus, including the navicular bone.


Assuntos
Evolução Biológica , Tálus , Animais , Fósseis , Tálus/anatomia & histologia , Primatas/anatomia & histologia , Pé/anatomia & histologia , Locomoção
3.
Science ; 380(6648): 913-924, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-37262173

RESUMO

Comparative analysis of primate genomes within a phylogenetic context is essential for understanding the evolution of human genetic architecture and primate diversity. We present such a study of 50 primate species spanning 38 genera and 14 families, including 27 genomes first reported here, with many from previously less well represented groups, the New World monkeys and the Strepsirrhini. Our analyses reveal heterogeneous rates of genomic rearrangement and gene evolution across primate lineages. Thousands of genes under positive selection in different lineages play roles in the nervous, skeletal, and digestive systems and may have contributed to primate innovations and adaptations. Our study reveals that many key genomic innovations occurred in the Simiiformes ancestral node and may have had an impact on the adaptive radiation of the Simiiformes and human evolution.


Assuntos
Evolução Molecular , Primatas , Animais , Humanos , Genoma , Genômica , Filogenia , Primatas/anatomia & histologia , Primatas/classificação , Primatas/genética , Rearranjo Gênico , Encéfalo/anatomia & histologia
4.
Neuroimage ; 273: 120096, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37031828

RESUMO

A comparison of neuroanatomical features of the brain between humans and our evolutionary relatives, nonhuman primates, is key to understanding the human brain system and the neural basis of mental and neurological disorders. Although most comparative MRI studies of human and nonhuman primate brains have been based on brains of primates that had been used as subjects in experiments, it is essential to investigate various species of nonhuman primates in order to elucidate and interpret the diversity of neuroanatomy features among humans and nonhuman primates. To develop a research platform for this purpose, it is necessary to harmonize the scientific contributions of studies with the standards of animal ethics, animal welfare, and the conservation of brain information for long-term continuation of the field. In previous research, we first developed a gated data-repository of anatomical images obtained using 9.4-T ex vivo MRI of postmortem brain samples from 12 nonhuman primate species, and which are stored at the Japan Monkey Centre. In the present study, as a second phase, we released a collection of T2-weighted images and diffusion tensor images obtained in nine species: white-throated capuchin, Bolivian squirrel monkey, stump-tailed macaque, Tibet monkey, Sykes' monkey, Assamese macaque, pig-tailed macaque, crested macaque, and chimpanzee. Our image repository should facilitate scientific discoveries in the field of comparative neuroscience. This repository can also promote animal ethics and animal welfare in experiments with nonhuman primate models by optimizing methods for in vivo and ex vivo MRI scanning of brains and supporting veterinary neuroradiological education. In addition, the repository is expected to contribute to conservation, preserving information about the brains of various primates, including endangered species, in a permanent digital form.


Assuntos
Imageamento por Ressonância Magnética , Primatas , Animais , Humanos , Japão , Primatas/anatomia & histologia , Encéfalo/diagnóstico por imagem , Encéfalo/anatomia & histologia , Macaca , Espectroscopia de Ressonância Magnética , Neuroimagem
5.
Anat Rec (Hoboken) ; 306(11): 2853-2871, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-36897245

RESUMO

The placental order Dermoptera, which includes two extant species, the Philippine and Sunda flying lemurs, Cynocephalus volans and Galeopterus variegatus, respectively, is generally held to be the sister group of Primates. Yet, little has been reported on their cranial anatomy. Here, the anatomy of the ear region is described and illustrated for a juvenile and adult C. volans based on CT scans. The inclusion of a juvenile is essential as nearly all cranial sutures are fused in the adult. Soft tissues are reconstructed based on sectioned histological pre- and postnatal specimens previously reported by the author. Numerous unusual features are identified, including: a small parasphenoid beneath the basisphenoid, a tensor tympani fossa on the epitympanic wing of the squamosal, a cavum supracochleare for the geniculate ganglion of the facial nerve that is not enclosed in the petrosal bone, a secondary facial foramen between the petrosal and squamosal, a secondary posttemporal foramen leading to the primary one, a subarcuate fossa that is floored in part by a large contribution from the squamosal, a body of the incus larger than the head of the malleus, and a crus longum of the incus that lacks an osseous connection to the lenticular process. Documentation of the anatomy of the Philippine flying lemur ear region is an essential first step in morphological phylogenetic analyses where features of the basicranium are widely sampled.


Assuntos
Quirópteros , Lemur , Gravidez , Animais , Feminino , Filogenia , Lemur/anatomia & histologia , Filipinas , Placenta , Primatas/anatomia & histologia
6.
Evolution ; 76(12): 3071-3072, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36097360

RESUMO

The availability of genome sequences from large numbers of species offers the prospect of studying genotype-phenotype correlations across various phylogenetic scales using only available data. A new study illustrates the power of this approach, showing an association across primates between morphological sexual dimorphism and the prevalence of a class of DNA elements that stimulate gene expression in response to male androgens.


Assuntos
Genoma , Seleção Sexual , Animais , Masculino , Filogenia , Primatas/genética , Primatas/anatomia & histologia , Caracteres Sexuais , Genômica
7.
Proc Natl Acad Sci U S A ; 119(35): e2123366119, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-35994633

RESUMO

Variability in resource availability is hypothesized to be a significant driver of primate adaptation and evolution, but most paleoclimate proxies cannot recover environmental seasonality on the scale of an individual lifespan. Oxygen isotope compositions (δ18O values) sampled at high spatial resolution in the dentitions of modern African primates (n = 2,352 near weekly measurements from 26 teeth) track concurrent seasonal precipitation, regional climatic patterns, discrete meteorological events, and niche partitioning. We leverage these data to contextualize the first δ18O values of two 17 Ma Afropithecus turkanensis individuals from Kalodirr, Kenya, from which we infer variably bimodal wet seasons, supported by rainfall reconstructions in a global Earth system model. Afropithecus' δ18O fluctuations are intermediate in magnitude between those measured at high resolution in baboons (Papio spp.) living across a gradient of aridity and modern forest-dwelling chimpanzees (Pan troglodytes verus). This large-bodied Miocene ape consumed seasonally variable food and water sources enriched in 18O compared to contemporaneous terrestrial fauna (n = 66 fossil specimens). Reliance on fallback foods during documented dry seasons potentially contributed to novel dental features long considered adaptations to hard-object feeding. Developmentally informed microsampling recovers greater ecological complexity than conventional isotope sampling; the two Miocene apes (n = 248 near weekly measurements) evince as great a range of seasonal δ18O variation as more time-averaged bulk measurements from 101 eastern African Plio-Pleistocene hominins and 42 papionins spanning 4 million y. These results reveal unprecedented environmental histories in primate teeth and suggest a framework for evaluating climate change and primate paleoecology throughout the Cenozoic.


Assuntos
Evolução Biológica , Mudança Climática , Fósseis , Isótopos de Oxigênio , Pan troglodytes , Dente , África , Animais , Guiné Equatorial , Fósseis/anatomia & histologia , História do Século XXI , Hominidae/anatomia & histologia , Quênia , Isótopos de Oxigênio/análise , Pan troglodytes/anatomia & histologia , Papio/anatomia & histologia , Primatas/anatomia & histologia , Dente/anatomia & histologia , Dente/química
8.
PLoS One ; 17(6): e0269041, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35666739

RESUMO

The evolution of the remarkably complex primate brain has been a topic of great interest for decades. Multiple factors have been proposed to explain the comparatively larger primate brain (relative to body mass), with recent studies indicating diet has the greatest explanatory power. Dietary specialisations also correlate with dental adaptations, providing a potential evolutionary link between brain and dental morphological evolution. However, unambiguous evidence of association between brain and dental phenotypes in primates remains elusive. Here we investigate the effect of diet on variation in primate brain and dental morphology and test whether the two anatomical systems coevolved. We focused on the primate suborder Strepsirrhini, a living primate group that occupies a very wide range of dietary niches. By making use of both geometric morphometrics and dental topographic analysis, we extend the study of brain-dental ecomorphological evolution beyond measures of size. After controlling for allometry and evolutionary relatedness, differences in brain and dental morphology were found between dietary groups, and brain and dental morphologies were found to covary. Historical trajectories of morphological diversification revealed a strong integration in the rates of brain and dental evolution and similarities in their modes of evolution. Combined, our results reveal an interplay between brain and dental ecomorphological adaptations throughout strepsirrhine evolution that can be linked to diet.


Assuntos
Primatas , Strepsirhini , Animais , Evolução Biológica , Encéfalo , Dieta , Filogenia , Primatas/anatomia & histologia , Strepsirhini/anatomia & histologia
9.
J Hum Evol ; 169: 103221, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35772227

RESUMO

Within the primate order, the morphology of the shoulder girdle is immensely variable and has been shown to reflect the functional demands of the upper limb. The observed morphological variation among extant primate taxa consequently has been hypothesized to be driven by selection for different functional demands. Evolutionary analyses of the shoulder girdle often assess this anatomical region, and its traits, individually, therefore implicitly assuming independent evolution of the shoulder girdle. However, the primate shoulder girdle has developmental and functional covariances with the basicranium and pelvic girdle that have been shown to potentially influence its evolution. It is unknown whether these relationships are similar or even present across primate taxa, and how they may affect morphological variation among primates. This study evaluates the strength of covariance and evolutionary potential across four anatomical regions: shoulder girdle, basicranium, pelvis, and distal humerus. Measures of morphological integration and evolutionary potential (conditioned covariance and evolutionary flexibility) are assessed across eight anthropoid primate taxa. Results demonstrate a consistent pattern of morphological constraint within paired anatomical regions across primates. Differences in evolutionary flexibility are observed among primate genera, with humans having the highest evolutionary potential overall. This pattern does not follow functional differences, but rather a separation between monkeys and apes. Therefore, evolutionary hypotheses of primate shoulder girdle morphological variation that evaluate functional demands alone may not account for the effect of these relationships. Collectively, our findings suggest differences in genetic covariance among anatomical regions may have contributed to the observable morphological variation among taxa.


Assuntos
Hominidae , Ombro , Animais , Braço , Evolução Biológica , Hominidae/anatomia & histologia , Humanos , Pelve , Primatas/anatomia & histologia , Primatas/genética , Ombro/anatomia & histologia , Base do Crânio/anatomia & histologia
10.
J Hum Evol ; 166: 103177, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35390563

RESUMO

The morphological affinities of a primate proximal ulna (KNM-WS 65401) recovered from the late Early Miocene site Buluk, Kenya, are appraised. Nineteen three-dimensional landmarks on ulnae from 36 extant anthropoid species (n = 152 individuals) and KNM-WS 65401, as well as a subset of 14 landmarks on six ulnae belonging to other East African Miocene catarrhine taxa, were collected. To quantify ulnar shape, three-dimensional geometric morphometric techniques were used and linear dimensions commonly cited in the literature were derived from the landmark data. KNM-WS 65401 is situated between monkeys and hominoids in the principal components morphospace. KNM-WS 65401 shares features such as a short olecranon process, broad trochlear notch, and laterally oriented radial notch with extant hominoids, whereas features such as an anteriorly directed trochlear notch and flat, proximodistally elongated, and anteroposteriorly narrow radial notch are shared with extant monkeys. Principal component scores and linear metrics generally align KNM-WS 65401 with both suspensors and arboreal quadrupeds, but quadratic and linear discriminant analyses of principal component score data provide posterior probabilities of 80% and 83%, respectively, for assignment of KNM-WS 65401 to the suspensory group. Compared with fossil ulnae from other Miocene primates, KNM-WS 65401 is morphologically most distinct from KNM-LG 6, attributed to Dendropithecus macinnesi, and morphologically most similar to KNM-WK 16950R, attributed to Turkanapithecus kalakolensis. The KNM-WS 65401 individual likely possessed more enhanced capabilities for elbow joint extension, perhaps during suspensory behaviors, compared with other Miocene primates in the sample.


Assuntos
Fósseis , Hominidae , Animais , Hominidae/anatomia & histologia , Quênia , Primatas/anatomia & histologia , Ulna/anatomia & histologia
11.
Anat Rec (Hoboken) ; 305(9): 2227-2248, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35133075

RESUMO

The temporomandibular joint is the direct interface between the mandible and the cranium and is critical for transmitting joint reaction forces and determining mandibular range of motion. As a consequence, understanding variation in the morphology of this joint and how it relates to other aspects of craniofacial form is important for better understanding masticatory function. Here, we present a detailed three-dimensional (3D) geometric morphometric analysis of the cranial component of this joint, the glenoid fossa, across a sample of 17 anthropoid primates, and we evaluate covariation between the glenoid and the cranium and mandible. We find high levels of intraspecific variation in glenoid shape that is likely linked to sexual dimorphism and joint remodeling, and we identify differences in mean glenoid shape across taxonomic groups and in relation to size. Analyses of covariation reveal strong relationships between glenoid shape and a variety of aspects of cranial and mandibular form. Our findings suggest that intraspecific variation in glenoid shape in primates could further be reflective of high levels of functional flexibility in the masticatory apparatus, as has also been suggested for primate jaw kinematics and muscle activation patterns. Conversely, interspecific differences likely reflect larger scale differences between species in body size and/or masticatory function. Results of the covariation analyses dovetail with those examining covariation in the cranium of canids and may be indicative of larger patterns across mammals.


Assuntos
Primatas , Articulação Temporomandibular , Animais , Haplorrinos , Mamíferos , Filogenia , Primatas/anatomia & histologia , Crânio/anatomia & histologia , Articulação Temporomandibular/anatomia & histologia
12.
J Hum Evol ; 164: 103141, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35158085

RESUMO

Early Eocene primate postcranial bones from the Vastan lignite mine of Gujarat, India, have proven useful for understanding the haplorhine and strepsirrhine divergence. Previous analyses of material assigned to Asiadapidae supported interpretations that these primates were generalized arboreal quadrupeds, while the omomyid Vastanomys was likely to have been more proficient leaper than asiadapids. More recent examinations of long bone cross-sectional properties and calcaneal elongation have complicated the behavioral interpretations of these fossils. This study examines whole talar and calcaneal morphology of the Vastan material to refine the locomotor reconstructions of these fossils. A comparative sample of extant primate species representing various locomotor behaviors was obtained by accessing surface models from MorphoSource.org. Surface models of fossil specimens attributed to Asiadapis cambayensis, Marcgodinotius indicus, and Vastanomys major were generated from micro-computed tomography scans. A morphological analysis was carried out using weighted spherical harmonics, a Fourier-based method that represents surfaces using coefficients associated with a common set of spherical harmonic functions. The coefficients describing each surface were then used as shape variables in a principal components analysis. Significant differences between locomotor groups were assessed using nonparametric tests. Results from extant comparative samples show that locomotor behavior can be predicted from both talar and calcaneal morphology when phylogenetic relationships are known. Consistent with previous analyses, our results indicate that Asiadapis cambayensis and Marcgodinotius indicus were likely arboreal quadrupeds with some leaping capabilities. Vastanomys major is reconstructed as an arboreal quadruped with greater leaping proficiency than its asiadapid counterparts based on its talar morphology.


Assuntos
Calcâneo , Fósseis , Animais , Calcâneo/anatomia & histologia , Filogenia , Primatas/anatomia & histologia , Microtomografia por Raio-X
13.
J Hum Evol ; 162: 103094, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34808474

RESUMO

The hyoid apparatus plays an integral role in swallowing, respiration, and vocalization in mammals. Most placental mammals have a rod-shaped basihyal connected to the basicranium via both soft tissues and a mobile bony chain-the anterior cornu-whereas anthropoid primates have broad, shield-like or even cup-shaped basihyals suspended from the basicranium by soft tissues only. How the unique anthropoid hyoid morphology evolved is unknown, and hyoid morphology of nonanthropoid primates is poorly documented. Here we use phylogenetic comparative methods and linear morphometrics to address knowledge gaps in hyoid evolution among primates and their euarchontan outgroups. We find that dermopterans have variable reduction of cornu elements. Cynocephalus volans are sexually dimorphic in hyoid morphology. Tupaia and all lemuroids except Daubentonia have a fully ossified anterior cornu connecting a rod-shaped basihyal to the basicranium; this is the ancestral mammalian pattern that is also characteristic of the last common ancestor of Primates. Haplorhines exhibit a reduced anterior cornu, and anthropoids underwent further increase in basihyal aspect ratio values and in relative basihyal volume. Convergent with haplorhines, lorisoid strepsirrhines independently evolved a broad basihyal and reduced anterior cornua. While a reduced anterior cornu is hypothesized to facilitate vocal tract lengthening and lower formant frequencies in some mammals, our results suggest vocalization adaptations alone are unlikely to drive the iterative reduction of anterior cornua within Primates. Our new data on euarchontan hyoid evolution provide an anatomical basis for further exploring the form-function relationships of the hyoid across different behaviors, including vocalization, chewing, and swallowing.


Assuntos
Placenta , Primatas , Animais , Feminino , Haplorrinos , Osso Hioide/anatomia & histologia , Filogenia , Gravidez , Primatas/anatomia & histologia
14.
PLoS One ; 16(12): e0261185, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34932586

RESUMO

Despite decades of research, much uncertainty remains regarding the selection pressures responsible for brain size variation. Whilst the influential social brain hypothesis once garnered extensive support, more recent studies have failed to find support for a link between brain size and sociality. Instead, it appears there is now substantial evidence suggesting ecology better predicts brain size in both primates and carnivores. Here, different models of brain evolution were tested, and the relative importance of social, ecological, and life-history traits were assessed on both overall encephalisation and specific brain regions. In primates, evidence is found for consistent associations between brain size and ecological factors, particularly diet; however, evidence was also found advocating sociality as a selection pressure driving brain size. In carnivores, evidence suggests ecological variables, most notably home range size, are influencing brain size; whereas, no support is found for the social brain hypothesis, perhaps reflecting the fact sociality appears to be limited to a select few taxa. Life-history associations reveal complex selection mechanisms to be counterbalancing the costs associated with expensive brain tissue through extended developmental periods, reduced fertility, and extended maximum lifespan. Future studies should give careful consideration of the methods chosen for measuring brain size, investigate both whole brain and specific brain regions where possible, and look to integrate multiple variables, thus fully capturing all of the potential factors influencing brain size.


Assuntos
Evolução Biológica , Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Carnívoros/fisiologia , Primatas/fisiologia , Animais , Carnívoros/anatomia & histologia , Longevidade , Tamanho do Órgão , Primatas/anatomia & histologia , Comportamento Social
15.
PLoS One ; 16(9): e0256309, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34469439

RESUMO

Studies about the anatomy of the New World Primates are scarce, mainly comparative neuroanatomy, then a morphological comparative analysis about the tropical Primates were performed and a effort was made for an Old World Primates and modern humans relationship for the obtained data; plus, comments about behavior e and allometry were performed to try link the high cognition and abilities of the Sapajus with the neuroanatomical results, however, despite the deep neuroanatomic data obtained, we do not found an intrinsic relation to explain that.


Assuntos
Anatomia Comparada/métodos , Encéfalo/anatomia & histologia , Neuroanatomia/métodos , Primatas/anatomia & histologia , Animais , Feminino , Masculino , Sapajus
16.
Science ; 372(6544)2021 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-34016754

RESUMO

Charles Darwin's The Descent of Man, published 150 years ago, laid the grounds for scientific studies into human origins and evolution. Three of his insights have been reinforced by modern science. The first is that we share many characteristics (genetic, developmental, physiological, morphological, cognitive, and psychological) with our closest relatives, the anthropoid apes. The second is that humans have a talent for high-level cooperation reinforced by morality and social norms. The third is that we have greatly expanded the social learning capacity that we see already in other primates. Darwin's emphasis on the role of culture deserves special attention because during an increasingly unstable Pleistocene environment, cultural accumulation allowed changes in life history; increased cognition; and the appearance of language, social norms, and institutions.


Assuntos
Evolução Biológica , Evolução Cultural , Evolução Social , Animais , Encéfalo/anatomia & histologia , Encéfalo/crescimento & desenvolvimento , Gorilla gorilla , Humanos , Tamanho do Órgão , Primatas/anatomia & histologia , Primatas/crescimento & desenvolvimento , Primatas/fisiologia , Normas Sociais
17.
Sci Rep ; 11(1): 11245, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34045627

RESUMO

Scientific literature concerning genital bones in primates consists of both ancient works (dating back to the nineteenth century) and more recent revisions/meta-analyses, which, however, are not always so detailed or exhaustive. Based on a thorough analysis, several conflicting data, inaccurate references, and questionable claims have emerged. We generated a binary matrix of genital bone occurrence data, considering only data at the species level, based on (1) a rigorous literature search protocol, (2) raw data (collected exclusively from primary literature), (3) an updated taxonomy (often tracing back to the species taxonomic history) and (4) new occurrence data from scanned genitals of fresh and museum specimens (using micro-computed tomography-micro-CT). Thanks to this methodological approach, we almost doubled available occurrence data so far, avoiding any arbitrary extension of generic data to conspecific species. This practice, in fact, has been recently responsible for an overestimation of the occurrence data, definitively flattening the interspecific variability. We performed the ancestral state reconstruction analysis of genital bone occurrence and results were mapped onto the most updated phylogeny of primates. As for baculum, we definitively demonstrated its simplesiomorphy for the entire order. As for baubellum, we interpreted all scattered absences as losses, actually proposing (for the first time) a simplesiomorphic state for the clitoral bone as well. The occurrence data obtained, while indirectly confirming the baculum/baubellum homology (i.e., for each baubellum a baculum was invariably present), could also directly demonstrate an intra-specific variability affecting ossa genitalia occurrence. With our results, we established a radically improved and updated database about the occurrence of genital bones in primates, available for further comparative analyses.


Assuntos
Genitália/anatomia & histologia , Primatas/anatomia & histologia , Animais , Evolução Biológica , Bases de Dados Factuais , Genitália/diagnóstico por imagem , Microtomografia por Raio-X
18.
Am J Phys Anthropol ; 175(1): 292-299, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33454959

RESUMO

OBJECTIVES: A tooth chip occurs when a hard object forcefully contacts the surface of the tooth, typically removing enamel from the occlusal edge. In this study, chipping patterns in extant primates were compared, and hard-object-feeding assessed alongside other factors (e.g., grit mastication and dental properties), to elucidate dietary and behavioral inferences in archeological and paleontological samples. MATERIALS AND METHODS: Thirteen species of extant primates were studied, including eight species within the Cercopithecidae, two within the Ceboidea, and three within the Hominoidea. Four additional species were also incorporated from the literature for some of the analyses. The severity (Grade 1-3), position (buccal, lingual, mesial, and distal) and number of tooth fractures were recorded for each specimen. RESULTS: Species considered hard-object-feeding specialists presented higher rates of chipping, with sakis, mandrills, sooty mangabeys and Raffles' banded langurs having high chipping rates (28.3%, 36.7%, 48.4%, and 34.7% of teeth, respectively). Species that seasonally eat harder foods had intermediate chipping frequencies (e.g., brown woolly monkeys: 18.5%), and those that less commonly consume hard food items had the lowest chipping frequencies (e.g., Kloss gibbon: 7.3%; chimpanzees: 4.4%). DISCUSSION: The results suggest hard food mastication influences differences in chipping prevalence among the species studied. Although Homo fossil samples show high rates of chipping comparable to hard-object-feeding extant primates, they display a different pattern of chipping, supporting the hypothesis that these fractures are mostly non-food related (e.g., grit mastication in Homo naledi; non-masticatory tooth use in Neanderthals).


Assuntos
Dieta , Primatas/anatomia & histologia , Fraturas dos Dentes , Dente/patologia , Animais , Antropologia Física , Esmalte Dentário/patologia , Fósseis , Prevalência , Fraturas dos Dentes/epidemiologia , Fraturas dos Dentes/patologia , Fraturas dos Dentes/veterinária
19.
Am J Phys Anthropol ; 174(4): 728-743, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33483945

RESUMO

OBJECTIVES: The Willwood Formation of the southern Bighorn Basin, Wyoming is a fluvial rock sequence that spans approximately 3 million years of early Eocene time. It has yielded one the largest collections of fossil mammals in the world including thousands of dentitions of extinct lemur-like primates known as notharctines. In the southern Bighorn Basin, specimens of these primates have been collected on numerous paleontological expeditions and the stratigraphic levels yielding the dentitions have been carefully recorded. Notharctine dentitions represent a rare opportunity to study morphological variation in a single anatomical system through time among closely related individuals. MATERIALS AND METHODS: Prior studies of Bighorn Basin notharctines through time produced measurements of hundreds of specimens but I report here results from measurement and comparison of the dentitions and dentaries of more than 3,000 specimens, all stratigraphically mapped. RESULTS: Variation in premolar and molar area and variation in dentary depth are apparent throughout the section. Specimens with relatively small teeth and dentaries are known from the older part of the section. In younger rocks, variation in tooth area among specimens increases. Variation in tooth area is continuous and overlaps extensively both within and between stratigraphic levels. Other dental variables examined by inspection change in a mosaic and continuous fashion through the section. These features include variation in the presence and number of paraconids on the lower fourth premolar (p4), the size and shape of the entoconid notch on the lower first and second molars, and the relative development of the pseudohypocone, mesostyle, and cingula on the upper molars. DISCUSSION: These broad patterns can be identified despite notharctine alpha taxonomy being in need of extensive revision and, importantly, simplification. Such revision is beyond the scope of this article but is essential if we are to develop a taxonomy that is both free of stratigraphic influence and useful for rapid, repeatable species assignment. Boundaries among the patterns of tokogenesis, anagenesis, and cladogenesis are blurred in this dense sample of extinct primates. While pattern of evolution, a population-level phenomenon, may be difficult to falsify in the fossil record, this notharctine sample suggests that in the rare instance such as this, when the fossil record is densely sampled, change through time is continuous and more consistent with gradual evolution.


Assuntos
Evolução Biológica , Dente Molar/anatomia & histologia , Primatas/anatomia & histologia , Animais , Fósseis , Paleontologia , Wyoming
20.
Neuroimage ; 226: 117519, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33227425

RESUMO

Neuroimaging non-human primates (NHPs) is a growing, yet highly specialized field of neuroscience. Resources that were primarily developed for human neuroimaging often need to be significantly adapted for use with NHPs or other animals, which has led to an abundance of custom, in-house solutions. In recent years, the global NHP neuroimaging community has made significant efforts to transform the field towards more open and collaborative practices. Here we present the PRIMatE Resource Exchange (PRIME-RE), a new collaborative online platform for NHP neuroimaging. PRIME-RE is a dynamic community-driven hub for the exchange of practical knowledge, specialized analytical tools, and open data repositories, specifically related to NHP neuroimaging. PRIME-RE caters to both researchers and developers who are either new to the field, looking to stay abreast of the latest developments, or seeking to collaboratively advance the field .


Assuntos
Acesso à Informação , Neuroimagem/métodos , Sistemas On-Line , Primatas/anatomia & histologia , Primatas/fisiologia , Animais
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