Sebastien Couette
Ecole Pratique des Hautes Etudes, SVT, Faculty Member
- Université de Bourgogne, Biogeosciences, Faculty Memberadd
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8 pagesNational audienc
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Sagittal otolith shape analysis is one of the most widespread techniques worldwide to discriminate fish stock units, as this proxy integrates both environmental and genetic factors. All previous otolith shape studies have been carried out... more
Sagittal otolith shape analysis is one of the most widespread techniques worldwide to discriminate fish stock units, as this proxy integrates both environmental and genetic factors. All previous otolith shape studies have been carried out using two-dimensional (2D) images, a partial representation of the whole shape of the otolith. However, prior to the identification of stock unit boundaries, the influence of other potential drivers controlling the otolith shape must be analysed to limit their bias. In this study, the presence of asymmetry in otolith shape depending on the inner ear side (i.e., left versus right inner ears) was tested by comparing the approaches of 2D and three-dimensional (3D) sagittal otolith shape analyses. Eighty-two red mullet adults (Mullus barbatus) from three locations in the eastern part of the Mediterranean Sea were studied. Fourier harmonic descriptors computed from 2D outlines and spherical harmonic descriptors computed from 3D meshes were used to evalu...
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International audienceThe vestibular system of the inner ear, highly involved in maintaining balance during activities and positional behaviour of animals, has been deeply studied in order to link its morphology with the specific type of... more
International audienceThe vestibular system of the inner ear, highly involved in maintaining balance during activities and positional behaviour of animals, has been deeply studied in order to link its morphology with the specific type of locomotion. Previous studies (e.g. Perier et al. 2016, Gonzales et al. 2018) have shown that, in primates, the amount of morphological variation is higher in slow-moving species than in fast-moving ones. These results indicate a lower selective pressure and a reduced functional demand for postural adjustments in the former group, and a higher selective pressure for balance and postural capabilities in the latter. In this study, we assessed if the difference in selective pressure are also linked to the fuctuating asymmetry levels of the vestibular system, and to which extent. Fluctuating asymmetry is defined as a non-directional variation between left and right sides of a bilateral character, and it may rise as a result of an inability to control development under genetic or environmental stress. There are very few analyses of the interspecific variation of the asymmetry levels of this organ in mammals in general (Berlin et al. 2013), and to our knowledge none so far at the intraspecific level. Here we analyzed the intraspecific variation of the bony labyrinth (inner ear) morphology and of the fuctuating asymmetry levels of left and right labyrinths among six species of lorisiform primates differing in their activities and positional behaviours of their locomotor repertoires: three being slow-moving (Loris tardigradus, Nycticebus coucang, and Perodicticus potto), and three being fast-moving taxa (Paragalago granti, Galago moholi, and Otolemur crassicaudatus). Our results highlight the difference in amount of intraspecific variation between slow-moving and fast-moving taxa. Furthermore, fuctuating asymmetry levels of slow-moving taxa also tend to be higher than in fast-moving taxa. Based on these results, it may be expected that relaxation of the selective pressure applied to the morphology of the bony labyrinth is the likely reason for this higher amount of intraspecific variation and asymmetry levels in slow-moving taxa, and that it may be related to a decreased demand for rapid postural changes
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Les habitats marins côtiers des îles subantarctiques françaises concentrent une biodiversité originale qui est aujourd'hui confrontée à des changements environnementaux dont les effets sont encore mal cernés. Comprendre l'impact... more
Les habitats marins côtiers des îles subantarctiques françaises concentrent une biodiversité originale qui est aujourd'hui confrontée à des changements environnementaux dont les effets sont encore mal cernés. Comprendre l'impact de ces changements et la réponse des écosystèmes implique de mieux les connaître mais aussi d'établir un suivi régulier et à long terme sur le terrain. Le programme Proteker, n°1044 de l'Institut polaire français Paul-Émile Victor, a été développé en partenariat avec la réserve naturelle nationale des Terres australes françaises dans le but d'établir un observatoire de la biodiversité marine côtière aux Îles Kerguelen et d'y évaluer l'effet des changements environnementaux. Les études sont réalisées à différentes échelles, des espèces aux communautés et aux habitats sous-marins par des approches pluridisciplinaires qui comprennent mesures hydrographiques, cartographie d'habitats<br> et inventaires d'espèces, analyses...
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International audienceNous présentons ici une nouvelle phosphatière fossilifère nommée Dams, située sur la commune de Caylus (Quercy, Tarn et Garonne). Son réseau karstique se développe dans les calcaires micritiques de la formation de... more
International audienceNous présentons ici une nouvelle phosphatière fossilifère nommée Dams, située sur la commune de Caylus (Quercy, Tarn et Garonne). Son réseau karstique se développe dans les calcaires micritiques de la formation de Rocamadour et s’ouvre au coeur d’une zone où le lapiaz de surface a été soigneusement curé de ses remplissages lors de l’exploitation des phosphates à la fin du 19ème siècle. L’ensemble du réseau donne accès à huit galeries pour un développement total de 250 m et préserve plusieurs plaquages et remplissages argileux au sein desquels de nombreux restes fossiles ont été découverts lors des campagnes de prospection de 2016 et 2017. Les remplissages présentent la juxtaposition de trois ensembles sédimentaires bien individualisés et d’âge clairement différents : (i) un remplissage éocène, issu du remaniement du sol formé sous climat chaud et humide de type tropical ou équatorial ; (ii) un remplissage oligocène, également issu d’un sol formé sous climat chaud et humide, et (iii) un remplissage argilo-sableux plus récent surmonté par un fin niveau d’argiles blanches de décalcification et/ou de néoformation. Les deux premiers ensembles sédimentaires ont livré trois locus fossilifères : DAM1 et DAM2 datés du niveau-repère MP19 (fin Eocène), et DAM3 daté du MP22 (début Oligocène). Ces derniers encadrent la limite Eocène-Oligocène et documentent le renouvellement faunique majeur qui l’accompagne : la Grande Coupure de Stehlin. Les deux remplissages fossilifères fini-Eocène sont exceptionnellement riches en fossiles, consistant presque exclusivement en des restes de ~200 individus d’un petit artiodactyle caïnothériidé pour lesquels la quasi-totalité des éléments squelettiques a été conservée ; DAM3, daté du début de l’Oligocène, présente une plus grande diversité de taxons, mais en moindre abondance
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ObjectivesPhylogenies 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,... more
ObjectivesPhylogenies 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 MethodsOur 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.ResultsWhile congeneric species clustered within the morphospace, the phylomorphospace did not mirror...
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The DACORD functional system orients and draws archaeological pottery, based on 3D model geometry, using modern mathematical, graphical, optimization methods. The orientation workflow combines existing approaches (normal vectors,... more
The DACORD functional system orients and draws archaeological pottery, based on 3D model geometry, using modern mathematical, graphical, optimization methods. The orientation workflow combines existing approaches (normal vectors, horizontal/vertical sections, etc.) with new methods, to segment fragments (external and internal surfaces), and to erase parts that provide no information about the rotational axis (fractures, plastic decoration, etc.). Archaeological illustrations adapted to most norms and standards of pottery drawings can then be produced from these correctly oriented models. All pottery orientation and drawing methods are implemented in DACORD software, developed in R. The DACORD system thus represents a new optimized solution for archaeology.
Research Interests: Archaeology, Prehistoric Archaeology, Art, Cultural Heritage, Digital Archaeology, and 11 moreCultural Heritage Conservation, Medieval ceramics (Archaeology), Roman Pottery, Digital reconstruction (Archaeology), Pottery, Ceramics, Roman ceramics, Neolithic pottery, Bronze Age Pottery, Ceramic Analysis Archaeology, and Pottery Archaeology
The European Eocene adapiforms include two subfamilies, the Cercamoniinae, present in the early and middle Eocene, and the Adapinae, present in the late Eocene (Franzen, 1994; Godinot, 1998; Fleagle, 1999; Gebo, 2002). The large adapine... more
The European Eocene adapiforms include two subfamilies, the Cercamoniinae, present in the early and middle Eocene, and the Adapinae, present in the late Eocene (Franzen, 1994; Godinot, 1998; Fleagle, 1999; Gebo, 2002). The large adapine species has a robust upper canine and other characters. It was named Adapis magnus by Filhol (1874), and was later placed in the genus Leptadapis by Gervais (1876). However, Gervais’ choice was seldom followed by subsequent authors. Stehlin (1912) and Depéret (1917), for example, retained Leptadapis as a subgenus of Adapis. For Stehlin, a fossil species was equivalent to a living genus; he used the name Adapis magnus in his text and figures, and Leptadapis magnus in his final stratigraphic chart of the genus Adapis (p. 1280). A single genus, Adapis, is used by Genet-Varcin (1963), Simons (1972), and Gingerich (1977, 1981). Most recent authors (Godinot, 1998; Fleagle, 1999; Gebo, 2002) kept the genus Leptadapis, following Szalay and Delson (1979). Rec...
The vestibular system of the mammalian inner ear senses angular and linear velocity of the head and enables animals to maintain their balance. Vestibular anatomy has been studied extensively in order to link its structure to particular... more
The vestibular system of the mammalian inner ear senses angular and linear velocity of the head and enables animals to maintain their balance. Vestibular anatomy has been studied extensively in order to link its structure to particular kinds of locomotion. Available evidence indicates that, in primates, slow-moving species show higher levels of vestibular variation than fast-moving taxa. We analysed intraspecific morphological variation and fluctuating asymmetry (FA) levels in the semicircular canal systems of six species of lorisiform primates: three slow-moving lorisids and three fast-moving galagids. Our results showed clear differences in levels of intraspecific variation between slow-moving and fast-moving taxa. Higher levels of variation were responsible for deviations from coplanarity for synergistic pairs of canals in slower taxa. Lorisids also presented higher levels of FA than galagids. FA is a better indicator of agility than intraspecific variation. These results suggest...
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OBJECTIVES We test the effects of body mass and phylogeny on middle ear cavity pneumatization, and the role of pneumatization in hearing function, spanning the anatomical, ecological, and behavioral diversity of nonhuman primates.... more
OBJECTIVES We test the effects of body mass and phylogeny on middle ear cavity pneumatization, and the role of pneumatization in hearing function, spanning the anatomical, ecological, and behavioral diversity of nonhuman primates. MATERIALS AND METHODS All cavities were segmented in middle ear scans of 96 specimens, from 12 strepsirrhine and 15 haplorhine extant species. We measured the tympanic cavity (TC) separately, and all other middle ear spaces together (MES), calculating the degree of pneumatization with the surface area-to-volume ratio. We tested body mass effect with linear regression; we evaluated the phylogenetic signal and selection patterns, using a Kappa statistic test, and Ornstein-Uhlenbeck models (OU). We investigated the link between pneumatization and hearing sensitivity using phylogenetic regression. RESULTS Testing body mass reveals an allometric pattern for both TC and MES dimensions. Degree of pneumatization in MES is dependent on body mass in haplorhines: larger animals have more pneumatized MES. Differences at various taxonomic ranks were observed for MES, while no phylogenetic influence was observed for TC. Infraorder selection patterns are different. Auditory performance is significantly related to degree of pneumatization, indicating that a pneumatized middle ear is associated with better perception of low frequencies. DISCUSSION Pneumatization in MES is under differential selective pressure, indicating several optima for this trait. Pneumatization in MES probably modifies hearing sensitivity through pressure regulation mechanisms, auditory bulla size reduction, and frequency modulation. This could explain strepsirrhine adaptation to high-frequency perception, while haplorhine auditory perception is adapted to a broader sound range, including high and low frequencies.
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Archaeologists spend considerable time orienting and drawing ceramic fragments by hand for documentation, to infer their manufacture, the nature of the discovery site and its chronology, and to develop hypotheses about commercial and... more
Archaeologists spend considerable time orienting and drawing ceramic fragments by hand for documentation, to infer their manufacture, the nature of the discovery site and its chronology, and to develop hypotheses about commercial and cultural exchanges, social organisation, resource exploitation, and taphonomic processes. This study presents a survey of existing solutions to the time-consuming problem of orienting and drawing pottery fragments. Orientation is based on the 3D geometry of pottery models, which can now be acquired in minutes with low-cost 3D scanners. Several methods are presented: they are based on normal vectors, or circle fittings, or profile fittings. All these methods seek to determine the optimal position of the rotation axis. We also present and discuss new approaches and improvements to existing methods. We have developed a suite of functions for the computer-assisted orientation and drawing of archaeological pottery. The profile and contours of the fragment, a...
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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. We conducted field surveys in three... more
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. 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. 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. Howev...
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... Marc Godinot*, Sébastien Couette Ecole Pratique des Hautes Etudes UMR 5143 Paléobiodiversité et Paléoenvironnements Case Courrier 38, Département d'Histoire de la ... Here we will concentrate on the skulls of large size present... more
... Marc Godinot*, Sébastien Couette Ecole Pratique des Hautes Etudes UMR 5143 Paléobiodiversité et Paléoenvironnements Case Courrier 38, Département d'Histoire de la ... Here we will concentrate on the skulls of large size present in the old Quercy collections, and only briefly ...
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We carried out a multidisciplinary study linking behavioral and morphological data from a little-known guenon species, Cercopithecus solatus, endemic to Gabon. Over a period of 9 months, we documented the pattern of stratum use associated... more
We carried out a multidisciplinary study linking behavioral and morphological data from a little-known guenon species, Cercopithecus solatus, endemic to Gabon. Over a period of 9 months, we documented the pattern of stratum use associated with postural and locomotor behavior by direct observation (650 hrs) of a semi-free-ranging breeding colony. We also conducted a morphometric analysis of the humerus and limb proportions of 90 adult specimens from 16 guenon species, including C. solatus. Field observations indicated that C. solatus monkeys spent a third of their time on the ground, similar to semi-terrestrial guenon species. We detected two patterns of stratum use: at ground level, and in trees, at a height of 3-10 m. The monkeys spent more time on the ground during the dry season than the wet season, feeding mainly at ground level, while resting, and social behaviors occurred more frequently in the tree strata. Our study of humerus size and shape, together with the analysis of limb proportions, indicated morphofunctional adaptation of C. solatus to greater terrestriality than previously thought. We therefore characterize C. solatus as a semi-terrestrial guenon, and propose a new hypothesis for the ancestral condition. By combining behavioral and morphological results, we provide new information about the adaptive strategies of the species, and the evolutionary history of guenons, thus contributing to the conservation of the sun-tailed monkey in the wild. Am. J. Primatol.
Recognition of a particularly derived eco-behavioral strategy for the genus Alouatta has been crucial for studying and understanding its equally derived cranial and postcranial morphology. The unique architecture of the skull and mandible... more
Recognition of a particularly derived eco-behavioral strategy for the
genus Alouatta has been crucial for studying and understanding its equally derived
cranial and postcranial morphology. The unique architecture of the skull and mandible
has very likely evolved in relation to both masticatory correlates associated
with an increasingly folivorous diet as well as the use of vocal communication associated
with social behavior and an energy-minimizing strategy. Comparisons of cranial
morphology using three-dimensional geometric morphometrics have
highlighted signifi cant interspecifi c shape differences. Alouatta seniculus is the
most divergent in both cranial and hyoid morphology and exhibits the most pronounced
levels of sexual dimorphism in those areas. Cranial variability is expressed
in facial prognathism and airorhynchy, basicranial fl exure, and zygomatic height.
Inter- and intraspecifi c differences based on these axes of variation are very likely
linked to interspecifi c variations in diet, behavior, and life history. This is further
evident in the dental anatomy of the genus, indicating adaptations to a shift to a
more folivorous diet. In addition, recent studies provide further evidence for signifi -
cant inter- and intraspecifi c variations in hyoid size and shape. Alouatta seniculus
possesses the largest and most infl ated hyoid bulla, and the species that occupy distributional
extremes ( A. palliata , A. caraya ) are differentiated by highly distinct hyoid
shapes. These data indicate a complex relationship between morphology and behavior,
with possible biogeographic implications. In terms of postcranial morphology,the forelimb bears a mixture of features that favor quadrupedalism with restricted
abduction and overhead extension, providing stable contact and support along
branches. In contrast, the hind limb appears to allow for a wider range of movement
in all joints, with an emphasis on thigh extension and abduction, leg rotation, and
powerful grasping with a habitually inverted foot. Interspecifi c variation reveals
traits that can be ultimately related to subtle differences in the frequency of use of
different positional modes, associated with variable eco-social factors. These
results, deriving from different anatomical regions, provide evidence for understanding
morphological variation across howler species in terms of morphofunctional
adaptations, environmental pressure, and niche partitioning.
genus Alouatta has been crucial for studying and understanding its equally derived
cranial and postcranial morphology. The unique architecture of the skull and mandible
has very likely evolved in relation to both masticatory correlates associated
with an increasingly folivorous diet as well as the use of vocal communication associated
with social behavior and an energy-minimizing strategy. Comparisons of cranial
morphology using three-dimensional geometric morphometrics have
highlighted signifi cant interspecifi c shape differences. Alouatta seniculus is the
most divergent in both cranial and hyoid morphology and exhibits the most pronounced
levels of sexual dimorphism in those areas. Cranial variability is expressed
in facial prognathism and airorhynchy, basicranial fl exure, and zygomatic height.
Inter- and intraspecifi c differences based on these axes of variation are very likely
linked to interspecifi c variations in diet, behavior, and life history. This is further
evident in the dental anatomy of the genus, indicating adaptations to a shift to a
more folivorous diet. In addition, recent studies provide further evidence for signifi -
cant inter- and intraspecifi c variations in hyoid size and shape. Alouatta seniculus
possesses the largest and most infl ated hyoid bulla, and the species that occupy distributional
extremes ( A. palliata , A. caraya ) are differentiated by highly distinct hyoid
shapes. These data indicate a complex relationship between morphology and behavior,
with possible biogeographic implications. In terms of postcranial morphology,the forelimb bears a mixture of features that favor quadrupedalism with restricted
abduction and overhead extension, providing stable contact and support along
branches. In contrast, the hind limb appears to allow for a wider range of movement
in all joints, with an emphasis on thigh extension and abduction, leg rotation, and
powerful grasping with a habitually inverted foot. Interspecifi c variation reveals
traits that can be ultimately related to subtle differences in the frequency of use of
different positional modes, associated with variable eco-social factors. These
results, deriving from different anatomical regions, provide evidence for understanding
morphological variation across howler species in terms of morphofunctional
adaptations, environmental pressure, and niche partitioning.
Archaeologists spend considerable time orienting and drawing ceramic fragments by hand for documentation, to infer their manufacture, the nature of the discovery site and its chronology, and to develop hypotheses about commercial and... more
Archaeologists spend considerable time orienting and drawing ceramic fragments by hand for documentation, to infer their
manufacture, the nature of the discovery site and its chronology, and to develop hypotheses about commercial and cultural
exchanges, social organisation, resource exploitation, and taphonomic processes. This study presents a survey of existing solutions
to the time-consuming problem of orienting and drawing pottery fragments. Orientation is based on the 3D geometry
of pottery models, which can now be acquired in minutes with low-cost 3D scanners. Several methods are presented: they
are based on normal vectors, or circle fittings, or profile fittings. All these methods seek to determine the optimal position of
the rotation axis.We also present and discuss new approaches and improvements to existing methods.We have developed a
suite of functions for the computer-assisted orientation and drawing of archaeological pottery. The profile and contours of
the fragment, as well as any possible decoration, can be depicted in various ways: photorealistic rendering or dotted patterns,
calculated by ambient occlusion, combined or not with artificial light. The general workflow, evaluated using both synthetic
and real-world fragments, is rapid, accurate, and reproducible. It drastically reduces the amount of routine work required
to document ceramic artefacts. The information produced, together with the 3D representation of the fragments, can easily
be archived and/or exchanged within the archaeological community for further research. The source code (built in the R
environment), together with an installation notice and examples, is freely downloadable.
manufacture, the nature of the discovery site and its chronology, and to develop hypotheses about commercial and cultural
exchanges, social organisation, resource exploitation, and taphonomic processes. This study presents a survey of existing solutions
to the time-consuming problem of orienting and drawing pottery fragments. Orientation is based on the 3D geometry
of pottery models, which can now be acquired in minutes with low-cost 3D scanners. Several methods are presented: they
are based on normal vectors, or circle fittings, or profile fittings. All these methods seek to determine the optimal position of
the rotation axis.We also present and discuss new approaches and improvements to existing methods.We have developed a
suite of functions for the computer-assisted orientation and drawing of archaeological pottery. The profile and contours of
the fragment, as well as any possible decoration, can be depicted in various ways: photorealistic rendering or dotted patterns,
calculated by ambient occlusion, combined or not with artificial light. The general workflow, evaluated using both synthetic
and real-world fragments, is rapid, accurate, and reproducible. It drastically reduces the amount of routine work required
to document ceramic artefacts. The information produced, together with the 3D representation of the fragments, can easily
be archived and/or exchanged within the archaeological community for further research. The source code (built in the R
environment), together with an installation notice and examples, is freely downloadable.
The genus Mesopithecus is well represented in the late Miocene of Greece by several recognized species. The present paper investigates functional aspects of the humeri of Mesopithecus delsoni/pentelicus, M. pentelicus and M. aff.... more
The genus Mesopithecus is well represented in the late Miocene of Greece by several recognized species.
The present paper investigates functional aspects of the humeri of Mesopithecus delsoni/pentelicus,
M. pentelicus and M. aff. pentelicus of several Turolian sites from central and northern Greece, using
multivariate approaches. For these purposes, we selected significant humeral functional features, which
were represented by 23 linear dimensions and three angles on 14 fossil humeri and 104 humeri from 10
genera and 22 species of extant African and Asian Colobines. All size-adjusted measurements were
examined through a principal components analysis, followed by a discriminant function analysis, and
a canonical variates analysis. All analyses revealed that the selected characters were able to discriminate
between extant colobine genera. Functional groups, such as arboreal walking/climbing, arboreal walking/
suspensory and semi-terrestrial walking, were set apart from a central cluster formed by the arboreal
walking and arboreal walking/terrestrial groups. This cluster also grouped the three studied Mesopithecus
species, which were mainly classified as arboreal walkers with significant terrestrial activities. These
observations match with paleoenvironmental reconstructions and the suggested opportunistic feeding
habits. Moreover, the overall arboreal/terrestrial locomotor tendencies of these fossil forms are discussed
in relation to their earlier migration from Africa and later dispersal to eastern and southern Asia.
The present paper investigates functional aspects of the humeri of Mesopithecus delsoni/pentelicus,
M. pentelicus and M. aff. pentelicus of several Turolian sites from central and northern Greece, using
multivariate approaches. For these purposes, we selected significant humeral functional features, which
were represented by 23 linear dimensions and three angles on 14 fossil humeri and 104 humeri from 10
genera and 22 species of extant African and Asian Colobines. All size-adjusted measurements were
examined through a principal components analysis, followed by a discriminant function analysis, and
a canonical variates analysis. All analyses revealed that the selected characters were able to discriminate
between extant colobine genera. Functional groups, such as arboreal walking/climbing, arboreal walking/
suspensory and semi-terrestrial walking, were set apart from a central cluster formed by the arboreal
walking and arboreal walking/terrestrial groups. This cluster also grouped the three studied Mesopithecus
species, which were mainly classified as arboreal walkers with significant terrestrial activities. These
observations match with paleoenvironmental reconstructions and the suggested opportunistic feeding
habits. Moreover, the overall arboreal/terrestrial locomotor tendencies of these fossil forms are discussed
in relation to their earlier migration from Africa and later dispersal to eastern and southern Asia.
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... more
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.
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.
Rock artstudiesarefacingmajortechnicalchallengesforextensivedocumentation.Nowadays,record- ing isessentiallyobtainedfromtime-consumingtracingandrubbing,techniquesthatalsorequireahigh level... more
Rock artstudiesarefacingmajortechnicalchallengesforextensivedocumentation.Nowadays,record-
ing isessentiallyobtainedfromtime-consumingtracingandrubbing,techniquesthatalsorequireahigh
level ofexpertise.Recentadvancesin3Dmodellingofnaturalobjectsandcomputationaltreatmentof
the modelledsurfacesmayprovideanalternative,andreducethecurrentdocumentationbottleneck.The
aim ofthisstudyistoexaminetheextenttowhichsuchtreatmentscanbeapplied.Thecasestudypre-
sented hereconcernsthefamousdeerstoneserectedbyancientMongoliannomadpopulations.The3D
acquisition workflowisbasedonstructure-from-motion,aversatilephotogrammetrictechnique,well
adapted tovariousfieldconditions.Fromthe3Dgeometryofobjectsofinterest,elevationrastermaps
are producedbyprojectiononfoursidesofthestela.Thesedigitalelevationmodelsarethentestedusing
algorithms basedondifferentialgeometry,skyvisibilityandlocalmorphology,thegeneralprinciples
of whicharebrieflyexposed.Alltheseapproachesmaybeappropriatewithessentiallyplanarsurfaces.
However, inthecaseofirregularcarvedsurfaces,suchasthoseofdeerstones,themostefficientalgorithm
appears tobepositiveopenness.Infavourablecases,theincisionscanbeautomaticallydelineated,facil-
itating thefinaldrawing.Resultsobtainedattheendoftheprocessarecomparabletothebestdrawings
available intheliterature,andcanalsoincludearchaeologicalinformationaboutrocksurfaceconditions.
The procedureconsiderablyacceleratestheworkflowincomparisonwithtraditionaltechniques,reduces
the levelofexpertiserequired,andprovides3Dmodels,whichcaneasilybeshared,orfurtheranalysed
by morphometricmethods,forinstance.
ing isessentiallyobtainedfromtime-consumingtracingandrubbing,techniquesthatalsorequireahigh
level ofexpertise.Recentadvancesin3Dmodellingofnaturalobjectsandcomputationaltreatmentof
the modelledsurfacesmayprovideanalternative,andreducethecurrentdocumentationbottleneck.The
aim ofthisstudyistoexaminetheextenttowhichsuchtreatmentscanbeapplied.Thecasestudypre-
sented hereconcernsthefamousdeerstoneserectedbyancientMongoliannomadpopulations.The3D
acquisition workflowisbasedonstructure-from-motion,aversatilephotogrammetrictechnique,well
adapted tovariousfieldconditions.Fromthe3Dgeometryofobjectsofinterest,elevationrastermaps
are producedbyprojectiononfoursidesofthestela.Thesedigitalelevationmodelsarethentestedusing
algorithms basedondifferentialgeometry,skyvisibilityandlocalmorphology,thegeneralprinciples
of whicharebrieflyexposed.Alltheseapproachesmaybeappropriatewithessentiallyplanarsurfaces.
However, inthecaseofirregularcarvedsurfaces,suchasthoseofdeerstones,themostefficientalgorithm
appears tobepositiveopenness.Infavourablecases,theincisionscanbeautomaticallydelineated,facil-
itating thefinaldrawing.Resultsobtainedattheendoftheprocessarecomparabletothebestdrawings
available intheliterature,andcanalsoincludearchaeologicalinformationaboutrocksurfaceconditions.
The procedureconsiderablyacceleratestheworkflowincomparisonwithtraditionaltechniques,reduces
the levelofexpertiserequired,andprovides3Dmodels,whichcaneasilybeshared,orfurtheranalysed
by morphometricmethods,forinstance.
OBJECTIVES: The true dwarf galagos of the genus Galagoides, G. demidoff and G. thomasi, are difficult to distinguish morphologically at a specific or subspecific level, and most taxonomic designations are based primarily on geographic... more
OBJECTIVES: The true dwarf galagos
of the genus Galagoides, G. demidoff and G. thomasi,
are difficult to distinguish morphologically at a specific
or subspecific level, and most taxonomic designations
are based primarily on geographic localities. We used
morphometrics to investigate the morphological diversity
of the genus.
MATERIALS AND METHODS: We conducted statistical
analyses of 12 linear measurements on 290 Galagoides
skulls housed in museums worldwide, and assembled
body weights for 71 wild caught specimens. We examined
sexual dimorphism and specific and subspecific distinctiveness
using MANOVA, ANOVA, principle
components analysis and canonical variate analysis.
RESULTS: We distinguished skulls identified as Galagoides
demidoff and G. thomasi with 70% reliability,
and demonstrated consistently different patterns of
static allometry in craniodental variables. Variables supporting
specific distinction included M1 width, palate
width at P2, palate (snout) length, length of premaxillary
tube, width across mastoids, and total skull length.
The type specimens of G. orinus and G. rondoensis were
significantly different from G. demidoff and G. thomasi,
but grouped with them in a CVA including G. zanzibaricus
and G. granti, although molecular studies indicate
that their true affiliation is with the latter species. Subspecies
within G. demidoff could not be distinguished
using craniodental morphometrics.
DISCUSSION: Galagoides demidoff and G. thomasi can
be distinguished relatively reliably, and are broadly
sympatric across western and central Africa. Neither species
showed evidence of sexual dimorphism in craniodental
size or shape. Size variation has a greater influence
on skull morphology in G. demidoff than it has
on G. thomasi.
of the genus Galagoides, G. demidoff and G. thomasi,
are difficult to distinguish morphologically at a specific
or subspecific level, and most taxonomic designations
are based primarily on geographic localities. We used
morphometrics to investigate the morphological diversity
of the genus.
MATERIALS AND METHODS: We conducted statistical
analyses of 12 linear measurements on 290 Galagoides
skulls housed in museums worldwide, and assembled
body weights for 71 wild caught specimens. We examined
sexual dimorphism and specific and subspecific distinctiveness
using MANOVA, ANOVA, principle
components analysis and canonical variate analysis.
RESULTS: We distinguished skulls identified as Galagoides
demidoff and G. thomasi with 70% reliability,
and demonstrated consistently different patterns of
static allometry in craniodental variables. Variables supporting
specific distinction included M1 width, palate
width at P2, palate (snout) length, length of premaxillary
tube, width across mastoids, and total skull length.
The type specimens of G. orinus and G. rondoensis were
significantly different from G. demidoff and G. thomasi,
but grouped with them in a CVA including G. zanzibaricus
and G. granti, although molecular studies indicate
that their true affiliation is with the latter species. Subspecies
within G. demidoff could not be distinguished
using craniodental morphometrics.
DISCUSSION: Galagoides demidoff and G. thomasi can
be distinguished relatively reliably, and are broadly
sympatric across western and central Africa. Neither species
showed evidence of sexual dimorphism in craniodental
size or shape. Size variation has a greater influence
on skull morphology in G. demidoff than it has
on G. thomasi.
Samples of one lichen species, Parmotrema crinitum, and one bromeliad species, Tillandsia usneoides, were collected in the state of Rio de Janeiro, Brazil, at four sites differently affected by anthropogenic pollution. The concentrations... more
Samples of one lichen species, Parmotrema
crinitum, and one bromeliad species, Tillandsia
usneoides, were collected in the state of Rio de Janeiro,
Brazil, at four sites differently affected by anthropogenic
pollution. The concentrations of aluminum, cadmium,
copper, iron, lanthanum, lead, sulfur, titanium, zinc, and
zirconiumwere determined by inductively coupled plasma–
atomic emission spectroscopy. The environmental
diagnosis was established by examining compositional
changes via perturbation vectors, an underused family
of methods designed to circumvent the problem of
closure in any compositional dataset. The perturbation
vectors between the reference site and the other three
sites were similar for both species, although body concentration
levels were different. At each site, perturbation
vectors between lichens and bromeliads were approximately
the same, whatever the local pollution level.
It should thus be possible to combine these organisms,
though physiologically different, for air quality
surveys, after making all results comparable with
appropriate correction. The use of perturbation vectors
seems particularly suitable for assessing pollution
level by biomonitoring, and for many frequently
met situations in environmental geochemistry, where
elemental ratios are more relevant than absolute
concentrations.
crinitum, and one bromeliad species, Tillandsia
usneoides, were collected in the state of Rio de Janeiro,
Brazil, at four sites differently affected by anthropogenic
pollution. The concentrations of aluminum, cadmium,
copper, iron, lanthanum, lead, sulfur, titanium, zinc, and
zirconiumwere determined by inductively coupled plasma–
atomic emission spectroscopy. The environmental
diagnosis was established by examining compositional
changes via perturbation vectors, an underused family
of methods designed to circumvent the problem of
closure in any compositional dataset. The perturbation
vectors between the reference site and the other three
sites were similar for both species, although body concentration
levels were different. At each site, perturbation
vectors between lichens and bromeliads were approximately
the same, whatever the local pollution level.
It should thus be possible to combine these organisms,
though physiologically different, for air quality
surveys, after making all results comparable with
appropriate correction. The use of perturbation vectors
seems particularly suitable for assessing pollution
level by biomonitoring, and for many frequently
met situations in environmental geochemistry, where
elemental ratios are more relevant than absolute
concentrations.
The publication of a well preserved Eocene primate, Darwinius masillae (Cercamoniinae, Notharctidae), has revived the debate on the phylogenetic relationships of Adapiformes and extant primates (Franzen et al., PLos ONE 4(5):e5723, 2009).... more
The publication of a well preserved Eocene primate,
Darwinius masillae (Cercamoniinae, Notharctidae), has
revived the debate on the phylogenetic relationships of
Adapiformes and extant primates (Franzen et al., PLos ONE
4(5):e5723, 2009). Recently, Lebrun et al. (J Anat 216:368–
380, 2010) showed that the morphology of the bony labyrinth
of strepsirrhine primates conveys a strong phylogenetic signal.
The study of labyrinthine morphology may thus bring a new
piece of evidence to resolve phylogenetic relationships within
a group. The investigation of the labyrinthine morphology of
another Cercamoniinae, Pronycticebus gaudryi, reveals no
synapomorphy with the labyrinths of modern anthropoids.
On the contrary, Pronycticebus is closer in labyrinthine shape
to extant strepsirrhines, which supports the hypothesis that the
Cercamoniinae and other Adapiformes are the sister group of
toothcombed primates.
Darwinius masillae (Cercamoniinae, Notharctidae), has
revived the debate on the phylogenetic relationships of
Adapiformes and extant primates (Franzen et al., PLos ONE
4(5):e5723, 2009). Recently, Lebrun et al. (J Anat 216:368–
380, 2010) showed that the morphology of the bony labyrinth
of strepsirrhine primates conveys a strong phylogenetic signal.
The study of labyrinthine morphology may thus bring a new
piece of evidence to resolve phylogenetic relationships within
a group. The investigation of the labyrinthine morphology of
another Cercamoniinae, Pronycticebus gaudryi, reveals no
synapomorphy with the labyrinths of modern anthropoids.
On the contrary, Pronycticebus is closer in labyrinthine shape
to extant strepsirrhines, which supports the hypothesis that the
Cercamoniinae and other Adapiformes are the sister group of
toothcombed primates.
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... more
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.
Warm temperatures decrease insect developmental time and body size. Social life could buffer external environmental variations, especially in large social groups, either through behavioral regulation and compensation or through specific... more
Warm temperatures decrease insect developmental time and body size. Social life could buffer external
environmental variations, especially in large social groups, either through behavioral regulation and compensation
or through specific nest architecture. Mean worker size and distribution of worker sizes within colonies are
important parameters affecting colony productivity as worker size is linked to division of labor in insect
societies. In this paper, we investigate the effect of stressful warm temperatures and the role of social
environment (colony size and size of nestmate workers) on the mean size and size variation of laboratory-born
workers in the small European ant Temnothorax nylanderi. To do so, we reared field-collected colonies under
medium or warm temperature treatments after having marked the field-born workers and removed the brood
except for 30 first instar larvae. Warm temperature resulted in the production of fewer workers and a higher
adult mortality, confirming that this regime was stressful for the ants. T. nylanderi ants followed the temperature
size rule observed in insects, with a decreased developmental time and mean size under warm condition. Social
environment appeared to play an important role as we observed that (i) larger colonies buffered the effect of
temperature better than smaller ones (ii) colonies with larger workers produced larger workers whatever the
rearing temperature and (iii) the coefficient of variation of worker size was similar in the field and under
medium laboratory temperature. This suggests that worker size variation is not primarily due to seasonal
environmental fluctuations in the field. Finally, we observed a higher coefficient of variation of worker size
under warm temperature. We propose that this results from a disruption of social regulation, i.e. the control of
nestmate workers over developing larvae and adult worker size, under stressful conditions.
environmental variations, especially in large social groups, either through behavioral regulation and compensation
or through specific nest architecture. Mean worker size and distribution of worker sizes within colonies are
important parameters affecting colony productivity as worker size is linked to division of labor in insect
societies. In this paper, we investigate the effect of stressful warm temperatures and the role of social
environment (colony size and size of nestmate workers) on the mean size and size variation of laboratory-born
workers in the small European ant Temnothorax nylanderi. To do so, we reared field-collected colonies under
medium or warm temperature treatments after having marked the field-born workers and removed the brood
except for 30 first instar larvae. Warm temperature resulted in the production of fewer workers and a higher
adult mortality, confirming that this regime was stressful for the ants. T. nylanderi ants followed the temperature
size rule observed in insects, with a decreased developmental time and mean size under warm condition. Social
environment appeared to play an important role as we observed that (i) larger colonies buffered the effect of
temperature better than smaller ones (ii) colonies with larger workers produced larger workers whatever the
rearing temperature and (iii) the coefficient of variation of worker size was similar in the field and under
medium laboratory temperature. This suggests that worker size variation is not primarily due to seasonal
environmental fluctuations in the field. Finally, we observed a higher coefficient of variation of worker size
under warm temperature. We propose that this results from a disruption of social regulation, i.e. the control of
nestmate workers over developing larvae and adult worker size, under stressful conditions.
European adapids, especially Adapis parisiensis, have been extensively studied over the past two centuries, essentially for taxonomic and phylogenetic purposes. Analyses of dental, cranial, and postcranial morphology have led to various... more
European adapids, especially Adapis parisiensis, have been extensively
studied over the past two centuries, essentially for taxonomic and phylogenetic
purposes. Analyses of dental, cranial, and postcranial morphology have led to
various hypotheses about the diet, locomotion, and lifestyle of this fossil primate
species. As the morphology of Adapis parisiensis is not directly comparable
to any extant species, some interpretations are still debated. The inner ear
is crucial to several functional parameters, such as auditory acuity, balance,
agility, orientation, and head motion speed during locomotion. We examined
the inner ear morphology of Adapis parisiensis in order to make some functional
inferences, using lCT techniques to access the internal morphology
without damaging the fossil specimens. We analyzed the length and shape of
the cochlea, the size of the oval window, and the size and orientation of the
semicircular canals of seven Adapis parisiensis crania. Results indicate that
the species was more sensitive to high frequencies than low frequencies.
Results for locomotion style are different, depending on the method used.
Results about the coefficient of agility are in good agreement with previous
studies, proposing a slow/medium slow locomotion for the fossil species. In contrast,
angular velocity magnitude (AVM) results show a great range of variation
in the locomotor repertory for Adapis parisiensis, probably indicating that
the model used is not adapted to the study of the fossil record. A comparison to
measurements of extant strepsirhines leads us to conclude that Adapis parisiensis
was probably monogamous and solitary, with a small home range.
studied over the past two centuries, essentially for taxonomic and phylogenetic
purposes. Analyses of dental, cranial, and postcranial morphology have led to
various hypotheses about the diet, locomotion, and lifestyle of this fossil primate
species. As the morphology of Adapis parisiensis is not directly comparable
to any extant species, some interpretations are still debated. The inner ear
is crucial to several functional parameters, such as auditory acuity, balance,
agility, orientation, and head motion speed during locomotion. We examined
the inner ear morphology of Adapis parisiensis in order to make some functional
inferences, using lCT techniques to access the internal morphology
without damaging the fossil specimens. We analyzed the length and shape of
the cochlea, the size of the oval window, and the size and orientation of the
semicircular canals of seven Adapis parisiensis crania. Results indicate that
the species was more sensitive to high frequencies than low frequencies.
Results for locomotion style are different, depending on the method used.
Results about the coefficient of agility are in good agreement with previous
studies, proposing a slow/medium slow locomotion for the fossil species. In contrast,
angular velocity magnitude (AVM) results show a great range of variation
in the locomotor repertory for Adapis parisiensis, probably indicating that
the model used is not adapted to the study of the fossil record. A comparison to
measurements of extant strepsirhines leads us to conclude that Adapis parisiensis
was probably monogamous and solitary, with a small home range.