Doug M Boyer
Biographic Data
| ID | 76849 |
|---|---|
| NAME | Doug M Boyer |
| GIVEN NAMES | Doug M |
| FAMILY NAME | Boyer |
| SIGNATURE | BOYER D M |
| AFFILIATIONS | Department of Evolutionary Anthropology Duke University Durham NC 27708 |
| VERIFIED | No |
| TOTAL WORKS | 54 |
| TOTAL CITATIONS | 623 |
| AUTHOR COUNT | 54 |
| EDITOR COUNT | 0 |
| FIRST PUBLICATION YEAR | 2002 |
| LATEST PUBLICATION YEAR | 2023 |
| H-INDEX | 16 |
Jumping performance in tree squirrels: Insights into primate evolution
Response to letters to the editor concerning Ajpa commentary on “data sharing in biological anthropology: Guiding principles and best practices”
First navicular remains of a European adapiform (Anchomomys frontanyensis) from the Middle Eocene of the Eastern Pyrenees (Catalonia, Spain): Implications for Early Primate Locomotor Behavior and Navi…
Carotid foramen size in the human skull tracks developmental changes in cerebral blood flow and brain metabolism
OBJECTIVES: In humans, neuronal processes related to brain development elevate the metabolic rate of brain tissue relative to the body during early childhood. This phenomenon has been hypothesized to contribute to slow somatic growth in preadolescent Homo sapiens. The uncoupling of the brain's metabolic rate from brain size during development complicates the study of the evolutionary emergence of these traits in the fossil record. Here, we extend…
New fossils, systematics, and biogeography of the oldest known crown primate Teilhardina from the earliest Eocene of Asia, Europe, and North America
My branch is your branch: Talar morphology correlates with relative substrate size in platyrrhines at Tiputini Biodiversity Station, Ecuador
New estimates of blood flow rates in the vertebral artery of euarchontans and their implications for encephalic blood flow scaling: A response to Seymour and Snelling (2018)
Oldest evidence for grooming claws in euprimates
Scaling of bony canals for encephalic vessels in euarchontans: Implications for the role of the vertebral artery and brain metabolism
The evolutionary radiation of plesiadapiforms
Very shortly after the disappearance of the non‐avian dinosaurs, the first mammals that had features similar to those of primates started appearing. These first primitive forms went on to spawn a rich diversity of plesiadapiforms, often referred to as archaic primates. Like many living primates, plesiadapiforms were small arboreal animals that generally ate fruit, insects, and, occasionally, leaves. However, this group lacked several diagnostic f…
Quantification of the position and depth of the flexor hallucis longus groove in euarchontans, with implications for the evolution of primate positional behavior
OBJECTIVE: On the talus, the position and depth of the groove for the flexor hallucis longus tendon have been used to infer phylogenetic affinities and positional behaviors of fossil primates. This study quantifies aspects of the flexor hallucis longus groove (FHLG) to test if: (1) a lateral FHLG is a derived strepsirrhine feature, (2) a lateral FHLG reflects inverted and abducted foot postures, and (3) a deeper FHLG indicates a larger muscle. ME…
Postcrania of the most primitive euprimate and implications for primate origins
Physical activity alters limb bone structure but not entheseal morphology
Lower molar shape and size in prosimian and platyrrhine primates
The goal of this research is to evaluate the relative strength of the influences of diet, size, and phylogenetic signal on dental geometric shape. Accurate comprehension of these factors and their interaction is important for reconstructing diet and deriving characters for a cladistic analysis in fossil primates. Geometric morphometric analysis is used to identify axes of shape variation in the lower second molars of (a) prosimian primates and (b…
The first major primate extinction: An evaluation of paleoecological dynamics of North American stem primates using a homology free measure of tooth shape
OBJECTIVES: The disappearance of the North American plesiadapoids (stem primates, or plesiadapiforms) in the latest Paleocene has been attributed to competition with rodents over dietary resources. This study compares molar morphology of plesiadapoids and early rodents to assess whether all taxa were adapted to consuming foods of the same structural properties with similar mechanical efficacy. MATERIALS AND METHODS: Micro-CT scans of second mandi…
Wear and its effects on dental topography measures in howling monkeys ( Alouatta palliata )
OBJECTIVES: Three dental topography measurements: Dirichlet Normal Energy (DNE), Relief Index (RFI), and Orientation Patch Count Rotated (OPCR) are examined for their interaction with measures of wear, within and between upper and lower molars in Alouatta palliata. Potential inferences of the "dental sculpting" phenomenon are explored. MATERIALS AND METHODS: Fifteen occluding pairs of howling monkey first molars (15 upper, 15 lower) opportunistic…
Astragalar and calcaneal morphology of the middle Eocene primate Anchomomys frontanyensis (Anchomomyini): Implications for early primate evolution
Stem members of Platyrrhini are distinct from catarrhines in at least one derived cranial feature
First virtual endocasts of adapiform primates
Internal carotid arterial canal size and scaling in Euarchonta: Re-assessing implications for arterial patency and phylogenetic relationships in early fossil primates
Primate Origins and Supraordinal Relationships: Morphological Evidence
The effect of differences in methodology among some recent applications of shearing quotients
A shearing quotient (SQ) is a way of quantitatively representing the Phase I shearing edges on a molar tooth. Ordinary or phylogenetic least squares regression is fit to data on log molar length (independent variable) and log sum of measured shearing crests (dependent variable). The derived linear equation is used to generate an ‘expected’ shearing crest length from molar length of included individuals or taxa. Following conversion of all variabl…
Evolution of postural diversity in primates as reflected by the size and shape of the medial tibial facet of the talus
OBJECTIVES: Comprehensive quantification of the shape and proportions of the medial tibial facet (MTF) of the talus (=astragalus) has been lacking for Primates and their closest relatives. In this study, aspects of MTF form were quantified and employed to test hypotheses about their functional and phylogenetic significance. The following hypotheses influence perceptions of primate evolutionary history but are due for more rigorous assessment: 1) …
Predicting euarchontan body mass: A comparison of tarsal and dental variables
Objective: Multiple meaningful ecological characterizations of a species revolve around body mass. Because body mass cannot be directly measured in extinct taxa, reliable body mass predictors are needed. Many published body mass prediction equations rely on dental dimensions, but certain skeletal dimensions may have a more direct and consistent relationship with body mass. We seek to evaluate the reliability of prediction equations for inferring …
Functional morphology of the hallucal metatarsal with implications for inferring grasping ability in extinct primates
Primate evolutionary morphologists have argued that selection for life in a fine branch niche resulted in grasping specializations that are reflected in the hallucal metatarsal (Mt1) morphology of extant “prosimians”, while a transition to use of relatively larger, horizontal substrates explains the apparent loss of such characters in anthropoids. Accordingly, these morphological characters—Mt1 torsion, peroneal process length and thickness, and …
Relief index of second mandibular molars is a correlate of diet among prosimian primates and other euarchontan mammals
Dental topography of platyrrhines and prosimians: Convergence and contrasts
Dental topographic analysis is the quantitative assessment of shape of three‐dimensional models of tooth crowns and component features. Molar topographic curvature, relief, and complexity correlate with aspects of feeding behavior in certain living primates, and have been employed to investigate dietary ecology in extant and extinct primate species. This study investigates whether dental topography correlates with diet among a diverse sample of l…
Comparing Dirichlet normal surface energy of tooth crowns, a new technique of molar shape quantification for dietary inference, with previous methods in isolation and in combination
Inferred dietary preference is a major component of paleoecologies of extinct primates. Molar occlusal shape correlates with diet in living mammals, so teeth are a potentially useful structure from which to reconstruct diet in extinct taxa. We assess the efficacy of Dirichlet normal energy (DNE) calculated for molar tooth surfaces for reflecting diet. We evaluate DNE, which uses changes in normal vectors to characterize curvature, by directly com…
Evolution of pedal grasping in Primates
Evidence of dietary differentiation among late Paleocene–early Eocene plesiadapids (Mammalia, primates)
Plesiadapis cookei is an extinct relative of extant euarchontans (primates, dermopterans; scandentians), which lived in North America during the late Paleocene. P. cookei body mass has been estimated to be ∼2.2 kg, making it large compared with other species of its genus from North America, but similar to some from Europe. In particular, size as well as dental form similarities to P. russelli have been noted. However, it is thought that P. russel…
Diet and dental topography in pitheciine seed predators
Pitheciines ( Pithecia , Chiropotes , and Cacajao ) are a specialized clade of Neotropical seed predators that exhibit postcanine teeth with low and rounded cusps and highly crenulated occlusal surface enamel. Data on feeding ecology show that Pithecia consumes proportionally more leaves than other pitheciine species, and comparative studies demonstrate its greater molar relief and relative shearing potential. However, data on pitheciine food mec…
Semicircular canal system in early primates
Intrinsic hand proportions of euarchontans and other mammals: Implications for the locomotor behavior of plesiadapiforms
New fossils of the oldest North American euprimate Teilhardina brandti (Omomyidae) from the paleocene–eocene thermal maximum
More than 25 new specimens of Teilhardina brandti , one of the oldest known euprimates, are reported from earliest Eocene strata of the southern Bighorn Basin, Wyoming. The new fossils include the first upper dentitions, a dentary showing the lower dental formula for the first time, and the first postcrania ascribed to T. brandti (tarsals and terminal phalanges). The elongated navicular and long talar neck suggest that T. brandti was an active ar…
Physical activity alters limb bone structure but not entheseal morphology
Patterns of astragalar fibular facet orientation in extant and fossil primates and their evolutionary implications
A laterally sloping fibular facet of the astragalus (=talus) has been proposed as one of few osteological synapomorphies of strepsirrhine primates, but the feature has never been comprehensively quantified. We describe a method for calculating fibular facet orientation on digital models of astragali as the angle between the planes of the fibular facet and the lateral tibial facet. We calculated this value in a sample that includes all major extan…
Hands of early primates
Questions surrounding the origin and early evolution of primates continue to be the subject of debate. Though anatomy of the skull and inferred dietary shifts are often the focus, detailed studies of postcrania and inferred locomotor capabilities can also provide crucial data that advance understanding of transitions in early primate evolution. In particular, the hand skeleton includes characteristics thought to reflect foraging, locomotion, and …
Astragalar and calcaneal morphology of the middle Eocene primate Anchomomys frontanyensis (Anchomomyini): Implications for early primate evolution
Astragalar morphology of Afradapis , a large adapiform primate from the earliest late Eocene of Egypt
The ∼37 million‐year‐old Birket Qarun Locality 2 (BQ‐2), in the Birket Qarun Formation of Egypt's Fayum Depression, yields evidence for a diverse primate fauna, including the earliest known lorisiforms, parapithecoid anthropoids, and Afradapis longicristatus , a large folivorous adapiform. Phylogenetic analysis has placed Afradapis as a stem strepsirrhine within a clade of caenopithecine adapiforms, contradicting the recently popularized alternat…
Predicting euarchontan body mass: A comparison of tarsal and dental variables
Objective: Multiple meaningful ecological characterizations of a species revolve around body mass. Because body mass cannot be directly measured in extinct taxa, reliable body mass predictors are needed. Many published body mass prediction equations rely on dental dimensions, but certain skeletal dimensions may have a more direct and consistent relationship with body mass. We seek to evaluate the reliability of prediction equations for inferring …
Dental topography indicates ecological contraction of lemur communities
Understanding the paleoecology of extinct subfossil lemurs requires reconstruction of dietary preferences. Tooth morphology is strongly correlated with diet in living primates and is appropriate for inferring dietary ecology. Recently, dental topographic analysis has shown great promise in reconstructing diet from molar tooth form. Compared with traditionally used shearing metrics, dental topography is better suited for the extraordinary diversit…
Evolution of postural diversity in primates as reflected by the size and shape of the medial tibial facet of the talus
OBJECTIVES: Comprehensive quantification of the shape and proportions of the medial tibial facet (MTF) of the talus (=astragalus) has been lacking for Primates and their closest relatives. In this study, aspects of MTF form were quantified and employed to test hypotheses about their functional and phylogenetic significance. The following hypotheses influence perceptions of primate evolutionary history but are due for more rigorous assessment: 1) …
Wear and its effects on dental topography measures in howling monkeys ( Alouatta palliata )
OBJECTIVES: Three dental topography measurements: Dirichlet Normal Energy (DNE), Relief Index (RFI), and Orientation Patch Count Rotated (OPCR) are examined for their interaction with measures of wear, within and between upper and lower molars in Alouatta palliata. Potential inferences of the "dental sculpting" phenomenon are explored. MATERIALS AND METHODS: Fifteen occluding pairs of howling monkey first molars (15 upper, 15 lower) opportunistic…
Postcrania of the most primitive euprimate and implications for primate origins
The first major primate extinction: An evaluation of paleoecological dynamics of North American stem primates using a homology free measure of tooth shape
OBJECTIVES: The disappearance of the North American plesiadapoids (stem primates, or plesiadapiforms) in the latest Paleocene has been attributed to competition with rodents over dietary resources. This study compares molar morphology of plesiadapoids and early rodents to assess whether all taxa were adapted to consuming foods of the same structural properties with similar mechanical efficacy. MATERIALS AND METHODS: Micro-CT scans of second mandi…
New craniodental material of Pronothodectes gaoi Fox (Mammalia, “Plesiadapiformes”) and relationships among members of Plesiadapidae
Plesiadapidae are a family of Paleogene mammals thought to have phylogenetic affinities with modern Primates. We describe previously unpublished dentitions and the first skull and isolated petrosals of the plesiadapid Pronothodectes gaoi , collected from middle Tiffanian localities of the Paskapoo Formation in Alberta. Other species of Pronothodectes , traditionally considered the most basal members of the Plesiadapidae, occur at earlier, Torrejo…
New primate first metatarsals from the Paleogene of Egypt and the origin of the anthropoid big toe
A calcaneus attributable to the primitive late eocene anthropoid Proteopithecus sylviae: Phenetic affinities and phylogenetic implications
A well‐preserved calcaneus referrable to Proteopithecus sylviae from the late Eocene Quarry L‐41 in the Fayum Depression, Egypt, provides new evidence relevant to this taxon's uncertain phylogenetic position. We assess morphological affinities of the new specimen using three‐dimensional geometric morphometric analyses with a comparative sample of primate calcanei representing major extinct and extant radiations ( n = 58 genera, 106 specimens). Ou…
New fossils, systematics, and biogeography of the oldest known crown primate Teilhardina from the earliest Eocene of Asia, Europe, and North America
The effect of differences in methodology among some recent applications of shearing quotients
A shearing quotient (SQ) is a way of quantitatively representing the Phase I shearing edges on a molar tooth. Ordinary or phylogenetic least squares regression is fit to data on log molar length (independent variable) and log sum of measured shearing crests (dependent variable). The derived linear equation is used to generate an ‘expected’ shearing crest length from molar length of included individuals or taxa. Following conversion of all variabl…
Grasping Primate Origins
The evolutionary history that led to Eocene-and-later primates of modern aspect (Euprimates) has been uncertain. We describe a skeleton of Paleocene plesiadapiform Carpolestes simpsoni that includes most of the skull and many postcranial bones. Phylogenetic analyses indicate that Carpolestidae are closely related to Euprimates. C. simpsoni had long fingers and an opposable hallux with a nail. It lacked orbital convergence and an ankle specialized…
Primate Origins and Supraordinal Relationships: Morphological Evidence
New Paleocene skeletons and the relationship of plesiadapiforms to crown-clade primates
Plesiadapiforms are central to studies of the origin and evolution of primates and other euarchontan mammals (tree shrews and flying lemurs). We report results from a comprehensive cladistic analysis using cranial, postcranial, and dental evidence including data from recently discovered Paleocene plesiadapiform skeletons ( Ignacius clarkforkensis sp. nov.; Dryomomys szalayi , gen. et sp. nov.), and the most plesiomorphic extant tree shrew, Ptiloc…
Revisiting the adaptive origins of primates (again)
Evolution of pedal grasping in Primates
Relief index of second mandibular molars is a correlate of diet among prosimian primates and other euarchontan mammals
Intrinsic hand proportions of euarchontans and other mammals: Implications for the locomotor behavior of plesiadapiforms
Comparative functional morphology of the primate peroneal process
Semicircular canal system in early primates
Evidence of dietary differentiation among late Paleocene–early Eocene plesiadapids (Mammalia, primates)
Plesiadapis cookei is an extinct relative of extant euarchontans (primates, dermopterans; scandentians), which lived in North America during the late Paleocene. P. cookei body mass has been estimated to be ∼2.2 kg, making it large compared with other species of its genus from North America, but similar to some from Europe. In particular, size as well as dental form similarities to P. russelli have been noted. However, it is thought that P. russel…
Astragalar morphology of Afradapis , a large adapiform primate from the earliest late Eocene of Egypt
The ∼37 million‐year‐old Birket Qarun Locality 2 (BQ‐2), in the Birket Qarun Formation of Egypt's Fayum Depression, yields evidence for a diverse primate fauna, including the earliest known lorisiforms, parapithecoid anthropoids, and Afradapis longicristatus , a large folivorous adapiform. Phylogenetic analysis has placed Afradapis as a stem strepsirrhine within a clade of caenopithecine adapiforms, contradicting the recently popularized alternat…
Hallucal grasping in Nycticebus coucang: Further Implications for the Functional Significance of a Large Peroneal Process
New fossils of the oldest North American euprimate Teilhardina brandti (Omomyidae) from the paleocene–eocene thermal maximum
More than 25 new specimens of Teilhardina brandti , one of the oldest known euprimates, are reported from earliest Eocene strata of the southern Bighorn Basin, Wyoming. The new fossils include the first upper dentitions, a dentary showing the lower dental formula for the first time, and the first postcrania ascribed to T. brandti (tarsals and terminal phalanges). The elongated navicular and long talar neck suggest that T. brandti was an active ar…
Changes in orientation of attritional wear facets with implications for jaw motion in a mixed longitudinal sample of Propithecus edwardsi from Ranomafana National Park, Madagascar
In many mammalian species, the progressive wearing down of the teeth that occurs over an individual's lifetime has the potential to change dental function, jaw movements, or even feeding habits. The orientation of phase‐I wear facets on molars reveals the direction of jaw movement during the power stroke of mastication. We investigated if and how molar wear facets change with increasing wear and/or age by examining a mixed longitudinal dataset of…
Comparing Dirichlet normal surface energy of tooth crowns, a new technique of molar shape quantification for dietary inference, with previous methods in isolation and in combination
Inferred dietary preference is a major component of paleoecologies of extinct primates. Molar occlusal shape correlates with diet in living mammals, so teeth are a potentially useful structure from which to reconstruct diet in extinct taxa. We assess the efficacy of Dirichlet normal energy (DNE) calculated for molar tooth surfaces for reflecting diet. We evaluate DNE, which uses changes in normal vectors to characterize curvature, by directly com…
Relationships between the expression of the stapedial artery and the size of the obturator foramen in euarchontans: Functional and phylogenetic implications
Earliest record of Platychoerops (Primates, Plesiadapidae), a new species from Mouras Quarry, Mont de Berru, France
Plesiadapids are extinct relatives of extant euarchontans (primates, dermopterans, and scandentians), which lived in North America and Europe during the Paleocene and Early Eocene. The only genus of plesiadapid whose species are absent from Paleocene strata is Platychoerops . Further, Platychoerops is the only group found in sediments post‐dating the Paleocene‐Eocene boundary (PEB) by a substantial period of time based on large samples. It is als…
Lemur habitat and dental senescence in Ranomafana National Park, Madagascar
Not only can teeth provide clues about diet, but they also can be indicators of habitat quality. Conspecific groups living in different habitats with different kinds of foods may exhibit different rates of dental attrition because their teeth are less well adapted to some foods than to others. Ecological disequilibrium describes the situation in which animals live in habitats to which they are relatively poorly adapted. We test whether dental sen…
Dental topography indicates ecological contraction of lemur communities
Understanding the paleoecology of extinct subfossil lemurs requires reconstruction of dietary preferences. Tooth morphology is strongly correlated with diet in living primates and is appropriate for inferring dietary ecology. Recently, dental topographic analysis has shown great promise in reconstructing diet from molar tooth form. Compared with traditionally used shearing metrics, dental topography is better suited for the extraordinary diversit…
New craniodental material of Pronothodectes gaoi Fox (Mammalia, “Plesiadapiformes”) and relationships among members of Plesiadapidae
Plesiadapidae are a family of Paleogene mammals thought to have phylogenetic affinities with modern Primates. We describe previously unpublished dentitions and the first skull and isolated petrosals of the plesiadapid Pronothodectes gaoi , collected from middle Tiffanian localities of the Paskapoo Formation in Alberta. Other species of Pronothodectes , traditionally considered the most basal members of the Plesiadapidae, occur at earlier, Torrejo…
New primate first metatarsals from the Paleogene of Egypt and the origin of the anthropoid big toe
Morphological Evidence for Primate Origins and Supraordinal Relationships
Patterns of astragalar fibular facet orientation in extant and fossil primates and their evolutionary implications
A laterally sloping fibular facet of the astragalus (=talus) has been proposed as one of few osteological synapomorphies of strepsirrhine primates, but the feature has never been comprehensively quantified. We describe a method for calculating fibular facet orientation on digital models of astragali as the angle between the planes of the fibular facet and the lateral tibial facet. We calculated this value in a sample that includes all major extan…
A calcaneus attributable to the primitive late eocene anthropoid Proteopithecus sylviae: Phenetic affinities and phylogenetic implications
A well‐preserved calcaneus referrable to Proteopithecus sylviae from the late Eocene Quarry L‐41 in the Fayum Depression, Egypt, provides new evidence relevant to this taxon's uncertain phylogenetic position. We assess morphological affinities of the new specimen using three‐dimensional geometric morphometric analyses with a comparative sample of primate calcanei representing major extinct and extant radiations ( n = 58 genera, 106 specimens). Ou…
Hands of early primates
Questions surrounding the origin and early evolution of primates continue to be the subject of debate. Though anatomy of the skull and inferred dietary shifts are often the focus, detailed studies of postcrania and inferred locomotor capabilities can also provide crucial data that advance understanding of transitions in early primate evolution. In particular, the hand skeleton includes characteristics thought to reflect foraging, locomotion, and …
Biology (51 works) · Primate Behavior and Ecology (48 works) · Evolutionary biology (34 works) · Evolution and Paleontology Studies (32 works) · Paleontology (31 works) · Anatomy (30 works) · Anatomy (29 works) · Paleontology (29 works) · Primate (29 works) · Ecology (25 works)