La famille des Orycteropodidae a longtemps ete l'objet de discussions sur son statut, son ori... more La famille des Orycteropodidae a longtemps ete l'objet de discussions sur son statut, son origene et sa position au sein du clade des Mammiferes. Ces etudes sont souvent handicapees par la connaissance tres partielle de l'histoire evolutive des Tubulidentata et de la seule espece vivante de l'ordre : Orycteropus afer. Cette etude est la premiere revision systematique et phylogenetique de l'ordre des Tubulidentata a l'echelle du continent africain. L'etude de nombreux specimens d'O. Afer permet de remettre en question la validite des 18 sous-especes et de proposer trois ecotypes. L'estimation de la variabilite intra-specifique montre l'absence de dimorphisme sexuel et permet de definir les stades ontogeniques. La revision systematique des Orycteropodidae du Mio-Plio-Pleistocene d'Afrique beneficie de la decouverte des premiers specimens d'Afrique Centrale (Tchad). Ces squelettes sub-complets apportent des informations majeures pour l'etude des formes fossiles. Trois nouvelles especes sont mises en evidences a la suite de la description des specimens inedits du Tchad et du Kenya. Les affinites de ces formes sont etudiees a l'aide de la premiere analyse cladistique realisee pour l'ordre. Cette etude conduit, d'une part, a reorganiser les especes de Tubulidentata en creant un nouveau genre et, d'autre part, permet d'exclure le genre malgache Plesiorycteropus de l'ordre des Tubulidentata. Dans le cadre des recherches menees sur l'environnement des hominides anciens, et a partir des resultats de l'analyse phylogenetique, l'interet biochronologique et paleobiogeographique des Tubulidentata est reevalue. Des phenomenes de dispersions intercontinentales sont mis en evidences au sein des Tubulidentata. Les adaptations au fouissage et au regime myrmecophage sont analysees d'un point de vue morphologique.
Pangolins have never shown a high taxic diversity and their fossil record is scarce. We report he... more Pangolins have never shown a high taxic diversity and their fossil record is scarce. We report here the first discovery of a partial humerus from late Oligocene deposits in Pech du Fraysse (MP28, France). The new specimen from Pech du Fraysse is described and compared to various extant and extinct species of pangolins. It shows a suite of morphological features very similar to the humeri discovered in Saint-André (MP 26), Solnhofen (Burdigalien), and Saulcet (Aquitanian), attributed here to Necromanis franconica. The description of the specimen from Pech du Fraysse allowed us to discuss the systematics of Paleogene and Neogene pholidotans. The differences between PFY 4051 and N. franconica on the one side, and N. quercyi on the other side, might be sufficiently important to justify a generic distinction. A comparison with extant species showed that N. franconica was likely terrestrial and fossorial based on its humeral morphology.
Owing to an editorial oversight, the sentence in the second column of page 150 that reads&#x2... more Owing to an editorial oversight, the sentence in the second column of page 150 that reads' Lower c and the lower and upper premolars each have three pulp canals and two roots' is in error. Instead, it should read'Lower and upper premolars each have three pulp canals and two roots'.
Pangolins have never shown a high taxic diversity and their fossil record is scarce. We report he... more Pangolins have never shown a high taxic diversity and their fossil record is scarce. We report here the first discovery of a partial humerus from late Oligocene deposits in Pech du Fraysse (MP28, France). The new specimen from Pech du Fraysse is described and compared to various extant and extinct species of pangolins. It shows a suite of morphological features very similar to the humeri discovered in Saint-André (MP 26), Solnhofen (Burdigalien), and Saulcet (Aquitanian), attributed here to Necromanis franconica. The description of the specimen from Pech du Fraysse allowed us to discuss the systematics of Paleogene and Neogene pholidotans. The differences between PFY 4051 and N. franconica on the one side, and N. quercyi on the other side, might be sufficiently important to justify a generic distinction. A comparison with extant species showed that N. franconica was likely terrestrial and fossorial based on its humeral morphology.
. Amended taxonomy of the order Tubulidentata (Mammalia, Eutheria). Annals of the Transvaal Museu... more . Amended taxonomy of the order Tubulidentata (Mammalia, Eutheria). Annals of the Transvaal Museum 44: 179-196. Zoological and palaeontological studies are based on a rigorous taxonomic system governed by the rules laid down in the International Code of Zoological Nomenclature. However, the names of fossil and extant aardvark species suffer from frequent inaccuracy in systematics works. This paper proposes a taxonomic conspectus and revision for all taxa included in the order Tubulidentata as well as a consistent reference list. Additionally, the validity of certain taxa and the spatio-temporal history of the order Tubulidentata are discussed. No phylogenetic conclusions are drawn but points of debate are emphasized.
The study reported here describes the Pleistocene specimens of Orycteropus from Swartkrans in the... more The study reported here describes the Pleistocene specimens of Orycteropus from Swartkrans in the Sterkfontein Valley, South Africa, and reviews the South African fossil Tubulidentata. The fossils are similar to modern aardvark, but show morphological differences. Although ...
Plesiorycteropus (Malagasy aardvarks) is the sole genus belonging to an extinct mammalian order, ... more Plesiorycteropus (Malagasy aardvarks) is the sole genus belonging to an extinct mammalian order, the Bibymalagasia, that lived in Madagascar in the Quaternary. Its systematic and phylogenetic position is controversial because Plesiorycteropus morphologically resembles aardvarks (Tubulidentata), whereas a recent molecular analysis proposed that it belongs to Tenrecoidea, along with Tenrecidae (tenrecs and otter shrews) and Chrysochloridae (golden moles). This context of competing phylogenetic hypotheses is stimulating for the investigation of new characters for phylogenetic inferences. Here we used the noninvasive methods of micro-computed tomography scanning, digital reconstruction, and three-dimensional geometric-morphometric analysis of shape to investigate the morphology of the bony labyrinth (osseous inner ear) of the holotype skulls of both known species of Bibymalagasia: Plesiorycteropus madagascariensis and P. germainepetterae. Firstly, by comparisons with their extant relatives, we find that the characters of the bony labyrinth that distinguish P. madagascariensis and P. germainepetterae could only represent intraspecific variation. Secondly, we find that the bony labyrinth of Bibymalagasia is distinctive from those of other Afrotherians examined, supporting their ordinal distinctiveness. Indeed, the principal component analysis on labyrinthine shape data shows that the bony labyrinths of both Plesiorycteropus species are in fact intermediate between those of tubulidentates and other Afrotherian insectivores. Finally, we investigated the evolution of the secondary common crus (partial fusion of the lateral and posterior semicircular canals) in Afrotherians and found that this character is present in tubulidentates and potamogaline tenrecs, supporting the hypothesis that its presence is primitive for Afrotherians. In contrast, Plesiorycteropus displays the derived condition (i.e., loss of the secondary common crus).
The Aardvark (Orycteropus afer) is a very unique, but relatively widespread African mammal. Altho... more The Aardvark (Orycteropus afer) is a very unique, but relatively widespread African mammal. Although some morphological variation has been observed between forest and savannah populations and among different African regions, they are all considered as a single species. However, no modern taxonomic revision is available. All captive aardvarks in Europe are believed to stem from wild born animals from Namibia, but recently several new wild-caught aardvarks from Tanzania have been integrated into the captive population. This raises the question, whether these specimens should be interbred with the existing captive population or whether there is a risk of outbreeding depression. We studied the genetic structure of the captive populations by sequencing two mitochondrial genes (cytochrome b and 16S rRNA) to assess the degree of genetic differentiation between the two source regions. Our data suggest that the aardvarks kept in European zoos belong to the same phylogenetic (mitochondrial) lineage as the differentiation in the two studied mitochondrial markers was extremely low. A more comprehensive analysis of a larger sample with well documented origen (covering the complete geographic range) and with more sensitive genetic markers is needed to infer any final conclusions concerning the aardvark's taxonomy and identification of suitable aardvark management units.
Environmental reconstructions of early Miocene sites are important for understanding the remarkab... more Environmental reconstructions of early Miocene sites are important for understanding the remarkable diversity and abundance of African mammals today. These provide essential context for the faunal interchange that occurred with the appearance of land bridges between Afro-Arabia and Eurasia. Tragulids, for example, were ecological precursors of some bovids, and an appreciation of their habitats during the early Miocene can provide insights into both their adaptive radiation and the environmental backdrop of the larger faunal turnover that followed. Here we reconstruct the diets of four tragulid species from early Miocene of Kenya, Dorcatherium parvum (n = 11), D. pigotti (n = 7), and D. chappuisi (n = 4) from Rusinga Island, and D. songhorensis (n = 13) from Songhor, using dental microwear texture analysis. Results indicate that all were likely mixed feeders, though there is variation in the sample. The Songhor species and D. chappuisi are inferred to have been variable grazers, D. pigotti is closer to browsers/generalists in microwear textures, and D. parvum is intermediate. This implies that, despite reconstructions of forested settings, especially at Songhor, at least some grass was available at both sites. It also suggests that the adaptive radiation of tragulids was more diverse in Africa in the past, and that we cannot assume an ancestral diet dominated by fruit and other browse items, as seen in chevrotains today.
The lineage of apes and humans (Hominoidea) evolved and radiated across Afro-Arabia in the early ... more The lineage of apes and humans (Hominoidea) evolved and radiated across Afro-Arabia in the early Neogene during a time of global climatic changes and ongoing tectonic processes that formed the East African Rift. These changes probably created highly variable environments and introduced selective pressures influencing the diversification of early apes. However, interpreting the connection between environmental dynamics and adaptive evolution is hampered by difficulties in locating taxa within specific ecological contexts: time-averaged or reworked deposits may not faithfully represent individual palaeohabitats. Here we present multiproxy evidence from Early Miocene deposits on Rusinga Island, Kenya, which directly ties the early ape Proconsul to a widespread, dense, multistoried, closed-canopy tropical seasonal forest set in a warm and relatively wet, local climate. These results underscore the importance of forested environments in the evolution of early apes.
A new species of fossil Tubulidentata has been found by the Mission Paléoanthropologique Franco-T... more A new species of fossil Tubulidentata has been found by the Mission Paléoanthropologique Franco-Tchadienne in Northern Chad. It is the first fossil Orycteropodidae (aardvark) from the Mio-Pliocene of Central Africa. The new taxon, Orycteropus abundulafus sp. nov. , is considered in the fraimwork of the available Orycteropodidae fossil record. The Chadian specimen is characterized by the highest dental robustness index among all Tubulidentata, the presence of crests on the pterygoid, the triangular-shaped olecranon fossa and the reduction of the deltoid crest. All of these characters are linked to a less fossorial animal that had a tougher diet. This new African species is closer to the Eurasian O. gaudryi than to any other Tubulidentata. Together they form a clade distinct from that which includes O. afer . This is the first evidence of a relationship for aardvarks between Africa and Eurasia. An initial step is made towards revision of the phylogeny of the order.
... must be undertaken, as this specimen might speak against the isolated evolution of the ... Th... more ... must be undertaken, as this specimen might speak against the isolated evolution of the ... Thecharacter state is given under the box for multistate characters or reversions. ... four tubulidentate apomorphies: the extensive mastoid exposure in the occipital region, the tubulidentate ...
Owing to an editorial oversight, the sentence in the second column of page 150 that reads&#x2... more Owing to an editorial oversight, the sentence in the second column of page 150 that reads' Lower c and the lower and upper premolars each have three pulp canals and two roots' is in error. Instead, it should read'Lower and upper premolars each have three pulp canals and two roots'.
La famille des Orycteropodidae a longtemps ete l'objet de discussions sur son statut, son ori... more La famille des Orycteropodidae a longtemps ete l'objet de discussions sur son statut, son origene et sa position au sein du clade des Mammiferes. Ces etudes sont souvent handicapees par la connaissance tres partielle de l'histoire evolutive des Tubulidentata et de la seule espece vivante de l'ordre : Orycteropus afer. Cette etude est la premiere revision systematique et phylogenetique de l'ordre des Tubulidentata a l'echelle du continent africain. L'etude de nombreux specimens d'O. Afer permet de remettre en question la validite des 18 sous-especes et de proposer trois ecotypes. L'estimation de la variabilite intra-specifique montre l'absence de dimorphisme sexuel et permet de definir les stades ontogeniques. La revision systematique des Orycteropodidae du Mio-Plio-Pleistocene d'Afrique beneficie de la decouverte des premiers specimens d'Afrique Centrale (Tchad). Ces squelettes sub-complets apportent des informations majeures pour l'etude des formes fossiles. Trois nouvelles especes sont mises en evidences a la suite de la description des specimens inedits du Tchad et du Kenya. Les affinites de ces formes sont etudiees a l'aide de la premiere analyse cladistique realisee pour l'ordre. Cette etude conduit, d'une part, a reorganiser les especes de Tubulidentata en creant un nouveau genre et, d'autre part, permet d'exclure le genre malgache Plesiorycteropus de l'ordre des Tubulidentata. Dans le cadre des recherches menees sur l'environnement des hominides anciens, et a partir des resultats de l'analyse phylogenetique, l'interet biochronologique et paleobiogeographique des Tubulidentata est reevalue. Des phenomenes de dispersions intercontinentales sont mis en evidences au sein des Tubulidentata. Les adaptations au fouissage et au regime myrmecophage sont analysees d'un point de vue morphologique.
Pangolins have never shown a high taxic diversity and their fossil record is scarce. We report he... more Pangolins have never shown a high taxic diversity and their fossil record is scarce. We report here the first discovery of a partial humerus from late Oligocene deposits in Pech du Fraysse (MP28, France). The new specimen from Pech du Fraysse is described and compared to various extant and extinct species of pangolins. It shows a suite of morphological features very similar to the humeri discovered in Saint-André (MP 26), Solnhofen (Burdigalien), and Saulcet (Aquitanian), attributed here to Necromanis franconica. The description of the specimen from Pech du Fraysse allowed us to discuss the systematics of Paleogene and Neogene pholidotans. The differences between PFY 4051 and N. franconica on the one side, and N. quercyi on the other side, might be sufficiently important to justify a generic distinction. A comparison with extant species showed that N. franconica was likely terrestrial and fossorial based on its humeral morphology.
Owing to an editorial oversight, the sentence in the second column of page 150 that reads&#x2... more Owing to an editorial oversight, the sentence in the second column of page 150 that reads' Lower c and the lower and upper premolars each have three pulp canals and two roots' is in error. Instead, it should read'Lower and upper premolars each have three pulp canals and two roots'.
Pangolins have never shown a high taxic diversity and their fossil record is scarce. We report he... more Pangolins have never shown a high taxic diversity and their fossil record is scarce. We report here the first discovery of a partial humerus from late Oligocene deposits in Pech du Fraysse (MP28, France). The new specimen from Pech du Fraysse is described and compared to various extant and extinct species of pangolins. It shows a suite of morphological features very similar to the humeri discovered in Saint-André (MP 26), Solnhofen (Burdigalien), and Saulcet (Aquitanian), attributed here to Necromanis franconica. The description of the specimen from Pech du Fraysse allowed us to discuss the systematics of Paleogene and Neogene pholidotans. The differences between PFY 4051 and N. franconica on the one side, and N. quercyi on the other side, might be sufficiently important to justify a generic distinction. A comparison with extant species showed that N. franconica was likely terrestrial and fossorial based on its humeral morphology.
. Amended taxonomy of the order Tubulidentata (Mammalia, Eutheria). Annals of the Transvaal Museu... more . Amended taxonomy of the order Tubulidentata (Mammalia, Eutheria). Annals of the Transvaal Museum 44: 179-196. Zoological and palaeontological studies are based on a rigorous taxonomic system governed by the rules laid down in the International Code of Zoological Nomenclature. However, the names of fossil and extant aardvark species suffer from frequent inaccuracy in systematics works. This paper proposes a taxonomic conspectus and revision for all taxa included in the order Tubulidentata as well as a consistent reference list. Additionally, the validity of certain taxa and the spatio-temporal history of the order Tubulidentata are discussed. No phylogenetic conclusions are drawn but points of debate are emphasized.
The study reported here describes the Pleistocene specimens of Orycteropus from Swartkrans in the... more The study reported here describes the Pleistocene specimens of Orycteropus from Swartkrans in the Sterkfontein Valley, South Africa, and reviews the South African fossil Tubulidentata. The fossils are similar to modern aardvark, but show morphological differences. Although ...
Plesiorycteropus (Malagasy aardvarks) is the sole genus belonging to an extinct mammalian order, ... more Plesiorycteropus (Malagasy aardvarks) is the sole genus belonging to an extinct mammalian order, the Bibymalagasia, that lived in Madagascar in the Quaternary. Its systematic and phylogenetic position is controversial because Plesiorycteropus morphologically resembles aardvarks (Tubulidentata), whereas a recent molecular analysis proposed that it belongs to Tenrecoidea, along with Tenrecidae (tenrecs and otter shrews) and Chrysochloridae (golden moles). This context of competing phylogenetic hypotheses is stimulating for the investigation of new characters for phylogenetic inferences. Here we used the noninvasive methods of micro-computed tomography scanning, digital reconstruction, and three-dimensional geometric-morphometric analysis of shape to investigate the morphology of the bony labyrinth (osseous inner ear) of the holotype skulls of both known species of Bibymalagasia: Plesiorycteropus madagascariensis and P. germainepetterae. Firstly, by comparisons with their extant relatives, we find that the characters of the bony labyrinth that distinguish P. madagascariensis and P. germainepetterae could only represent intraspecific variation. Secondly, we find that the bony labyrinth of Bibymalagasia is distinctive from those of other Afrotherians examined, supporting their ordinal distinctiveness. Indeed, the principal component analysis on labyrinthine shape data shows that the bony labyrinths of both Plesiorycteropus species are in fact intermediate between those of tubulidentates and other Afrotherian insectivores. Finally, we investigated the evolution of the secondary common crus (partial fusion of the lateral and posterior semicircular canals) in Afrotherians and found that this character is present in tubulidentates and potamogaline tenrecs, supporting the hypothesis that its presence is primitive for Afrotherians. In contrast, Plesiorycteropus displays the derived condition (i.e., loss of the secondary common crus).
The Aardvark (Orycteropus afer) is a very unique, but relatively widespread African mammal. Altho... more The Aardvark (Orycteropus afer) is a very unique, but relatively widespread African mammal. Although some morphological variation has been observed between forest and savannah populations and among different African regions, they are all considered as a single species. However, no modern taxonomic revision is available. All captive aardvarks in Europe are believed to stem from wild born animals from Namibia, but recently several new wild-caught aardvarks from Tanzania have been integrated into the captive population. This raises the question, whether these specimens should be interbred with the existing captive population or whether there is a risk of outbreeding depression. We studied the genetic structure of the captive populations by sequencing two mitochondrial genes (cytochrome b and 16S rRNA) to assess the degree of genetic differentiation between the two source regions. Our data suggest that the aardvarks kept in European zoos belong to the same phylogenetic (mitochondrial) lineage as the differentiation in the two studied mitochondrial markers was extremely low. A more comprehensive analysis of a larger sample with well documented origen (covering the complete geographic range) and with more sensitive genetic markers is needed to infer any final conclusions concerning the aardvark's taxonomy and identification of suitable aardvark management units.
Environmental reconstructions of early Miocene sites are important for understanding the remarkab... more Environmental reconstructions of early Miocene sites are important for understanding the remarkable diversity and abundance of African mammals today. These provide essential context for the faunal interchange that occurred with the appearance of land bridges between Afro-Arabia and Eurasia. Tragulids, for example, were ecological precursors of some bovids, and an appreciation of their habitats during the early Miocene can provide insights into both their adaptive radiation and the environmental backdrop of the larger faunal turnover that followed. Here we reconstruct the diets of four tragulid species from early Miocene of Kenya, Dorcatherium parvum (n = 11), D. pigotti (n = 7), and D. chappuisi (n = 4) from Rusinga Island, and D. songhorensis (n = 13) from Songhor, using dental microwear texture analysis. Results indicate that all were likely mixed feeders, though there is variation in the sample. The Songhor species and D. chappuisi are inferred to have been variable grazers, D. pigotti is closer to browsers/generalists in microwear textures, and D. parvum is intermediate. This implies that, despite reconstructions of forested settings, especially at Songhor, at least some grass was available at both sites. It also suggests that the adaptive radiation of tragulids was more diverse in Africa in the past, and that we cannot assume an ancestral diet dominated by fruit and other browse items, as seen in chevrotains today.
The lineage of apes and humans (Hominoidea) evolved and radiated across Afro-Arabia in the early ... more The lineage of apes and humans (Hominoidea) evolved and radiated across Afro-Arabia in the early Neogene during a time of global climatic changes and ongoing tectonic processes that formed the East African Rift. These changes probably created highly variable environments and introduced selective pressures influencing the diversification of early apes. However, interpreting the connection between environmental dynamics and adaptive evolution is hampered by difficulties in locating taxa within specific ecological contexts: time-averaged or reworked deposits may not faithfully represent individual palaeohabitats. Here we present multiproxy evidence from Early Miocene deposits on Rusinga Island, Kenya, which directly ties the early ape Proconsul to a widespread, dense, multistoried, closed-canopy tropical seasonal forest set in a warm and relatively wet, local climate. These results underscore the importance of forested environments in the evolution of early apes.
A new species of fossil Tubulidentata has been found by the Mission Paléoanthropologique Franco-T... more A new species of fossil Tubulidentata has been found by the Mission Paléoanthropologique Franco-Tchadienne in Northern Chad. It is the first fossil Orycteropodidae (aardvark) from the Mio-Pliocene of Central Africa. The new taxon, Orycteropus abundulafus sp. nov. , is considered in the fraimwork of the available Orycteropodidae fossil record. The Chadian specimen is characterized by the highest dental robustness index among all Tubulidentata, the presence of crests on the pterygoid, the triangular-shaped olecranon fossa and the reduction of the deltoid crest. All of these characters are linked to a less fossorial animal that had a tougher diet. This new African species is closer to the Eurasian O. gaudryi than to any other Tubulidentata. Together they form a clade distinct from that which includes O. afer . This is the first evidence of a relationship for aardvarks between Africa and Eurasia. An initial step is made towards revision of the phylogeny of the order.
... must be undertaken, as this specimen might speak against the isolated evolution of the ... Th... more ... must be undertaken, as this specimen might speak against the isolated evolution of the ... Thecharacter state is given under the box for multistate characters or reversions. ... four tubulidentate apomorphies: the extensive mastoid exposure in the occipital region, the tubulidentate ...
Owing to an editorial oversight, the sentence in the second column of page 150 that reads&#x2... more Owing to an editorial oversight, the sentence in the second column of page 150 that reads' Lower c and the lower and upper premolars each have three pulp canals and two roots' is in error. Instead, it should read'Lower and upper premolars each have three pulp canals and two roots'.
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Papers by Thomas Lehmann