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Jean-jacques Jaeger - One of the best experts on this subject based on the ideXlab platform.
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Late middle Eocene epoch of Libya yields earliest known radiation of African anthropoids
Nature, 2010Co-Authors: Jean-jacques Jaeger, Yaowalak Chaimanee, K. Christopher Beard, Mustafa Salem, Mouloud Benammi, Osama Hlal, Pauline Coster, Awad A. Bilal, Philippe Duringer, Mathieu SchusterAbstract:Reconstructing the early evolutionary history of anthropoid primates is hindered by a lack of consensus on both the timing and biogeography of anthropoid origins^ 1 , 2 , 3 . Some prefer an ancient (Cretaceous) origin for anthropoids in Africa or some other Gondwanan landmass^ 4 , whereas others advocate a more recent (early Cenozoic) origin for anthropoids in Asia^ 1 , 2 , 5 , with subsequent dispersal of one or more early anthropoid taxa to Africa. The oldest undoubted African anthropoid primates described so far are three species of the parapithecid Biretia from the late middle Eocene Bir El Ater locality of Algeria^ 6 and the late Eocene BQ-2 site in the Fayum region of northern Egypt^ 7 . Here we report the discovery of the oldest known diverse assemblage of African anthropoids from the late middle Eocene Dur At-Talah escarpment in central Libya. The primate assemblage from Dur At-Talah includes diminutive species pertaining to three higher-level anthropoid clades (Afrotarsiidae, Parapithecidae and Oligopithecidae) as well as a small species of the early strepsirhine primate Karanisia . The high taxonomic diversity of anthropoids at Dur At-Talah indicates either a much longer interval of anthropoid evolution in Africa than is currently documented in the fossil record or the nearly synchronous colonization of Africa by multiple anthropoid clades at some time during the middle Eocene epoch. The origin of the anthropoids (higher primates, including monkeys, apes and humans) is mysterious. Fossils from the Eocene epoch in Africa have suggested that the anthropoids originated there, but this has been challenged by findings in Asia. Here, the discovery is reported of the oldest known diverse assemblage of African anthropoids, from the Eocene of Libya. The diversity of species found suggests either a long interval of anthropoid evolution in Africa, or the nearly synchronous colonization of Africa by several anthropoid clades. The origin of the anthropoids — higher primates including monkeys, apes and humans — is shrouded in mystery. Fossils from the Eocene of Africa have suggested that they originated in that continent, but this has been challenged by discoveries in Asia. The game is changed by the discovery of several species of anthropoid primate from the Eocene of Libya, each belonging to a distinct group. This suggests that the anthropoids diverged early — possibly in Asia, migrating to Africa along with other kinds of mammal.
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late middle eocene epoch of libya yields earliest known radiation of african anthropoids
Nature, 2010Co-Authors: Jean-jacques Jaeger, Yaowalak Chaimanee, Mouloud Benammi, Osama Hlal, Pauline Coster, Awad A. Bilal, Philippe Duringer, Christopher K Beard, Mustafa J Salem, Mathieu SchusterAbstract:Reconstructing the early evolutionary history of anthropoid primates is hindered by a lack of consensus on both the timing and biogeography of anthropoid origins. Some prefer an ancient (Cretaceous) origin for anthropoids in Africa or some other Gondwanan landmass, whereas others advocate a more recent (early Cenozoic) origin for anthropoids in Asia, with subsequent dispersal of one or more early anthropoid taxa to Africa. The oldest undoubted African anthropoid primates described so far are three species of the parapithecid Biretia from the late middle Eocene Bir El Ater locality of Algeria and the late Eocene BQ-2 site in the Fayum region of northern Egypt. Here we report the discovery of the oldest known diverse assemblage of African anthropoids from the late middle Eocene Dur At-Talah escarpment in central Libya. The primate assemblage from Dur At-Talah includes diminutive species pertaining to three higher-level anthropoid clades (Afrotarsiidae, Parapithecidae and Oligopithecidae) as well as a small species of the early strepsirhine primate Karanisia. The high taxonomic diversity of anthropoids at Dur At-Talah indicates either a much longer interval of anthropoid evolution in Africa than is currently documented in the fossil record or the nearly synchronous colonization of Africa by multiple anthropoid clades at some time during the middle Eocene epoch.
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The face of Siamopithecus: new geometric-morphometric evidence for its anthropoid status.
Anatomical Record-advances in Integrative Anatomy and Evolutionary Biology, 2009Co-Authors: Christoph P. E. Zollikofer, Yaowalak Chaimanee, Renaud Lebrun, Marcia S. Ponce De León, Paul Tafforeau, Sasidhorn Khansubhaand, Jean-jacques JaegerAbstract:Amphipithecids assume a key position in early primate evolution in Asia. Here we report on new maxillofacial and associated mandibular remains of Siamopithecus eocaenus, an amphipithecid primate from the Late Eocene of Krabi (Thailand) that currently represents the most complete specimen belonging to this group. We used synchrotron microtomography and techniques of virtual reconstruction to recover the three-dimensional morphology of the specimen. Geometric-morphometric analysis of the reconstructed specimen within a comparative sample of recent and fossil primates clearly associates Siamopithecus with the anthropoids. Like modern anthropoids, Siamopithecus displays a relatively short face and highly convergent and frontated orbits, the lower rim of which lies well above the alveolar plane. The cooccurrence of spatially correlated anthropoid features and classical anthropoid dental characters in one individual represents a strong argument to support the anthropoid status of Siamopithecus. It is, thus, highly unlikely that amphipithecids are specialized adapiforms exhibiting complete convergence with anthropoids.
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the anthropoid status of a primate from the late middle eocene pondaung formation central myanmar tarsal evidence
Proceedings of the National Academy of Sciences of the United States of America, 2003Co-Authors: Laurent Marivaux, Stéphane Ducrocq, Yaowalak Chaimanee, Bernard Marandat, Jean Sudre, Wanna Htoon, Jean-jacques JaegerAbstract:Primate dental and postcranial remains from the Eocene Pondaung Formation (Myanmar) have been the subject of considerable confusion since their initial discoveries, and their anthropoid status has been widely debated. We report here a well preserved primate talus discovered in the Segyauk locality near Mogaung that displays derived anatomical features typical of haplorhines, notably anthropoids, and lacks strepsirhine synapomorphies. Linear discriminant and parsimony analyses indicate that the talus from Myanmar is more similar structurally to those of living and extinct anthropoids than to those of adapiforms, and its overall osteological characteristics further point to arboreal quadrupedalism. Regressions of talar dimensions versus body mass in living primates indicate that this foot bone might have belonged to Amphipithecus. This evidence supports hypotheses favoring anthropoid affinities for the large-bodied primates from Pondaung and runs contrary to the hypothesis that Pondaungia and Amphipithecus are strepsirhine adapiforms.
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a lower jaw of pondaungia cotteri from the late middle eocene pondaung formation myanmar confirms its anthropoid status
Proceedings of the National Academy of Sciences of the United States of America, 2000Co-Authors: Yaowalak Chaimanee, Stéphane Ducrocq, Mouloud Benammi, Thit Lwin, Tin Thein, Jean-jacques JaegerAbstract:Pondaungia cotteri is the largest primate known from the Late Middle Eocene Pondaung Formation, Myanmar. Its taxonomic status has been the subject of much debate because of the fragmentary nature of its remains. Initially described as an anthropoid, some authors recently have associated it with adapid primates. These debates have been fueled not only by the incompleteness of the fossils attributed to Pondaungia but also by the reticence of many authors to regard Asia as an important evolutionary theater for Eocene anthropoids. During the November 1998 Myanmar-French Pondaung Expedition, a right lower jaw was discovered that yields the most nearly complete dentition of Pondaungia cotteri ever found: it shows the complete horizontal ramus, alveoli for the second incisor and canine, three premolars, and three molars. The symphysis showed all characteristics of anthropoids but was unfused. The canine root is large, the first premolar is absent, and the second premolar is single-rooted, reduced, and oblique in the tooth row, as in anthropoids. The premolars show a reduced mesio-distal length compared with the tooth row, and their morphology is very similar to that of Amphipithecus mogaungensis. Therefore, the two Pondaung taxa appear to be closely related to each other, with Siamopithecus as their sister taxon.
Yaowalak Chaimanee - One of the best experts on this subject based on the ideXlab platform.
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late middle eocene primate from myanmar and the initial anthropoid colonization of africa
Proceedings of the National Academy of Sciences of the United States of America, 2012Co-Authors: Yaowalak Chaimanee, Laurent Marivaux, Christopher K Beard, Olivier Chavasseau, Aung Aung Kyaw, Chit Sein, Vincent Lazzari, Bernard Marandat, Mana Rugbumrung, Thit LwinAbstract:Reconstructing the origin and early evolutionary history of anthropoid primates (monkeys, apes, and humans) is a current focus of paleoprimatology. Although earlier hypotheses frequently supported an African origin for anthropoids, recent discoveries of older and phylogenetically more basal fossils in China and Myanmar indicate that the group originated in Asia. Given the Oligocene-Recent history of African anthropoids, the colonization of Africa by early anthropoids hailing from Asia was a decisive event in primate evolution. However, the fossil record has so far failed to constrain the nature and timing of this pivotal event. Here we describe a fossil primate from the late middle Eocene Pondaung Formation of Myanmar, Afrasia djijidae gen. et sp. nov., that is remarkably similar to, yet dentally more primitive than, the roughly contemporaneous North African anthropoid Afrotarsius. Phylogenetic analysis suggests that Afrasia and Afrotarsius are sister taxa within a basal anthropoid clade designated as the infraorder Eosimiiformes. Current knowledge of eosimiiform relationships and their distribution through space and time suggests that members of this clade dispersed from Asia to Africa sometime during the middle Eocene, shortly before their first appearance in the African fossil record. Crown anthropoids and their nearest fossil relatives do not appear to be specially related to Afrotarsius, suggesting one or more additional episodes of dispersal from Asia to Africa. Hystricognathous rodents, anthracotheres, and possibly other Asian mammal groups seem to have colonized Africa at roughly the same time or shortly after anthropoids gained their first toehold there.
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Late middle Eocene epoch of Libya yields earliest known radiation of African anthropoids
Nature, 2010Co-Authors: Jean-jacques Jaeger, Yaowalak Chaimanee, K. Christopher Beard, Mustafa Salem, Mouloud Benammi, Osama Hlal, Pauline Coster, Awad A. Bilal, Philippe Duringer, Mathieu SchusterAbstract:Reconstructing the early evolutionary history of anthropoid primates is hindered by a lack of consensus on both the timing and biogeography of anthropoid origins^ 1 , 2 , 3 . Some prefer an ancient (Cretaceous) origin for anthropoids in Africa or some other Gondwanan landmass^ 4 , whereas others advocate a more recent (early Cenozoic) origin for anthropoids in Asia^ 1 , 2 , 5 , with subsequent dispersal of one or more early anthropoid taxa to Africa. The oldest undoubted African anthropoid primates described so far are three species of the parapithecid Biretia from the late middle Eocene Bir El Ater locality of Algeria^ 6 and the late Eocene BQ-2 site in the Fayum region of northern Egypt^ 7 . Here we report the discovery of the oldest known diverse assemblage of African anthropoids from the late middle Eocene Dur At-Talah escarpment in central Libya. The primate assemblage from Dur At-Talah includes diminutive species pertaining to three higher-level anthropoid clades (Afrotarsiidae, Parapithecidae and Oligopithecidae) as well as a small species of the early strepsirhine primate Karanisia . The high taxonomic diversity of anthropoids at Dur At-Talah indicates either a much longer interval of anthropoid evolution in Africa than is currently documented in the fossil record or the nearly synchronous colonization of Africa by multiple anthropoid clades at some time during the middle Eocene epoch. The origin of the anthropoids (higher primates, including monkeys, apes and humans) is mysterious. Fossils from the Eocene epoch in Africa have suggested that the anthropoids originated there, but this has been challenged by findings in Asia. Here, the discovery is reported of the oldest known diverse assemblage of African anthropoids, from the Eocene of Libya. The diversity of species found suggests either a long interval of anthropoid evolution in Africa, or the nearly synchronous colonization of Africa by several anthropoid clades. The origin of the anthropoids — higher primates including monkeys, apes and humans — is shrouded in mystery. Fossils from the Eocene of Africa have suggested that they originated in that continent, but this has been challenged by discoveries in Asia. The game is changed by the discovery of several species of anthropoid primate from the Eocene of Libya, each belonging to a distinct group. This suggests that the anthropoids diverged early — possibly in Asia, migrating to Africa along with other kinds of mammal.
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late middle eocene epoch of libya yields earliest known radiation of african anthropoids
Nature, 2010Co-Authors: Jean-jacques Jaeger, Yaowalak Chaimanee, Mouloud Benammi, Osama Hlal, Pauline Coster, Awad A. Bilal, Philippe Duringer, Christopher K Beard, Mustafa J Salem, Mathieu SchusterAbstract:Reconstructing the early evolutionary history of anthropoid primates is hindered by a lack of consensus on both the timing and biogeography of anthropoid origins. Some prefer an ancient (Cretaceous) origin for anthropoids in Africa or some other Gondwanan landmass, whereas others advocate a more recent (early Cenozoic) origin for anthropoids in Asia, with subsequent dispersal of one or more early anthropoid taxa to Africa. The oldest undoubted African anthropoid primates described so far are three species of the parapithecid Biretia from the late middle Eocene Bir El Ater locality of Algeria and the late Eocene BQ-2 site in the Fayum region of northern Egypt. Here we report the discovery of the oldest known diverse assemblage of African anthropoids from the late middle Eocene Dur At-Talah escarpment in central Libya. The primate assemblage from Dur At-Talah includes diminutive species pertaining to three higher-level anthropoid clades (Afrotarsiidae, Parapithecidae and Oligopithecidae) as well as a small species of the early strepsirhine primate Karanisia. The high taxonomic diversity of anthropoids at Dur At-Talah indicates either a much longer interval of anthropoid evolution in Africa than is currently documented in the fossil record or the nearly synchronous colonization of Africa by multiple anthropoid clades at some time during the middle Eocene epoch.
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The face of Siamopithecus: new geometric-morphometric evidence for its anthropoid status.
Anatomical Record-advances in Integrative Anatomy and Evolutionary Biology, 2009Co-Authors: Christoph P. E. Zollikofer, Yaowalak Chaimanee, Renaud Lebrun, Marcia S. Ponce De León, Paul Tafforeau, Sasidhorn Khansubhaand, Jean-jacques JaegerAbstract:Amphipithecids assume a key position in early primate evolution in Asia. Here we report on new maxillofacial and associated mandibular remains of Siamopithecus eocaenus, an amphipithecid primate from the Late Eocene of Krabi (Thailand) that currently represents the most complete specimen belonging to this group. We used synchrotron microtomography and techniques of virtual reconstruction to recover the three-dimensional morphology of the specimen. Geometric-morphometric analysis of the reconstructed specimen within a comparative sample of recent and fossil primates clearly associates Siamopithecus with the anthropoids. Like modern anthropoids, Siamopithecus displays a relatively short face and highly convergent and frontated orbits, the lower rim of which lies well above the alveolar plane. The cooccurrence of spatially correlated anthropoid features and classical anthropoid dental characters in one individual represents a strong argument to support the anthropoid status of Siamopithecus. It is, thus, highly unlikely that amphipithecids are specialized adapiforms exhibiting complete convergence with anthropoids.
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the anthropoid status of a primate from the late middle eocene pondaung formation central myanmar tarsal evidence
Proceedings of the National Academy of Sciences of the United States of America, 2003Co-Authors: Laurent Marivaux, Stéphane Ducrocq, Yaowalak Chaimanee, Bernard Marandat, Jean Sudre, Wanna Htoon, Jean-jacques JaegerAbstract:Primate dental and postcranial remains from the Eocene Pondaung Formation (Myanmar) have been the subject of considerable confusion since their initial discoveries, and their anthropoid status has been widely debated. We report here a well preserved primate talus discovered in the Segyauk locality near Mogaung that displays derived anatomical features typical of haplorhines, notably anthropoids, and lacks strepsirhine synapomorphies. Linear discriminant and parsimony analyses indicate that the talus from Myanmar is more similar structurally to those of living and extinct anthropoids than to those of adapiforms, and its overall osteological characteristics further point to arboreal quadrupedalism. Regressions of talar dimensions versus body mass in living primates indicate that this foot bone might have belonged to Amphipithecus. This evidence supports hypotheses favoring anthropoid affinities for the large-bodied primates from Pondaung and runs contrary to the hypothesis that Pondaungia and Amphipithecus are strepsirhine adapiforms.
Stéphane Ducrocq - One of the best experts on this subject based on the ideXlab platform.
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the anthropoid status of a primate from the late middle eocene pondaung formation central myanmar tarsal evidence
Proceedings of the National Academy of Sciences of the United States of America, 2003Co-Authors: Laurent Marivaux, Stéphane Ducrocq, Yaowalak Chaimanee, Bernard Marandat, Jean Sudre, Wanna Htoon, Jean-jacques JaegerAbstract:Primate dental and postcranial remains from the Eocene Pondaung Formation (Myanmar) have been the subject of considerable confusion since their initial discoveries, and their anthropoid status has been widely debated. We report here a well preserved primate talus discovered in the Segyauk locality near Mogaung that displays derived anatomical features typical of haplorhines, notably anthropoids, and lacks strepsirhine synapomorphies. Linear discriminant and parsimony analyses indicate that the talus from Myanmar is more similar structurally to those of living and extinct anthropoids than to those of adapiforms, and its overall osteological characteristics further point to arboreal quadrupedalism. Regressions of talar dimensions versus body mass in living primates indicate that this foot bone might have belonged to Amphipithecus. This evidence supports hypotheses favoring anthropoid affinities for the large-bodied primates from Pondaung and runs contrary to the hypothesis that Pondaungia and Amphipithecus are strepsirhine adapiforms.
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a lower jaw of pondaungia cotteri from the late middle eocene pondaung formation myanmar confirms its anthropoid status
Proceedings of the National Academy of Sciences of the United States of America, 2000Co-Authors: Yaowalak Chaimanee, Stéphane Ducrocq, Mouloud Benammi, Thit Lwin, Tin Thein, Jean-jacques JaegerAbstract:Pondaungia cotteri is the largest primate known from the Late Middle Eocene Pondaung Formation, Myanmar. Its taxonomic status has been the subject of much debate because of the fragmentary nature of its remains. Initially described as an anthropoid, some authors recently have associated it with adapid primates. These debates have been fueled not only by the incompleteness of the fossils attributed to Pondaungia but also by the reticence of many authors to regard Asia as an important evolutionary theater for Eocene anthropoids. During the November 1998 Myanmar-French Pondaung Expedition, a right lower jaw was discovered that yields the most nearly complete dentition of Pondaungia cotteri ever found: it shows the complete horizontal ramus, alveoli for the second incisor and canine, three premolars, and three molars. The symphysis showed all characteristics of anthropoids but was unfused. The canine root is large, the first premolar is absent, and the second premolar is single-rooted, reduced, and oblique in the tooth row, as in anthropoids. The premolars show a reduced mesio-distal length compared with the tooth row, and their morphology is very similar to that of Amphipithecus mogaungensis. Therefore, the two Pondaung taxa appear to be closely related to each other, with Siamopithecus as their sister taxon.
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A New Primate from the Middle Eocene of Myanmar and the Asian Early Origin of Anthropoids
Science, 1999Co-Authors: Jean-jacques Jaeger, Yaowalak Chaimanee, Mouloud Benammi, Thit Lwin, Tin Thein, Stéphane DucrocqAbstract:A new genus and species of anthropoid primate, Bahinia pondaungensis gen. et sp. nov., is described from the Yashe Kyitchaung locality in the Late Middle Eocene Pondaung Formation (Myanmar). It is related to Eosimias , but it is represented by more complete remains, including upper dentition with associated lower jaw fragment. It is interpreted as a new representative of the family Eosimiidae, which corresponds to the sister group of the Amphipithecidae and of all other anthropoids. Eosimiidae are now recorded from three distinct Middle Eocene localities in Asia, giving support to the hypothesis of an Asian origin of anthropoids.
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a new late eocene anthropoid primate from thailand
Nature, 1997Co-Authors: Yaowalak Chaimanee, Varavudh Suteethorn, Jean-jacques Jaeger, Stéphane DucrocqAbstract:The fossil record of anthropoid primates from the Middle Eocene of South Asia is so far restricted to two genera (Pondaungia cotteri Pilgrim, 1937 and Amphipithecus mogaungensis Colbert, 1937 from the Eocene Pondaung deposits of Burma) whose anthropoid status and phylogenetic position have long been under debate,1–6 because they represent the oldest highly derived fossil primates of anthropoid grade. Moreover, several new African taxa7–10, some of which are even older, have been recently included in the suborder Anthropoidea, suggesting an African origin for this group. Conversely, new fossil primates recently discovered in China (Eosimias) have been related to the most primitive representatives of Anthropoidea, alternatively suggesting an Asian origin and a probable Asian radiation centre11. We report here the discovery of a new anthropoid from the Thai Late Eocene locality of Krabi12,13, which displays several additional anthropoid characters with regard to those of the Eocene Burmese genera. This species, which is about the size of the Fayum Aegyptopithecus, can be related to the Burmese forms, and it further provides strong additional evidence for a southeast Asian evolutionary centre for anthropoids.
Thit Lwin - One of the best experts on this subject based on the ideXlab platform.
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late middle eocene primate from myanmar and the initial anthropoid colonization of africa
Proceedings of the National Academy of Sciences of the United States of America, 2012Co-Authors: Yaowalak Chaimanee, Laurent Marivaux, Christopher K Beard, Olivier Chavasseau, Aung Aung Kyaw, Chit Sein, Vincent Lazzari, Bernard Marandat, Mana Rugbumrung, Thit LwinAbstract:Reconstructing the origin and early evolutionary history of anthropoid primates (monkeys, apes, and humans) is a current focus of paleoprimatology. Although earlier hypotheses frequently supported an African origin for anthropoids, recent discoveries of older and phylogenetically more basal fossils in China and Myanmar indicate that the group originated in Asia. Given the Oligocene-Recent history of African anthropoids, the colonization of Africa by early anthropoids hailing from Asia was a decisive event in primate evolution. However, the fossil record has so far failed to constrain the nature and timing of this pivotal event. Here we describe a fossil primate from the late middle Eocene Pondaung Formation of Myanmar, Afrasia djijidae gen. et sp. nov., that is remarkably similar to, yet dentally more primitive than, the roughly contemporaneous North African anthropoid Afrotarsius. Phylogenetic analysis suggests that Afrasia and Afrotarsius are sister taxa within a basal anthropoid clade designated as the infraorder Eosimiiformes. Current knowledge of eosimiiform relationships and their distribution through space and time suggests that members of this clade dispersed from Asia to Africa sometime during the middle Eocene, shortly before their first appearance in the African fossil record. Crown anthropoids and their nearest fossil relatives do not appear to be specially related to Afrotarsius, suggesting one or more additional episodes of dispersal from Asia to Africa. Hystricognathous rodents, anthracotheres, and possibly other Asian mammal groups seem to have colonized Africa at roughly the same time or shortly after anthropoids gained their first toehold there.
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a lower jaw of pondaungia cotteri from the late middle eocene pondaung formation myanmar confirms its anthropoid status
Proceedings of the National Academy of Sciences of the United States of America, 2000Co-Authors: Yaowalak Chaimanee, Stéphane Ducrocq, Mouloud Benammi, Thit Lwin, Tin Thein, Jean-jacques JaegerAbstract:Pondaungia cotteri is the largest primate known from the Late Middle Eocene Pondaung Formation, Myanmar. Its taxonomic status has been the subject of much debate because of the fragmentary nature of its remains. Initially described as an anthropoid, some authors recently have associated it with adapid primates. These debates have been fueled not only by the incompleteness of the fossils attributed to Pondaungia but also by the reticence of many authors to regard Asia as an important evolutionary theater for Eocene anthropoids. During the November 1998 Myanmar-French Pondaung Expedition, a right lower jaw was discovered that yields the most nearly complete dentition of Pondaungia cotteri ever found: it shows the complete horizontal ramus, alveoli for the second incisor and canine, three premolars, and three molars. The symphysis showed all characteristics of anthropoids but was unfused. The canine root is large, the first premolar is absent, and the second premolar is single-rooted, reduced, and oblique in the tooth row, as in anthropoids. The premolars show a reduced mesio-distal length compared with the tooth row, and their morphology is very similar to that of Amphipithecus mogaungensis. Therefore, the two Pondaung taxa appear to be closely related to each other, with Siamopithecus as their sister taxon.
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A New Primate from the Middle Eocene of Myanmar and the Asian Early Origin of Anthropoids
Science, 1999Co-Authors: Jean-jacques Jaeger, Yaowalak Chaimanee, Mouloud Benammi, Thit Lwin, Tin Thein, Stéphane DucrocqAbstract:A new genus and species of anthropoid primate, Bahinia pondaungensis gen. et sp. nov., is described from the Yashe Kyitchaung locality in the Late Middle Eocene Pondaung Formation (Myanmar). It is related to Eosimias , but it is represented by more complete remains, including upper dentition with associated lower jaw fragment. It is interpreted as a new representative of the family Eosimiidae, which corresponds to the sister group of the Amphipithecidae and of all other anthropoids. Eosimiidae are now recorded from three distinct Middle Eocene localities in Asia, giving support to the hypothesis of an Asian origin of anthropoids.
Mouloud Benammi - One of the best experts on this subject based on the ideXlab platform.
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Late middle Eocene epoch of Libya yields earliest known radiation of African anthropoids
Nature, 2010Co-Authors: Jean-jacques Jaeger, Yaowalak Chaimanee, K. Christopher Beard, Mustafa Salem, Mouloud Benammi, Osama Hlal, Pauline Coster, Awad A. Bilal, Philippe Duringer, Mathieu SchusterAbstract:Reconstructing the early evolutionary history of anthropoid primates is hindered by a lack of consensus on both the timing and biogeography of anthropoid origins^ 1 , 2 , 3 . Some prefer an ancient (Cretaceous) origin for anthropoids in Africa or some other Gondwanan landmass^ 4 , whereas others advocate a more recent (early Cenozoic) origin for anthropoids in Asia^ 1 , 2 , 5 , with subsequent dispersal of one or more early anthropoid taxa to Africa. The oldest undoubted African anthropoid primates described so far are three species of the parapithecid Biretia from the late middle Eocene Bir El Ater locality of Algeria^ 6 and the late Eocene BQ-2 site in the Fayum region of northern Egypt^ 7 . Here we report the discovery of the oldest known diverse assemblage of African anthropoids from the late middle Eocene Dur At-Talah escarpment in central Libya. The primate assemblage from Dur At-Talah includes diminutive species pertaining to three higher-level anthropoid clades (Afrotarsiidae, Parapithecidae and Oligopithecidae) as well as a small species of the early strepsirhine primate Karanisia . The high taxonomic diversity of anthropoids at Dur At-Talah indicates either a much longer interval of anthropoid evolution in Africa than is currently documented in the fossil record or the nearly synchronous colonization of Africa by multiple anthropoid clades at some time during the middle Eocene epoch. The origin of the anthropoids (higher primates, including monkeys, apes and humans) is mysterious. Fossils from the Eocene epoch in Africa have suggested that the anthropoids originated there, but this has been challenged by findings in Asia. Here, the discovery is reported of the oldest known diverse assemblage of African anthropoids, from the Eocene of Libya. The diversity of species found suggests either a long interval of anthropoid evolution in Africa, or the nearly synchronous colonization of Africa by several anthropoid clades. The origin of the anthropoids — higher primates including monkeys, apes and humans — is shrouded in mystery. Fossils from the Eocene of Africa have suggested that they originated in that continent, but this has been challenged by discoveries in Asia. The game is changed by the discovery of several species of anthropoid primate from the Eocene of Libya, each belonging to a distinct group. This suggests that the anthropoids diverged early — possibly in Asia, migrating to Africa along with other kinds of mammal.
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late middle eocene epoch of libya yields earliest known radiation of african anthropoids
Nature, 2010Co-Authors: Jean-jacques Jaeger, Yaowalak Chaimanee, Mouloud Benammi, Osama Hlal, Pauline Coster, Awad A. Bilal, Philippe Duringer, Christopher K Beard, Mustafa J Salem, Mathieu SchusterAbstract:Reconstructing the early evolutionary history of anthropoid primates is hindered by a lack of consensus on both the timing and biogeography of anthropoid origins. Some prefer an ancient (Cretaceous) origin for anthropoids in Africa or some other Gondwanan landmass, whereas others advocate a more recent (early Cenozoic) origin for anthropoids in Asia, with subsequent dispersal of one or more early anthropoid taxa to Africa. The oldest undoubted African anthropoid primates described so far are three species of the parapithecid Biretia from the late middle Eocene Bir El Ater locality of Algeria and the late Eocene BQ-2 site in the Fayum region of northern Egypt. Here we report the discovery of the oldest known diverse assemblage of African anthropoids from the late middle Eocene Dur At-Talah escarpment in central Libya. The primate assemblage from Dur At-Talah includes diminutive species pertaining to three higher-level anthropoid clades (Afrotarsiidae, Parapithecidae and Oligopithecidae) as well as a small species of the early strepsirhine primate Karanisia. The high taxonomic diversity of anthropoids at Dur At-Talah indicates either a much longer interval of anthropoid evolution in Africa than is currently documented in the fossil record or the nearly synchronous colonization of Africa by multiple anthropoid clades at some time during the middle Eocene epoch.
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a lower jaw of pondaungia cotteri from the late middle eocene pondaung formation myanmar confirms its anthropoid status
Proceedings of the National Academy of Sciences of the United States of America, 2000Co-Authors: Yaowalak Chaimanee, Stéphane Ducrocq, Mouloud Benammi, Thit Lwin, Tin Thein, Jean-jacques JaegerAbstract:Pondaungia cotteri is the largest primate known from the Late Middle Eocene Pondaung Formation, Myanmar. Its taxonomic status has been the subject of much debate because of the fragmentary nature of its remains. Initially described as an anthropoid, some authors recently have associated it with adapid primates. These debates have been fueled not only by the incompleteness of the fossils attributed to Pondaungia but also by the reticence of many authors to regard Asia as an important evolutionary theater for Eocene anthropoids. During the November 1998 Myanmar-French Pondaung Expedition, a right lower jaw was discovered that yields the most nearly complete dentition of Pondaungia cotteri ever found: it shows the complete horizontal ramus, alveoli for the second incisor and canine, three premolars, and three molars. The symphysis showed all characteristics of anthropoids but was unfused. The canine root is large, the first premolar is absent, and the second premolar is single-rooted, reduced, and oblique in the tooth row, as in anthropoids. The premolars show a reduced mesio-distal length compared with the tooth row, and their morphology is very similar to that of Amphipithecus mogaungensis. Therefore, the two Pondaung taxa appear to be closely related to each other, with Siamopithecus as their sister taxon.
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A New Primate from the Middle Eocene of Myanmar and the Asian Early Origin of Anthropoids
Science, 1999Co-Authors: Jean-jacques Jaeger, Yaowalak Chaimanee, Mouloud Benammi, Thit Lwin, Tin Thein, Stéphane DucrocqAbstract:A new genus and species of anthropoid primate, Bahinia pondaungensis gen. et sp. nov., is described from the Yashe Kyitchaung locality in the Late Middle Eocene Pondaung Formation (Myanmar). It is related to Eosimias , but it is represented by more complete remains, including upper dentition with associated lower jaw fragment. It is interpreted as a new representative of the family Eosimiidae, which corresponds to the sister group of the Amphipithecidae and of all other anthropoids. Eosimiidae are now recorded from three distinct Middle Eocene localities in Asia, giving support to the hypothesis of an Asian origin of anthropoids.
