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Judith C. Masters - One of the best experts on this subject based on the ideXlab platform.
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The evolution of palate shape in the Lepilemur‐Cheirogaleidae clade (Primates: Strepsirrhini).
American Journal of Physical Anthropology, 2020Co-Authors: Curswan Andrews, Judith C. Masters, Fabien Génin, Sébastien CouetteAbstract:Objectives: Phylogenies consistently group the folivorous Lepilemur species with the small-bodied insectivorous-frugivorous cheirogaleids. Juvenile lepilemurs and adult cheirogaleids share allometries in most aspects of skull morphology, except the palate. We investigated potential influences on palate shape in these taxa and several outgroups using geometric morphometrics. Materials and methods: Our sample included representatives of four extant strepsirrhine families, Cheirogaleidae (including Lepilemurinae), Lemuridae, Indriidae, and Galagidae, and one subfossil Megaladapis. Our dataset comprised 32 landmarks collected from 397 specimens representing 15 genera and 28 species, and was analyzed using generalized procrustes analyses and between group principal component analysis. We explored the influence of size, phylogeny, diet, and the propagation of loud vocalizations on palate shape. Results: While congeneric species clustered within the morphospace, the phylomorphospace did not mirror molecular phylogenetic hypotheses of higher-order relationships. Four palate forms were distinguished within the Cheirogaleidae. Diet, strongly linked to body size, had the single greatest influence on palate shape. The production of long-distance advertisement calls was most often associated with positive scores on the PC1 axis. Discussion: Our results suggest that the extensive variation in palate shape among Cheirogaleidae is related to dietary shifts that accompanied changes in body size during the clade's radiation. Molecular phylogenies indicate that cheirogaleid diversification involved repeated dwarfing events, which in turn drove dietary shifts from ancestral folivory-frugivory to frugivory, gummivory, and faunivory in the descendant species. The elongated Lepilemur palate is probably related to accelerated eruption of the cheek teeth to render juveniles competent to shear leaves upon weaning.
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The evolution of palate shape in the Lepilemur-Cheirogaleidae clade (Primates: Strepsirrhini).
American journal of physical anthropology, 2020Co-Authors: Curswan A. Andrews, Judith C. Masters, Fabien Génin, Sébastien CouetteAbstract:Objectives: Phylogenies consistently group the folivorous Lepilemur species with the small-bodied insectivorous-frugivorous cheirogaleids. Juvenile lepilemurs and adult cheirogaleids share allometries in most aspects of skull morphology, except the palate. We investigated potential influences on palate shape in these taxa and several outgroups using geometric morphometrics. Materials and methods: Our sample included representatives of four extant strepsirrhine families, Cheirogaleidae (including Lepilemurinae), Lemuridae, Indriidae, and Galagidae, and one subfossil Megaladapis. Our dataset comprised 32 landmarks collected from 397 specimens representing 15 genera and 28 species, and was analyzed using generalized procrustes analyses and between group principal component analysis. We explored the influence of size, phylogeny, diet, and the propagation of loud vocalizations on palate shape. Results: While congeneric species clustered within the morphospace, the phylomorphospace did not mirror molecular phylogenetic hypotheses of higher-order relationships. Four palate forms were distinguished within the Cheirogaleidae. Diet, strongly linked to body size, had the single greatest influence on palate shape. The production of long-distance advertisement calls was most often associated with positive scores on the PC1 axis. Discussion: Our results suggest that the extensive variation in palate shape among Cheirogaleidae is related to dietary shifts that accompanied changes in body size during the clade's radiation. Molecular phylogenies indicate that cheirogaleid diversification involved repeated dwarfing events, which in turn drove dietary shifts from ancestral folivory-frugivory to frugivory, gummivory, and faunivory in the descendant species. The elongated Lepilemur palate is probably related to accelerated eruption of the cheek teeth to render juveniles competent to shear leaves upon weaning.
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Case 3742 – Galago demidoff Fischer, 1806 (currently Galagoides ; Mammalia, Primates, Galagidae): proposed conservation of the specific name and designation of a neotype. Lemur minutus Cuvier, 1797: proposed designation of a neotype
The Bulletin of Zoological Nomenclature, 2018Co-Authors: Paulina D. Jenkins, Judith C. Masters, Colin P. Groves, Sébastien CouetteAbstract:The purpose of this application, under Articles 11, 23, 31 and 32 of the Code, is to confirm the availability of and to maintain the usage of the name Galago demidoff Fischer, 1806 for Demidoff ’s Dwarf Galago from western and central Africa and its priority over the objective junior synonym Macropus ( Galago ) demidovii Fischer, 1808, and to suppress subsequent incorrect spellings, under Articles 19 and 33 of the Code. The original specimen of Galago demidoff Fischer, 1806 has been destroyed so a further purpose of this application is to designate a neotype, under Article 75.3 of the Code. A name of dubious identity, Lemur minutus Cuvier, 1797, has been confused with that of Galago demidoff and Galago senegalensis Geoffroy, 1796. This name has had no valid usage for well over a century and is here regarded as a nomen oblitum, under Article 23 of the Code. In order to clarify taxonomic status, it is also proposed to designate a neotype for Lemur minutus Cuvier, 1797, under Article 75.3 of the Code. It is proposed that G. demidoff should be maintained as the prior name for the taxon and that all subsequent incorrect spellings of the name be suppressed.
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A new genus for the eastern dwarf galagos (Primates: Galagidae).
Zoological Journal of the Linnean Society, 2017Co-Authors: Judith C. Masters, Massimiliano Delpero, Fabien Génin, Sébastien Couette, Colin P. Groves, Stephen D. Nash, Luca PozziAbstract:The family Galagidae (African galagos or bushbabies) comprises five genera: EuoticusGray, 1872; GalagoGeoffroy Saint-Hilaire, 1796; GalagoidesSmith, 1833; OtolemurCoquerel, 1859; and SciurocheirusGray, 1872, none of which is regarded as monotypic, but some (Euoticus and Otolemur) certainly qualify as oligotypic. We argue for the recognition of a sixth genus, if the taxonomy is to reflect galagid evolution accurately. Genetic evidence has consistently demonstrated that the taxa currently referred to the genus Galagoides are not monophyletic but form two clades (a western and an eastern clade) that do not share an exclusive common ancestor; we review 20 years of genetic studies that corroborate this conclusion. Further, we compare vocalizations emitted by small-bodied galagids with proposed phylogenetic relationships and demonstrate congruence between these data sets. Morphological evidence, however, is not entirely congruent with genetic reconstructions; parallel dwarfing in the two clades has led to convergences in skull size and shape that have complicated the classification of the smaller species. We present a craniodental morphometric analysis of small-bodied galagid genera that identifies distinguishing characters for the genera and supports our proposal that five taxa currently subsumed under Galagoides (Galagoides cocos, Galagoides granti, Galagoides orinus, Galagoides rondoensis and Galagoides zanzibaricus) be placed in their own genus, for which we propose the name Paragalago.
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A giant among dwarfs: a new species of galago (Primates: Galagidae) from Angola
American journal of physical anthropology, 2017Co-Authors: Magdalena S. Svensson, K. Anne-isola Nekaris, Andrew Perkin, Judith C. Masters, Sébastien Couette, Elena Bersacola, Michael S. L. Mills, Rachel A. Munds, Vincent Nijman, Simon K. BearderAbstract:Objectives Based on vocalization recordings of an unknown galago species, our main objectives were to compare morphology and call structure with known closely-related taxa and describe a new species of galago. Materials and methods We conducted field surveys in three forest habitats along the escarpment region in western Angola (Kumbira Forest, Bimbe Area, and Northern Scarp Forest), and examined galago specimens from museums worldwide. We digitized and analyzed calls using Avisoft SASLab Pro software. We also compared museum specimens from Angola with other Galago and Galagoides specimens, and conducted comparative analyses (ANOVA and between group principle component analysis) based on a set of twelve linear measurements of skulls and teeth. Results We describe the new species to which we give the name Angolan dwarf galago, Galagoides kumbirensis sp. nov. The new species has a loud and characteristic crescendo call, used by other Galagoides spp. (sensu stricto) in West Africa to attract companions and repel rivals. However, this call shows species-typical differences from its closest relatives. Galagoides kumbirensis sp. nov. is also distinguished by differences in the skull morphology, pelage color and facial markings, as well as a larger body size, similar to that of Galago moholi, which is not known to be sympatric. Conclusion This discovery points to the importance of Angolan forests as refuges for endemic biodiversity. These forests are under severe threat from overexploitation, and there is an urgent need to establish conservation measures and designate protected areas.
Sébastien Couette - One of the best experts on this subject based on the ideXlab platform.
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The evolution of palate shape in the Lepilemur‐Cheirogaleidae clade (Primates: Strepsirrhini).
American Journal of Physical Anthropology, 2020Co-Authors: Curswan Andrews, Judith C. Masters, Fabien Génin, Sébastien CouetteAbstract:Objectives: Phylogenies consistently group the folivorous Lepilemur species with the small-bodied insectivorous-frugivorous cheirogaleids. Juvenile lepilemurs and adult cheirogaleids share allometries in most aspects of skull morphology, except the palate. We investigated potential influences on palate shape in these taxa and several outgroups using geometric morphometrics. Materials and methods: Our sample included representatives of four extant strepsirrhine families, Cheirogaleidae (including Lepilemurinae), Lemuridae, Indriidae, and Galagidae, and one subfossil Megaladapis. Our dataset comprised 32 landmarks collected from 397 specimens representing 15 genera and 28 species, and was analyzed using generalized procrustes analyses and between group principal component analysis. We explored the influence of size, phylogeny, diet, and the propagation of loud vocalizations on palate shape. Results: While congeneric species clustered within the morphospace, the phylomorphospace did not mirror molecular phylogenetic hypotheses of higher-order relationships. Four palate forms were distinguished within the Cheirogaleidae. Diet, strongly linked to body size, had the single greatest influence on palate shape. The production of long-distance advertisement calls was most often associated with positive scores on the PC1 axis. Discussion: Our results suggest that the extensive variation in palate shape among Cheirogaleidae is related to dietary shifts that accompanied changes in body size during the clade's radiation. Molecular phylogenies indicate that cheirogaleid diversification involved repeated dwarfing events, which in turn drove dietary shifts from ancestral folivory-frugivory to frugivory, gummivory, and faunivory in the descendant species. The elongated Lepilemur palate is probably related to accelerated eruption of the cheek teeth to render juveniles competent to shear leaves upon weaning.
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The evolution of palate shape in the Lepilemur-Cheirogaleidae clade (Primates: Strepsirrhini).
American journal of physical anthropology, 2020Co-Authors: Curswan A. Andrews, Judith C. Masters, Fabien Génin, Sébastien CouetteAbstract:Objectives: Phylogenies consistently group the folivorous Lepilemur species with the small-bodied insectivorous-frugivorous cheirogaleids. Juvenile lepilemurs and adult cheirogaleids share allometries in most aspects of skull morphology, except the palate. We investigated potential influences on palate shape in these taxa and several outgroups using geometric morphometrics. Materials and methods: Our sample included representatives of four extant strepsirrhine families, Cheirogaleidae (including Lepilemurinae), Lemuridae, Indriidae, and Galagidae, and one subfossil Megaladapis. Our dataset comprised 32 landmarks collected from 397 specimens representing 15 genera and 28 species, and was analyzed using generalized procrustes analyses and between group principal component analysis. We explored the influence of size, phylogeny, diet, and the propagation of loud vocalizations on palate shape. Results: While congeneric species clustered within the morphospace, the phylomorphospace did not mirror molecular phylogenetic hypotheses of higher-order relationships. Four palate forms were distinguished within the Cheirogaleidae. Diet, strongly linked to body size, had the single greatest influence on palate shape. The production of long-distance advertisement calls was most often associated with positive scores on the PC1 axis. Discussion: Our results suggest that the extensive variation in palate shape among Cheirogaleidae is related to dietary shifts that accompanied changes in body size during the clade's radiation. Molecular phylogenies indicate that cheirogaleid diversification involved repeated dwarfing events, which in turn drove dietary shifts from ancestral folivory-frugivory to frugivory, gummivory, and faunivory in the descendant species. The elongated Lepilemur palate is probably related to accelerated eruption of the cheek teeth to render juveniles competent to shear leaves upon weaning.
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Case 3742 - Galago demidoff Fischer, 1806 (currently Galagoides ; Mammalia, Primates, Galagidae ): proposed conservation of the specific name and designation of a neotype. Lemur minutus Cuvier, 1797: proposed designation of a neotype.
The Bulletin of Zoological Nomenclature, 2018Co-Authors: Paulina Jenkins, Judith Masters, Colin Groves, Sébastien CouetteAbstract:The purpose of this application, under Articles 11, 23, 31 and 32 of the Code, is to confirm the availability of and to maintain the usage of the name Galago demidoff Fischer, 1806 for Demidoff ’s Dwarf Galago from western and central Africa and its priority over the objective junior synonym Macropus (Galago) demidovii Fischer, 1808, and to suppress subsequent incorrect spellings, under Articles 19 and 33 of the Code. The original specimen of Galago demidoff Fischer, 1806 has been destroyed so a further purpose of this application is to designate a neotype, under Article 75.3 of the Code. A name of dubious identity, Lemur minutus Cuvier, 1797, has been confused with that of Galago demidoff and Galago senegalensis Geoffroy, 1796. This name has had no valid usage for well over a century and is here regarded as a nomen oblitum, under Article 23 of the Code. In order to clarify taxonomic status, it is also proposed to designate a neotype for Lemur minutus Cuvier, 1797, under Article 75.3 of the Code. It is proposed that G. demidoff should be maintained as the prior name for the taxon and that all subsequent incorrect spellings of the name be suppressed.
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Case 3742 – Galago demidoff Fischer, 1806 (currently Galagoides ; Mammalia, Primates, Galagidae): proposed conservation of the specific name and designation of a neotype. Lemur minutus Cuvier, 1797: proposed designation of a neotype
The Bulletin of Zoological Nomenclature, 2018Co-Authors: Paulina D. Jenkins, Judith C. Masters, Colin P. Groves, Sébastien CouetteAbstract:The purpose of this application, under Articles 11, 23, 31 and 32 of the Code, is to confirm the availability of and to maintain the usage of the name Galago demidoff Fischer, 1806 for Demidoff ’s Dwarf Galago from western and central Africa and its priority over the objective junior synonym Macropus ( Galago ) demidovii Fischer, 1808, and to suppress subsequent incorrect spellings, under Articles 19 and 33 of the Code. The original specimen of Galago demidoff Fischer, 1806 has been destroyed so a further purpose of this application is to designate a neotype, under Article 75.3 of the Code. A name of dubious identity, Lemur minutus Cuvier, 1797, has been confused with that of Galago demidoff and Galago senegalensis Geoffroy, 1796. This name has had no valid usage for well over a century and is here regarded as a nomen oblitum, under Article 23 of the Code. In order to clarify taxonomic status, it is also proposed to designate a neotype for Lemur minutus Cuvier, 1797, under Article 75.3 of the Code. It is proposed that G. demidoff should be maintained as the prior name for the taxon and that all subsequent incorrect spellings of the name be suppressed.
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A new genus for the eastern dwarf galagos (Primates: Galagidae).
Zoological Journal of the Linnean Society, 2017Co-Authors: Judith C. Masters, Massimiliano Delpero, Fabien Génin, Sébastien Couette, Colin P. Groves, Stephen D. Nash, Luca PozziAbstract:The family Galagidae (African galagos or bushbabies) comprises five genera: EuoticusGray, 1872; GalagoGeoffroy Saint-Hilaire, 1796; GalagoidesSmith, 1833; OtolemurCoquerel, 1859; and SciurocheirusGray, 1872, none of which is regarded as monotypic, but some (Euoticus and Otolemur) certainly qualify as oligotypic. We argue for the recognition of a sixth genus, if the taxonomy is to reflect galagid evolution accurately. Genetic evidence has consistently demonstrated that the taxa currently referred to the genus Galagoides are not monophyletic but form two clades (a western and an eastern clade) that do not share an exclusive common ancestor; we review 20 years of genetic studies that corroborate this conclusion. Further, we compare vocalizations emitted by small-bodied galagids with proposed phylogenetic relationships and demonstrate congruence between these data sets. Morphological evidence, however, is not entirely congruent with genetic reconstructions; parallel dwarfing in the two clades has led to convergences in skull size and shape that have complicated the classification of the smaller species. We present a craniodental morphometric analysis of small-bodied galagid genera that identifies distinguishing characters for the genera and supports our proposal that five taxa currently subsumed under Galagoides (Galagoides cocos, Galagoides granti, Galagoides orinus, Galagoides rondoensis and Galagoides zanzibaricus) be placed in their own genus, for which we propose the name Paragalago.
Luca Pozzi - One of the best experts on this subject based on the ideXlab platform.
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A new genus for the eastern dwarf galagos (Primates: Galagidae).
Zoological Journal of the Linnean Society, 2017Co-Authors: Judith C. Masters, Massimiliano Delpero, Fabien Génin, Sébastien Couette, Colin P. Groves, Stephen D. Nash, Luca PozziAbstract:The family Galagidae (African galagos or bushbabies) comprises five genera: EuoticusGray, 1872; GalagoGeoffroy Saint-Hilaire, 1796; GalagoidesSmith, 1833; OtolemurCoquerel, 1859; and SciurocheirusGray, 1872, none of which is regarded as monotypic, but some (Euoticus and Otolemur) certainly qualify as oligotypic. We argue for the recognition of a sixth genus, if the taxonomy is to reflect galagid evolution accurately. Genetic evidence has consistently demonstrated that the taxa currently referred to the genus Galagoides are not monophyletic but form two clades (a western and an eastern clade) that do not share an exclusive common ancestor; we review 20 years of genetic studies that corroborate this conclusion. Further, we compare vocalizations emitted by small-bodied galagids with proposed phylogenetic relationships and demonstrate congruence between these data sets. Morphological evidence, however, is not entirely congruent with genetic reconstructions; parallel dwarfing in the two clades has led to convergences in skull size and shape that have complicated the classification of the smaller species. We present a craniodental morphometric analysis of small-bodied galagid genera that identifies distinguishing characters for the genera and supports our proposal that five taxa currently subsumed under Galagoides (Galagoides cocos, Galagoides granti, Galagoides orinus, Galagoides rondoensis and Galagoides zanzibaricus) be placed in their own genus, for which we propose the name Paragalago.
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The role of forest expansion and contraction in species diversification among galagos (Primates: Galagidae)
Journal of Biogeography, 2016Co-Authors: Luca PozziAbstract:Aim Here, I investigate galagid diversification and current distribution in the context of major climatic and geological events in sub-Saharan Africa. Given their widespread distribution and presence in a large range of diverse habitats, galagids represent an excellent group to investigate the role of forest contraction and expansion on biological diversification in sub-Saharan Africa. Location Sub-Saharan Africa (Afrotropical Region). Methods I assembled a supermatrix including 53 nuclear loci and three mitochondrial markers for 94% of the galagid species currently recognized. Bayesian and maximum likelihood methods were used to infer phylogenetic relationships and times of divergence within the family. Ancestral ranges were estimated using several methods, including ‘BioGeoBEARS’ and rasp. Results Phylogenetic analyses corroborated previous results regarding the evolutionary history of this family: (1) early origin of the family soon after the Eocene-Oligocene boundary; (2) dwarf galagos (Galagoides spp.) represent a polyphyletic group with two well-defined clades, one in central-west Africa and one in the east; and (3) divergences within galagids are relatively old with most genera already present by the Late Miocene. The biogeographical analysis indicates central African origins and subsequent expansion to the east in the Early-Middle Miocene. An expansion to the northern and southern savannas occurred between the Late Pliocene and the Middle Pleistocene. Main conclusions The results of this study clarify several questions related to the evolutionary history of the Galagidae in the context of sub-Saharan African biogeography. This study suggests that galagid evolution and diversification was affected by three major climatic episodes: (1) the global cooling and forest contraction in the Early Oligocene, (2) the forest expansion and the uplift of the African rifts in the Miocene and (3) the aridification and extension of open woodlands and savannas in the Late Miocene and Plio-Pleistocene.
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Remarkable ancient divergences amongst neglected lorisiform primates
Zoological journal of the Linnean Society, 2015Co-Authors: Luca Pozzi, Simon K. Bearder, K. Anne-isola Nekaris, Andrew Perkin, Elizabeth Pimley, Helga Schulze, Ulrike Streicher, Tilo Nadler, Andrew C. Kitchener, Hans ZischlerAbstract:Lorisiform primates (Primates: Strepsirrhini: Lorisiformes) represent almost 10% of the living primate species and are widely distributed in sub-Saharan Africa and South/South-East Asia; however, their taxonomy, evolutionary history, and biogeography are still poorly understood. In this study we report the largest molecular phylogeny in terms of the number of represented taxa. We sequenced the complete mitochondrial cytochrome b gene for 86 lorisiform specimens, including ∼80% of all the species currently recognized. Our results support the monophyly of the Galagidae, but a common ancestry of the Lorisinae and Perodicticinae (family Lorisidae) was not recovered. These three lineages have early origins, with the Galagidae and the Lorisinae diverging in the Oligocene at about 30 Mya and the Perodicticinae emerging in the early Miocene. Our mitochondrial phylogeny agrees with recent studies based on nuclear data, and supports Euoticus as the oldest galagid lineage and the polyphyletic status of Galagoides. Moreover, we have elucidated phylogenetic relationships for several species never included before in a molecular phylogeny. The results obtained in this study suggest that lorisiform diversity remains substantially underestimated and that previously unnoticed cryptic diversity might be present within many lineages, thus urgently requiring a comprehensive taxonomic revision of this primate group.
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A multilocus phylogeny reveals deep lineages within African galagids (Primates: Galagidae)
BMC evolutionary biology, 2014Co-Authors: Luca Pozzi, Todd R. Disotell, Judith C. MastersAbstract:Background: Bushbabies (Galagidae) are among the most morphologically cryptic of all primates and their diversity and relationships are some of the most longstanding problems in primatology. Our knowledge of galagid evolutionary history has been limited by a lack of appropriate molecular data and a paucity of fossils. Most phylogenetic studies have produced conflicting results for many clades, and even the relationships among genera remain uncertain. To clarify galagid evolutionary history, we assembled the largest molecular dataset for galagos to date by sequencing 27 independent loci. We inferred phylogenetic relationships using concatenated maximum-likelihood and Bayesian analyses, and also coalescent-based species tree methods to account for gene tree heterogeneity due to incomplete lineage sorting. Results: The genus Euoticus was identified as sister taxon to the rest of the galagids and the genus Galagoides was not recovered as monophyletic, suggesting that a new generic name for the Zanzibar complex is required. Despite the amount of genetic data collected in this study, the monophyly of the family Lorisidae remained poorly supported, probably due to the short internode between the Lorisidae/Galagidae split and the origin of the African and Asian lorisid clades. One major result was the relatively old origin for the most recent common ancestor of all living galagids soon after the Eocene-Oligocene boundary. Conclusions: Using a multilocus approach, our results suggest an early origin for the crown Galagidae, soon after the Eocene-Oligocene boundary, making Euoticus one of the oldest lineages within extant Primates. This result also implies that one – or possibly more – stem radiations diverged in the Late Eocene and persisted for several million years alongside members of the crown group.
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A multilocus phylogeny reveals deep lineages within African galagids (Primates: Galagidae)
BMC evolutionary biology, 2014Co-Authors: Luca Pozzi, Todd R. Disotell, Judith C. MastersAbstract:Bushbabies (Galagidae) are among the most morphologically cryptic of all primates and their diversity and relationships are some of the most longstanding problems in primatology. Our knowledge of galagid evolutionary history has been limited by a lack of appropriate molecular data and a paucity of fossils. Most phylogenetic studies have produced conflicting results for many clades, and even the relationships among genera remain uncertain. To clarify galagid evolutionary history, we assembled the largest molecular dataset for galagos to date by sequencing 27 independent loci. We inferred phylogenetic relationships using concatenated maximum-likelihood and Bayesian analyses, and also coalescent-based species tree methods to account for gene tree heterogeneity due to incomplete lineage sorting. The genus Euoticus was identified as sister taxon to the rest of the galagids and the genus Galagoides was not recovered as monophyletic, suggesting that a new generic name for the Zanzibar complex is required. Despite the amount of genetic data collected in this study, the monophyly of the family Lorisidae remained poorly supported, probably due to the short internode between the Lorisidae/Galagidae split and the origin of the African and Asian lorisid clades. One major result was the relatively old origin for the most recent common ancestor of all living galagids soon after the Eocene-Oligocene boundary. Using a multilocus approach, our results suggest an early origin for the crown Galagidae, soon after the Eocene-Oligocene boundary, making Euoticus one of the oldest lineages within extant Primates. This result also implies that one – or possibly more – stem radiations diverged in the Late Eocene and persisted for several million years alongside members of the crown group.
Simon K. Bearder - One of the best experts on this subject based on the ideXlab platform.
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Low Geographic and Subspecific Variation in the Loud Call of the Widespread and Phenotypically Cryptic Northern Lesser Galago (Galago senegalensis) Suggests Taxonomic Uniformity.
Folia primatologica; international journal of primatology, 2019Co-Authors: Magdalena S. Svensson, Simon K. Bearder, Thomas M. Butynski, Yvonne A. De Jong, Irena Schneiderová, Vincent NijmanAbstract:Like other nocturnal primates, many species of galago (Galagidae) are phenotypically cryptic, making their taxonomic status difficult to resolve. Recent taxonomic work has disentangled some of the confusion. This has resulted in an increase in the number of recognised galago species. The most widespread galago species, and indeed the most widespread nocturnal primate, is the northern lesser galago (Galago senegalensis) whose geographic range stretches >7,000 km across Africa. Based on morphology, 4 subspecies are currently recognised: G. s. senegalensis, G. s. braccatus, G. s. sotikae and G. s. dunni. We explore geographic and subspecific acoustic variation in G. senegalensis, testing three hypotheses: isolation by distance, genetic basis, and isolation by barrier. There is statistical support for isolation by distance for 2 of 4 call parameters (fundamental frequency and unit length). Geographic distance explains a moderate amount of the acoustic variation. Discriminant function analysis provides some degree of separation of geographic regions and subspecies, but the percentage of misdesignation is high. Despite having (putative) parapatric geographic ranges, the most pronounced acoustic differences are between G. s. senegalensis and G. s. dunni. The findings suggest that the Eastern Rift Valley and Niger River are significant barriers for G. senegalensis. The acoustic structures of the loud calls of 121 individuals from 28 widespread sites are not significantly different. Although this makes it unlikely that additional unrecognised species occur within G. senegalensis at the sites sampled, vast areas of the geographic range remain unsampled. We show that wide-ranging species do not necessarily exhibit large amounts of variation in their vocal repertoire. This pattern may also be present in nocturnal primates with smaller geographic ranges.
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A giant among dwarfs: a new species of galago (Primates: Galagidae) from Angola
American journal of physical anthropology, 2017Co-Authors: Magdalena S. Svensson, K. Anne-isola Nekaris, Andrew Perkin, Judith C. Masters, Sébastien Couette, Elena Bersacola, Michael S. L. Mills, Rachel A. Munds, Vincent Nijman, Simon K. BearderAbstract:Objectives Based on vocalization recordings of an unknown galago species, our main objectives were to compare morphology and call structure with known closely-related taxa and describe a new species of galago. Materials and methods We conducted field surveys in three forest habitats along the escarpment region in western Angola (Kumbira Forest, Bimbe Area, and Northern Scarp Forest), and examined galago specimens from museums worldwide. We digitized and analyzed calls using Avisoft SASLab Pro software. We also compared museum specimens from Angola with other Galago and Galagoides specimens, and conducted comparative analyses (ANOVA and between group principle component analysis) based on a set of twelve linear measurements of skulls and teeth. Results We describe the new species to which we give the name Angolan dwarf galago, Galagoides kumbirensis sp. nov. The new species has a loud and characteristic crescendo call, used by other Galagoides spp. (sensu stricto) in West Africa to attract companions and repel rivals. However, this call shows species-typical differences from its closest relatives. Galagoides kumbirensis sp. nov. is also distinguished by differences in the skull morphology, pelage color and facial markings, as well as a larger body size, similar to that of Galago moholi, which is not known to be sympatric. Conclusion This discovery points to the importance of Angolan forests as refuges for endemic biodiversity. These forests are under severe threat from overexploitation, and there is an urgent need to establish conservation measures and designate protected areas.
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Remarkable ancient divergences amongst neglected lorisiform primates
Zoological journal of the Linnean Society, 2015Co-Authors: Luca Pozzi, Simon K. Bearder, K. Anne-isola Nekaris, Andrew Perkin, Elizabeth Pimley, Helga Schulze, Ulrike Streicher, Tilo Nadler, Andrew C. Kitchener, Hans ZischlerAbstract:Lorisiform primates (Primates: Strepsirrhini: Lorisiformes) represent almost 10% of the living primate species and are widely distributed in sub-Saharan Africa and South/South-East Asia; however, their taxonomy, evolutionary history, and biogeography are still poorly understood. In this study we report the largest molecular phylogeny in terms of the number of represented taxa. We sequenced the complete mitochondrial cytochrome b gene for 86 lorisiform specimens, including ∼80% of all the species currently recognized. Our results support the monophyly of the Galagidae, but a common ancestry of the Lorisinae and Perodicticinae (family Lorisidae) was not recovered. These three lineages have early origins, with the Galagidae and the Lorisinae diverging in the Oligocene at about 30 Mya and the Perodicticinae emerging in the early Miocene. Our mitochondrial phylogeny agrees with recent studies based on nuclear data, and supports Euoticus as the oldest galagid lineage and the polyphyletic status of Galagoides. Moreover, we have elucidated phylogenetic relationships for several species never included before in a molecular phylogeny. The results obtained in this study suggest that lorisiform diversity remains substantially underestimated and that previously unnoticed cryptic diversity might be present within many lineages, thus urgently requiring a comprehensive taxonomic revision of this primate group.
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Vocal Profiles for the Galagos: A Tool for Identification
Primate Conservation, 2013Co-Authors: Simon K. Bearder, Thomas M. Butynski, Yvonne A. De JongAbstract:The galagos (Family Galagidae) of Africa are nocturnal, small, and often difficult to observe, and most species are phenotypically cryptic. As such, galagos are frequently difficult to identify with confidence, particularly in the field. Being nocturnal, conspecifics mainly identify each other using auditory and olfactory cues, not visual signals. All galagos produce species-specific ‘loud calls’ (or ‘advertisement calls’). Loud calls have several functions, one of which is long-distance species identification. Knowing this, field scientists are now able to identify all currently recognized species of galagos by their loud calls.
Hans Zischler - One of the best experts on this subject based on the ideXlab platform.
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Remarkable ancient divergences amongst neglected lorisiform primates
Zoological journal of the Linnean Society, 2015Co-Authors: Luca Pozzi, Simon K. Bearder, K. Anne-isola Nekaris, Andrew Perkin, Elizabeth Pimley, Helga Schulze, Ulrike Streicher, Tilo Nadler, Andrew C. Kitchener, Hans ZischlerAbstract:Lorisiform primates (Primates: Strepsirrhini: Lorisiformes) represent almost 10% of the living primate species and are widely distributed in sub-Saharan Africa and South/South-East Asia; however, their taxonomy, evolutionary history, and biogeography are still poorly understood. In this study we report the largest molecular phylogeny in terms of the number of represented taxa. We sequenced the complete mitochondrial cytochrome b gene for 86 lorisiform specimens, including ∼80% of all the species currently recognized. Our results support the monophyly of the Galagidae, but a common ancestry of the Lorisinae and Perodicticinae (family Lorisidae) was not recovered. These three lineages have early origins, with the Galagidae and the Lorisinae diverging in the Oligocene at about 30 Mya and the Perodicticinae emerging in the early Miocene. Our mitochondrial phylogeny agrees with recent studies based on nuclear data, and supports Euoticus as the oldest galagid lineage and the polyphyletic status of Galagoides. Moreover, we have elucidated phylogenetic relationships for several species never included before in a molecular phylogeny. The results obtained in this study suggest that lorisiform diversity remains substantially underestimated and that previously unnoticed cryptic diversity might be present within many lineages, thus urgently requiring a comprehensive taxonomic revision of this primate group.
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Primate jumping genes elucidate strepsirrhine phylogeny.
Proceedings of the National Academy of Sciences of the United States of America, 2004Co-Authors: Christian Roos, Jürgen Schmitz, Hans ZischlerAbstract:Transposable elements provide a highly informative marker system for analyzing evolutionary histories. To solve controversially discussed topics in strepsirrhine phylogeny, we characterized 61 loci containing short interspersed elements (SINEs) and determined the SINE presence–absence pattern at orthologous loci in a representative strepsirrhine panel. This SINE monolocus study was complemented by a Southern blot analysis tracing multiple loci of two different strepsirrhine specific SINEs. The results thereof were combined with phylogenetic trees reconstructed on the basis of complete mitochondrial cytochrome b sequences from all recognized strepsirrhine genera. Here we present evidence for (i) a sister group relationship of Malagasy Chiromyiformes and Lemuriformes, (ii) Lorisidae being a monophyletic sister clade to the Galagidae, and (iii) common ancestry of African and Asian lorisids. Based on these findings, we conclude that strepsirrhines originated in Africa and that Madagascar and Asia were colonized by respective single immigration events. In agreement with paleocontinental data, the molecular analyses suggest a crossing of the Mozambique channel by rafting between the late Cretaceous and the middle Eocene, whereas Asia was most likely colonized between the early Eocene and the middle Oligocene on a continental route. Furthermore, one SINE integration links the two Lemuriformes families, Lemuridae and Indriidae, indicating a common origin of diurnality or cathemerality and a later reversal to nocturnality by the indriid genus Avahi.
