Alejandro Pérez-Pérez | Universitat de Barcelona (original) (raw)
Papers by Alejandro Pérez-Pérez
The phylogenetic position of many fossil platyrrhines with respect to extant ones is not yet clea... more The phylogenetic position of many fossil platyrrhines with respect to extant ones is not yet clear. Two main hypotheses have been proposed: the layered or successive radiations hypothesis suggests that Patagonian fossils are Middle Miocene stem platyrrhines lacking modern descendants, whereas the long lineage hypothesis argues for an evolutionary continuity of all fossil platyrrhines with the extant ones. Our geometric morphometric analysis of a 15 landmark-based configuration of platyrrhines’ first and second lower molars suggest that morphological stasis may explain the reduced molar shape variation observed. Platyrrhine lower molar shape might be a primitive retention of the ancestral state affected by strong ecological constraints throughout the radiation of the main platyrrhine families. The Patagonian fossil specimens showed two distinct morphological patterns of lower molars, Callicebus—like and Saguinus—like, which might be the precursors of the extant forms, whereas the Middle Miocene specimens, though showing morphological resemblances with the Patagonian fossils, also displayed new, derived molar patterns, Alouatta—like and Pitheciinae—like, thereby suggesting that despite the overall morphological stasis of molars, phenotypic diversification of molar shape was already settled during the Middle Miocene
ABSTRACT http://www.oxbowbooks.com/oxbow/wild-harvest.html
The reconstruction the diet and dietary related habits of our ancestors is very informative about... more The reconstruction the diet and dietary related habits of our ancestors is very informative about their evolutionary behaviour and adaptability. One method to infer diet from skeletal remains is to study the dental microwear pattern of teeth, since these constitute the most abundant remains in the fossil record. By using dental enamel microwear as a direct evidence for food consumption, we can obtain direct evidence of hominid ecology and adaptation to fluctuating environments. During mastication, food repeatedly contacts with dental enamel and abrasive particles, such as phytoliths present in plant tissues, are bound to scratch and rub the enamel surface of teeth. Many fossil teeth generally show poor enamel preservation caused by post-mortem damage, not informative of diet. Therefore, knowledge of ante-mortem buccal microwear variability as well as post-mortem enamel damage is required to make dietary inferences on fossil human populations. The absence of striation-like features o...
Journal of Morphology, 2018
Molars are highly integrated biological structures that have been used for inferring evolutionary... more Molars are highly integrated biological structures that have been used for inferring evolutionary relationships among taxa. However, parallel and convergent morphological traits can be affected by developmental and functional constraints. Here, we analyze molar shapes of platyrrhines in order to explore if platyrrhine molar diversity reflects homogeneous patterns of molar variation and covariation. We digitized 30 landmarks on mandibular first and second molars of 418 extant and 11 fossil platyrrhine specimens to determine the degree of integration of both molars when treated as a single module. We combined morphological and phylogenetic data to investigate the phylogenetic signal and to visualize the history of molar shape changes. All platyrrhine taxa show a common shape pattern suggesting that a relatively low degree of phenotypic variation is caused by convergent evolution, although molar shape carries significant phylogenetic signal. Atelidae and Pitheciidae show high levels of integration with low variation between the two molars, whereas the Cebinae/Saimiriinae, and especially Callitrichinae, show greater variation between molars and trend toward a modular organization. We hypothesize that biomechanical constraints of the masticatory apparatus, and the dietary profile of each taxon are the main factors that determine high covariation in molars. In contrast, low molar shape covariation may result from the fact that each molar exhibits a distinct ecological signal, as molars can be exposed to distinct occlusal loadings during food processing, suggesting that different selective pressures on molars can reduce overall molar integration.
American journal of physical anthropology, Jul 22, 2018
Odontometric studies of African populations show high within-group variation in tooth size. Overa... more Odontometric studies of African populations show high within-group variation in tooth size. Overall, North Africans exhibit smaller dimensions than groups from eastern and southern sub-Saharan regions, but no previous studies have analyzed the full dental metrics among extant African Pygmy hunter-gatherers and Bantu-speaking farmers. Furthermore, the population variability in tooth crown sizes from equatorial rainforest regions remains to be elucidated. The mesiodistal and buccolingual diameters of the permanent teeth (I1-M2) were measured in vivo using high-resolution replicas from Baka Pygmies and Mvae and Yassa Bantu-speakers from Cameroon (western Africa). Analyses of variance were used to record sex-related and population-level differences in tooth sizes, and a principal component analysis of geometrically scaled measures was used to plot the odontometric variability among groups. Cameroonian Baka Pygmies differ in dental size from their Bantu-speaking neighbors. Molar teeth ar...
Anthropologischer Anzeiger; Bericht uber die biologisch-anthropologische Literatur, Jan 5, 2016
Ethnographic studies indicate that Eskimo foragers are characterized by well-defined sexual divis... more Ethnographic studies indicate that Eskimo foragers are characterized by well-defined sexual division of labor and extensive use of anterior teeth as a tool, resulting in higher degrees of wear. However, little is known about the intra-population variation in molar-macrowear rates and dietary implications. Here, percentages of dentin exposure (PDE) were recorded on first mandibular molars among Tigara foragers from Point Hope (Alaska) and attempt to correlate age and sex variation in wear patterns. We found that no overall sex-related differences in PDE exist and suggest that molars did not take a part in para-masticatory or cultural practices. Strong correlation with increasing age was found as expected but males wore their teeth at higher rates than females related to masticatory demands during growth. Our findings suggest that individual variation in molar-macrowear must be attributed to biomechanics of chewing and cultural behavior rather than sexual variation in food acquisition.
Vertebrate Paleobiology and Paleoanthropology, 2007
Dental microwear analysis is based on the assumption that a correlation exists between ingested d... more Dental microwear analysis is based on the assumption that a correlation exists between ingested diet and microwear patterns on the enamel surface of teeth, such that diet can be reconstructed by quantifying enamel microwear. Abrasive particles, such as plant phytoliths or silica-based sands incorporated into food items, along with food processing techniques and tooth morphology, are responsible for the microwear
La microestriación o microdesgaste dental (dental microwear) se define como el conjunto de altera... more La microestriación o microdesgaste dental (dental microwear) se define como el conjunto de altera-ciones físicas microscópicas producidas en la superficie del esmalte dental y que resultan de la interac-ción entre las partículas abrasivas presentes en los alimentos durante su masticación. Por tanto, el análi-sis de las abrasiones que las características físicas y mecánicas de los alimentos producen sobre el esmal-te, nos puede ayudar a entender la adaptación de una especie o población a un tipo de dieta, así como a sus características naturales o artificiales, en función de los medios de preparación o conservación. Hoy sabemos que las microestrías se producen por partículas abrasivas de dureza igual o superior a la del propio esmalte. En 1824, el geólogo austríaco Friedrich Mohs publicó una escala de dureza relativa de los minerales. Esta escala, conocida como escala de Mohs clasifica entre los valores 1 y 10 la dureza de los minerales desde el talco (con el valor 1) hasta el diaman...
Primates, 2009
Buccal microwear patterns on teeth are good indicators of the abrasiveness of foodstuffs and have... more Buccal microwear patterns on teeth are good indicators of the abrasiveness of foodstuffs and have been used to trace the dietary habits of fossil species, including primates and hominids. However, few studies have addressed the variability of this microwear. The abrasiveness of dietary components depends not only on the hardness of the particles ingested, but also on the presence of dust and other exogenous elements introduced during food processing. These elements are responsible for the microwear typology observed on the enamel surfaces of primate teeth. Here we analyzed the variability of buccal microwear patterns in African Great Apes (Gorilla gorilla and Pan troglodytes), using tooth molds obtained from the original specimens held in several osteological collections. Our results suggest that ecological adaptations at subspecies or population level account for differences in microwear patterns, which are attributed to habitat and ecological conditions within populations rather than differences between species. The findings from studies on the variability of buccal dental microwear in extant species will contribute to a better understanding of extinct hominids' diet and ecology.
Quarhis, 2008
Acceso de usuarios registrados. Acceso de usuarios registrados Usuario Contraseña. ...
American Journal of Physical Anthropology, 2003
Ancient mtDNA was succesfully recovered from 24 skeletal samples of a total of 60 ancient individ... more Ancient mtDNA was succesfully recovered from 24 skeletal samples of a total of 60 ancient individuals from Patagonia-Tierra del Fuego, dated to 100-400 years BP, for which consistent amplifications and two-strand sequences were obtained. Y-chromosome STRs (DYS434, DYS437, DYS439, DYS393, DYS391, DYS390, DYS19, DYS389I, DYS389II, and DYS388) and the biallelic system DYS199 were also amplified, Y-STR alleles could be characterized in nine cases, with an average of 4.1 loci per sample correctly typed. In two samples of the same ethnic group (Aonikenk), an identical and complete eight-loci haplotype was recovered. The DYS199 biallelic system was used as a control of contamination by modern DNA and, along with DYS19, as a marker of American origin. The analysis of both mtDNA and Y-STRs revealed DNA from Amerindian ancestry. The observed polymorphisms are consistent with the hypothesis that the ancient Fuegians are close to populations from southcentral Chile and Argentina, but their high nucleotide diversity and the frequency of single lineages strongly support early genetic differentiation of the Fuegians through combined processes of population bottleneck, isolation, and/or migration, followed by strong genetic drift. This suggests an early genetic diversification of the Fuegians right after their arrival at the southernmost extreme of South America. Am J Phys Anthropol 123: 361-370, 2004.
Journal of Anthropological Sciences, 2012
Molar occlusal microwear texture and anisotropy analyses of 3 Australopithecus anamensis fossil s... more Molar occlusal microwear texture and anisotropy analyses of 3 Australopithecus anamensis fossil specimens have shown complexity values similar to those of Au. afarensis, indicating that neither of these hominin species had a diet dominated by hard food. However, many researchers have suggested that these were some of the earliest hominins to have such diets. Here we examine buccal microwear patterns of 5 Au. anamensis, 26 Au. afarensis, 48 Hominoidea and 80 Cercopithecoidea primate specimens for independent evidence of dietary adaptations of Au. anamensis. The buccal microwear results obtained suggest that the diet of Au. anamensis relied heavily on hard, brittle food, at least seasonally. This is similar to the diet of the extant Cercopithecoidea primates, including Papio anubis and Chlorocebus aethiops, both of which live in wooded, seasonal savannah environments and have diets that include fruit and grasses, but also underground storage organs (USOs), such as corms or blades, as well as leaves and seeds, and also Mandrillus and Cercocebus, from forested environments with frugivorous-granivorous diets. Furthermore, the buccal microwear patterns of Au. anamensis and Au. afarensis clearly differed-in clear contrast to occlusal enamel texture observations-which support previous dietary interpretations based on both anatomical and palaeocological reconstructions.
American Journal of Physical Anthropology
Anthropologischer Anzeiger
Syria
-Le phénomène de diffusion du Néolithique depuis le Proche-Orient vers l'Europe et son influence ... more -Le phénomène de diffusion du Néolithique depuis le Proche-Orient vers l'Europe et son influence sur la néolithisation de l'Europe a été abordé par diverses disciplines. L'analyse génétique des populations humaines récentes a donné des résultats contradictoires. Tandis que la distribution et les fréquences allele des « marqueurs classiques » (groupes sanguins et protéines), et la variabilité moléculaire du chromosome Y confortent le modèle de diffusion démique, la variabilité de l'ADN mitochondrie nous propose une origine surtout paléolithique des populations européennes actuelles, avec une petite contribution néolithique depuis le Proche-Orient. L'analyse génétique des échantillons biologiques nous permet d'établir cette hypothèse. Dans ce travail, nous avons étudié la variabilité mitochondrial de sept individus du néolithique PPNB de Tell Ramad (Syrie). Les séquences d'ADN mitochondrial obtenues sont très similaires à celles trouvées aujourd'hui en Europe et au Proche-Orient, et elles suggèrent que, dans cette région, il y aurait une continuité génétique depuis le Néolithique.
Journal of Archaeological Science: Reports
Folia primatologica; international journal of primatology, Jan 12, 2018
Vertical clinging is a specialized form of locomotion characteristic of the primate family Callit... more Vertical clinging is a specialized form of locomotion characteristic of the primate family Callitrichidae. Vertical clinging requires these pronograde primates to maintain a vertical posture, so the protraction of their forelimbs must resist gravity. Since pronograde primates usually move as horizontal quadrupeds, we hypothesized that the supraspinatus muscle of vertical clingers would present specific characteristics related to the functional requirements imposed on the shoulder area by vertical clinging. To test this hypothesis, we quantified by real-time quantitative polymerase chain reaction the mRNA transcripts of myosin heavy chain (MHC) isoforms in the supraspinatus muscle of 15 species of pronograde primates, including vertical clingers. Our results indicate that the supraspinatus of vertical clingers has a specific expression pattern of the MHC isoforms, with a low expression of the transcripts of the slow MHC-I isoform and a high expression of the transcripts of the fast M...
PloS one, 2017
Analyses of dental micro- and macro-wear offer valuable information about dietary adaptations. Th... more Analyses of dental micro- and macro-wear offer valuable information about dietary adaptations. The buccal surface of the teeth does not undergo attrition, indicating that dental microwear may directly inform about food properties. Only a few studies have, however, investigated the environmental and individual factors involved in the formation of such microwear in wild animals. Here, we examine variation of buccal microwear patterns of mandibular molars in a large free-ranging population of mandrills (Mandrillus sphinx). We first explore the influence of seasonality and individual's sex, age and tooth macrowear-expressed as the percent of dentine exposure (PDE)-on six microwear variables. Second, we analyze the interplay between individual's diet and PDE. In a last analysis, we revisit our results on mandrills in the light of other primate's microwear studies. We show that the average buccal scratch length and the frequency of vertical buccal scratches are both higher dur...
Archives of oral biology, Jan 9, 2017
The aim of this study is to examine the expression pattern of the different myosin heavy chain (M... more The aim of this study is to examine the expression pattern of the different myosin heavy chain (MyHC) isoforms in the masseter and medial pterygoid muscles by real time quantitative polymerase chain reaction (RT-qPCR) to obtain information at molecular level which can be related to the functional characteristics of these two muscles. The masseter, deep and superficial portion, and medial pterygoid muscles of five adult Pan troglodytes were dissected in order to obtain samples of the anterior and posterior regions of each portion of the masseter and of the medial pterygoid. The expression of MyHC isoforms mRNA transcripts was analyzed by RT-qPCR. No significant differences in expression of MyHC isoforms between the masseter and the medial pterygoid were found. In contrast, when comparing the superficial and the deep portion of the masseter, we found that the MyHC-IIM isoform was expressed at a significantly higher level in the superficial portion. The superficial portion of the masse...
The phylogenetic position of many fossil platyrrhines with respect to extant ones is not yet clea... more The phylogenetic position of many fossil platyrrhines with respect to extant ones is not yet clear. Two main hypotheses have been proposed: the layered or successive radiations hypothesis suggests that Patagonian fossils are Middle Miocene stem platyrrhines lacking modern descendants, whereas the long lineage hypothesis argues for an evolutionary continuity of all fossil platyrrhines with the extant ones. Our geometric morphometric analysis of a 15 landmark-based configuration of platyrrhines’ first and second lower molars suggest that morphological stasis may explain the reduced molar shape variation observed. Platyrrhine lower molar shape might be a primitive retention of the ancestral state affected by strong ecological constraints throughout the radiation of the main platyrrhine families. The Patagonian fossil specimens showed two distinct morphological patterns of lower molars, Callicebus—like and Saguinus—like, which might be the precursors of the extant forms, whereas the Middle Miocene specimens, though showing morphological resemblances with the Patagonian fossils, also displayed new, derived molar patterns, Alouatta—like and Pitheciinae—like, thereby suggesting that despite the overall morphological stasis of molars, phenotypic diversification of molar shape was already settled during the Middle Miocene
ABSTRACT http://www.oxbowbooks.com/oxbow/wild-harvest.html
The reconstruction the diet and dietary related habits of our ancestors is very informative about... more The reconstruction the diet and dietary related habits of our ancestors is very informative about their evolutionary behaviour and adaptability. One method to infer diet from skeletal remains is to study the dental microwear pattern of teeth, since these constitute the most abundant remains in the fossil record. By using dental enamel microwear as a direct evidence for food consumption, we can obtain direct evidence of hominid ecology and adaptation to fluctuating environments. During mastication, food repeatedly contacts with dental enamel and abrasive particles, such as phytoliths present in plant tissues, are bound to scratch and rub the enamel surface of teeth. Many fossil teeth generally show poor enamel preservation caused by post-mortem damage, not informative of diet. Therefore, knowledge of ante-mortem buccal microwear variability as well as post-mortem enamel damage is required to make dietary inferences on fossil human populations. The absence of striation-like features o...
Journal of Morphology, 2018
Molars are highly integrated biological structures that have been used for inferring evolutionary... more Molars are highly integrated biological structures that have been used for inferring evolutionary relationships among taxa. However, parallel and convergent morphological traits can be affected by developmental and functional constraints. Here, we analyze molar shapes of platyrrhines in order to explore if platyrrhine molar diversity reflects homogeneous patterns of molar variation and covariation. We digitized 30 landmarks on mandibular first and second molars of 418 extant and 11 fossil platyrrhine specimens to determine the degree of integration of both molars when treated as a single module. We combined morphological and phylogenetic data to investigate the phylogenetic signal and to visualize the history of molar shape changes. All platyrrhine taxa show a common shape pattern suggesting that a relatively low degree of phenotypic variation is caused by convergent evolution, although molar shape carries significant phylogenetic signal. Atelidae and Pitheciidae show high levels of integration with low variation between the two molars, whereas the Cebinae/Saimiriinae, and especially Callitrichinae, show greater variation between molars and trend toward a modular organization. We hypothesize that biomechanical constraints of the masticatory apparatus, and the dietary profile of each taxon are the main factors that determine high covariation in molars. In contrast, low molar shape covariation may result from the fact that each molar exhibits a distinct ecological signal, as molars can be exposed to distinct occlusal loadings during food processing, suggesting that different selective pressures on molars can reduce overall molar integration.
American journal of physical anthropology, Jul 22, 2018
Odontometric studies of African populations show high within-group variation in tooth size. Overa... more Odontometric studies of African populations show high within-group variation in tooth size. Overall, North Africans exhibit smaller dimensions than groups from eastern and southern sub-Saharan regions, but no previous studies have analyzed the full dental metrics among extant African Pygmy hunter-gatherers and Bantu-speaking farmers. Furthermore, the population variability in tooth crown sizes from equatorial rainforest regions remains to be elucidated. The mesiodistal and buccolingual diameters of the permanent teeth (I1-M2) were measured in vivo using high-resolution replicas from Baka Pygmies and Mvae and Yassa Bantu-speakers from Cameroon (western Africa). Analyses of variance were used to record sex-related and population-level differences in tooth sizes, and a principal component analysis of geometrically scaled measures was used to plot the odontometric variability among groups. Cameroonian Baka Pygmies differ in dental size from their Bantu-speaking neighbors. Molar teeth ar...
Anthropologischer Anzeiger; Bericht uber die biologisch-anthropologische Literatur, Jan 5, 2016
Ethnographic studies indicate that Eskimo foragers are characterized by well-defined sexual divis... more Ethnographic studies indicate that Eskimo foragers are characterized by well-defined sexual division of labor and extensive use of anterior teeth as a tool, resulting in higher degrees of wear. However, little is known about the intra-population variation in molar-macrowear rates and dietary implications. Here, percentages of dentin exposure (PDE) were recorded on first mandibular molars among Tigara foragers from Point Hope (Alaska) and attempt to correlate age and sex variation in wear patterns. We found that no overall sex-related differences in PDE exist and suggest that molars did not take a part in para-masticatory or cultural practices. Strong correlation with increasing age was found as expected but males wore their teeth at higher rates than females related to masticatory demands during growth. Our findings suggest that individual variation in molar-macrowear must be attributed to biomechanics of chewing and cultural behavior rather than sexual variation in food acquisition.
Vertebrate Paleobiology and Paleoanthropology, 2007
Dental microwear analysis is based on the assumption that a correlation exists between ingested d... more Dental microwear analysis is based on the assumption that a correlation exists between ingested diet and microwear patterns on the enamel surface of teeth, such that diet can be reconstructed by quantifying enamel microwear. Abrasive particles, such as plant phytoliths or silica-based sands incorporated into food items, along with food processing techniques and tooth morphology, are responsible for the microwear
La microestriación o microdesgaste dental (dental microwear) se define como el conjunto de altera... more La microestriación o microdesgaste dental (dental microwear) se define como el conjunto de altera-ciones físicas microscópicas producidas en la superficie del esmalte dental y que resultan de la interac-ción entre las partículas abrasivas presentes en los alimentos durante su masticación. Por tanto, el análi-sis de las abrasiones que las características físicas y mecánicas de los alimentos producen sobre el esmal-te, nos puede ayudar a entender la adaptación de una especie o población a un tipo de dieta, así como a sus características naturales o artificiales, en función de los medios de preparación o conservación. Hoy sabemos que las microestrías se producen por partículas abrasivas de dureza igual o superior a la del propio esmalte. En 1824, el geólogo austríaco Friedrich Mohs publicó una escala de dureza relativa de los minerales. Esta escala, conocida como escala de Mohs clasifica entre los valores 1 y 10 la dureza de los minerales desde el talco (con el valor 1) hasta el diaman...
Primates, 2009
Buccal microwear patterns on teeth are good indicators of the abrasiveness of foodstuffs and have... more Buccal microwear patterns on teeth are good indicators of the abrasiveness of foodstuffs and have been used to trace the dietary habits of fossil species, including primates and hominids. However, few studies have addressed the variability of this microwear. The abrasiveness of dietary components depends not only on the hardness of the particles ingested, but also on the presence of dust and other exogenous elements introduced during food processing. These elements are responsible for the microwear typology observed on the enamel surfaces of primate teeth. Here we analyzed the variability of buccal microwear patterns in African Great Apes (Gorilla gorilla and Pan troglodytes), using tooth molds obtained from the original specimens held in several osteological collections. Our results suggest that ecological adaptations at subspecies or population level account for differences in microwear patterns, which are attributed to habitat and ecological conditions within populations rather than differences between species. The findings from studies on the variability of buccal dental microwear in extant species will contribute to a better understanding of extinct hominids' diet and ecology.
Quarhis, 2008
Acceso de usuarios registrados. Acceso de usuarios registrados Usuario Contraseña. ...
American Journal of Physical Anthropology, 2003
Ancient mtDNA was succesfully recovered from 24 skeletal samples of a total of 60 ancient individ... more Ancient mtDNA was succesfully recovered from 24 skeletal samples of a total of 60 ancient individuals from Patagonia-Tierra del Fuego, dated to 100-400 years BP, for which consistent amplifications and two-strand sequences were obtained. Y-chromosome STRs (DYS434, DYS437, DYS439, DYS393, DYS391, DYS390, DYS19, DYS389I, DYS389II, and DYS388) and the biallelic system DYS199 were also amplified, Y-STR alleles could be characterized in nine cases, with an average of 4.1 loci per sample correctly typed. In two samples of the same ethnic group (Aonikenk), an identical and complete eight-loci haplotype was recovered. The DYS199 biallelic system was used as a control of contamination by modern DNA and, along with DYS19, as a marker of American origin. The analysis of both mtDNA and Y-STRs revealed DNA from Amerindian ancestry. The observed polymorphisms are consistent with the hypothesis that the ancient Fuegians are close to populations from southcentral Chile and Argentina, but their high nucleotide diversity and the frequency of single lineages strongly support early genetic differentiation of the Fuegians through combined processes of population bottleneck, isolation, and/or migration, followed by strong genetic drift. This suggests an early genetic diversification of the Fuegians right after their arrival at the southernmost extreme of South America. Am J Phys Anthropol 123: 361-370, 2004.
Journal of Anthropological Sciences, 2012
Molar occlusal microwear texture and anisotropy analyses of 3 Australopithecus anamensis fossil s... more Molar occlusal microwear texture and anisotropy analyses of 3 Australopithecus anamensis fossil specimens have shown complexity values similar to those of Au. afarensis, indicating that neither of these hominin species had a diet dominated by hard food. However, many researchers have suggested that these were some of the earliest hominins to have such diets. Here we examine buccal microwear patterns of 5 Au. anamensis, 26 Au. afarensis, 48 Hominoidea and 80 Cercopithecoidea primate specimens for independent evidence of dietary adaptations of Au. anamensis. The buccal microwear results obtained suggest that the diet of Au. anamensis relied heavily on hard, brittle food, at least seasonally. This is similar to the diet of the extant Cercopithecoidea primates, including Papio anubis and Chlorocebus aethiops, both of which live in wooded, seasonal savannah environments and have diets that include fruit and grasses, but also underground storage organs (USOs), such as corms or blades, as well as leaves and seeds, and also Mandrillus and Cercocebus, from forested environments with frugivorous-granivorous diets. Furthermore, the buccal microwear patterns of Au. anamensis and Au. afarensis clearly differed-in clear contrast to occlusal enamel texture observations-which support previous dietary interpretations based on both anatomical and palaeocological reconstructions.
American Journal of Physical Anthropology
Anthropologischer Anzeiger
Syria
-Le phénomène de diffusion du Néolithique depuis le Proche-Orient vers l'Europe et son influence ... more -Le phénomène de diffusion du Néolithique depuis le Proche-Orient vers l'Europe et son influence sur la néolithisation de l'Europe a été abordé par diverses disciplines. L'analyse génétique des populations humaines récentes a donné des résultats contradictoires. Tandis que la distribution et les fréquences allele des « marqueurs classiques » (groupes sanguins et protéines), et la variabilité moléculaire du chromosome Y confortent le modèle de diffusion démique, la variabilité de l'ADN mitochondrie nous propose une origine surtout paléolithique des populations européennes actuelles, avec une petite contribution néolithique depuis le Proche-Orient. L'analyse génétique des échantillons biologiques nous permet d'établir cette hypothèse. Dans ce travail, nous avons étudié la variabilité mitochondrial de sept individus du néolithique PPNB de Tell Ramad (Syrie). Les séquences d'ADN mitochondrial obtenues sont très similaires à celles trouvées aujourd'hui en Europe et au Proche-Orient, et elles suggèrent que, dans cette région, il y aurait une continuité génétique depuis le Néolithique.
Journal of Archaeological Science: Reports
Folia primatologica; international journal of primatology, Jan 12, 2018
Vertical clinging is a specialized form of locomotion characteristic of the primate family Callit... more Vertical clinging is a specialized form of locomotion characteristic of the primate family Callitrichidae. Vertical clinging requires these pronograde primates to maintain a vertical posture, so the protraction of their forelimbs must resist gravity. Since pronograde primates usually move as horizontal quadrupeds, we hypothesized that the supraspinatus muscle of vertical clingers would present specific characteristics related to the functional requirements imposed on the shoulder area by vertical clinging. To test this hypothesis, we quantified by real-time quantitative polymerase chain reaction the mRNA transcripts of myosin heavy chain (MHC) isoforms in the supraspinatus muscle of 15 species of pronograde primates, including vertical clingers. Our results indicate that the supraspinatus of vertical clingers has a specific expression pattern of the MHC isoforms, with a low expression of the transcripts of the slow MHC-I isoform and a high expression of the transcripts of the fast M...
PloS one, 2017
Analyses of dental micro- and macro-wear offer valuable information about dietary adaptations. Th... more Analyses of dental micro- and macro-wear offer valuable information about dietary adaptations. The buccal surface of the teeth does not undergo attrition, indicating that dental microwear may directly inform about food properties. Only a few studies have, however, investigated the environmental and individual factors involved in the formation of such microwear in wild animals. Here, we examine variation of buccal microwear patterns of mandibular molars in a large free-ranging population of mandrills (Mandrillus sphinx). We first explore the influence of seasonality and individual's sex, age and tooth macrowear-expressed as the percent of dentine exposure (PDE)-on six microwear variables. Second, we analyze the interplay between individual's diet and PDE. In a last analysis, we revisit our results on mandrills in the light of other primate's microwear studies. We show that the average buccal scratch length and the frequency of vertical buccal scratches are both higher dur...
Archives of oral biology, Jan 9, 2017
The aim of this study is to examine the expression pattern of the different myosin heavy chain (M... more The aim of this study is to examine the expression pattern of the different myosin heavy chain (MyHC) isoforms in the masseter and medial pterygoid muscles by real time quantitative polymerase chain reaction (RT-qPCR) to obtain information at molecular level which can be related to the functional characteristics of these two muscles. The masseter, deep and superficial portion, and medial pterygoid muscles of five adult Pan troglodytes were dissected in order to obtain samples of the anterior and posterior regions of each portion of the masseter and of the medial pterygoid. The expression of MyHC isoforms mRNA transcripts was analyzed by RT-qPCR. No significant differences in expression of MyHC isoforms between the masseter and the medial pterygoid were found. In contrast, when comparing the superficial and the deep portion of the masseter, we found that the MyHC-IIM isoform was expressed at a significantly higher level in the superficial portion. The superficial portion of the masse...