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dc.identifier.urihttp://hdl.handle.net/11401/76955
dc.description.sponsorshipThis work is sponsored by the Stony Brook University Graduate School in compliance with the requirements for completion of degree.en_US
dc.formatMonograph
dc.format.mediumElectronic Resourceen_US
dc.language.isoen_US
dc.publisherThe Graduate School, Stony Brook University: Stony Brook, NY.
dc.typeDissertation
dcterms.abstractHuman manual dexterity is strongly enhanced by the presence of flattened nails associated with well-developed apical pads. However, the presence of nails is not unique to humans; it is one of the few traits that unite all living primates. Further, the form of the keratinous structure (nail, claw, etc.) on the ends of primate digits is often considered to be a diagnostic trait of major primate clades; strepsirrhines (lemurs, lorises, and galagos) possess a grooming claw (a specialized nail or claw used to scratch and clean the fur around the head and neck) on each second pedal digit; tarsiers possess one on each second and third pedal digit; and most anthropoids (monkeys, apes, and humans) lack one. However, relatively little is known about the, origin, diversity, and homologies of primate nails and grooming claws. This dissertation has two major objectives. The first is to determine the distribution, polarities, and homologies of grooming claws in extant and fossil primates and assess their significance for phylogenetic interpretations. The second is to elucidate patterns in distal phalanx morphology among arboreal mammals in order to better understand the circumstances surrounding the origin of primate nails. Data were collected from a sample of preserved digit tips (n=55) and distal phalanges from extant (n=1106) and fossil species (n=53). These were studied using a variety of methods including traditional and virtual dissection, high resolution imaging techniques, principal components analysis, discriminant function analysis, and ancestral state reconstructions. Major findings can be summarized as follows. Grooming claws are demonstrated to be present in omomyiform primates, and three lineages of platyrrhine monkeys (Aotus, Callicebus, and Pithecia). The likely ancestral condition of the second pedal digit of primates is to bear a grooming claw, and those of strepsirrhines and tarsiers are likely homologous. The presence of primate-like nails in a non-primate mammal that is small bodied (~9g) and inhabits a terminal branch niche (honey possums) is confirmed, and a relationship between primate-like morphology of the distal phalanx and small body size is shown. It is likely that small body size in early primates facilitated the origin of nails.
dcterms.available2017-09-20T16:51:31Z
dcterms.contributorJungers, William L.en_US
dcterms.contributorDemes, Brigitteen_US
dcterms.contributorBoyer, Dougen_US
dcterms.contributorLemelin, Pierre.en_US
dcterms.creatorMaiolino, Stephanie A.
dcterms.dateAccepted2017-09-20T16:51:31Z
dcterms.dateSubmitted2017-09-20T16:51:31Z
dcterms.descriptionDepartment of Anthropology.en_US
dcterms.extent209 pg.en_US
dcterms.formatApplication/PDFen_US
dcterms.formatMonograph
dcterms.identifierhttp://hdl.handle.net/11401/76955
dcterms.issued2015-12-01
dcterms.languageen_US
dcterms.provenanceMade available in DSpace on 2017-09-20T16:51:31Z (GMT). No. of bitstreams: 1 Maiolino_grad.sunysb_0771E_12377.pdf: 25389121 bytes, checksum: 95ab5b098cb6539de506db635d6d8149 (MD5) Previous issue date: 1en
dcterms.publisherThe Graduate School, Stony Brook University: Stony Brook, NY.
dcterms.subjectClaws, Distal Phalanx, Grooming Claws, Nails, Primate Evolution, Primate Origins
dcterms.subjectPhysical anthropology
dcterms.titleComparative Morphology of Primate Distal Phalanges: Implications for Early Primate Evolution and the Origins of the Primate Nail
dcterms.typeDissertation


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