Michel Baylac

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Sexual dimorphism of body size has been the subject of numerous studies, but few have examined sexual shape dimorphism (SShD) and its evolution. Allometry, the shape change associated with size variation, has been suggested to be a main component of SShD. Yet little is known about the relative importance of the allometric and non-allometric components for(More)
Traditional morphometrics, allozymes, and mitochondrial data have supported a close relationship between the M branch subspecies A. m. iberiensis and the North African subspecies (A branch). However, studies using nuclear DNA markers have revealed a clear distinction between the latter and the two European M branch subspecies. In help resolve this paradox,(More)
The parasitoid Hymenoptera contain a large number of species complexes that are as yet unresolved by traditional taxonomic studies. Evolutionary studies as well as biological control programmes often require further investigations which cannot rely on simple qualitative morphological characters; in many cases, particularly with dried specimens housed in(More)
Morphological integration and modularity within semi-autonomous modules are essential mechanisms for the evolution of morphological traits. However, the genetic makeup responsible for the control of variational modularity is still relatively unknown. In our study, we tested the hypothesis that the genetic variation for mandible shape clustered into two(More)
Heterochronic studies compare ontogenetic trajectories of an organ in different species: here, the skulls of common chimpanzees and modern humans. A growth trajectory requires three parameters: size, shape, and ontogenetic age. One of the great advantages of the Procrustes method is the precise definition of size and shape for whole organs such as the(More)
A common problem in the quantification of the orientation of the femoral neck is the difficulty to determine its true axis; however, this axis is typically estimated visually only. Moreover, the orientation of the femoral neck is commonly analysed using angles that are dependent on anatomical planes of reference and only quantify the orientation in two(More)
Understanding the three-dimensional orientation of the coxo-femoral joint remains a challenge as an accurate three-dimensional orientation ensure an efficient bipedal gait and posture. The quantification of the orientation of the acetabulum can be performed using the three-dimensional axis perpendicular to the plane that passes along the edge of the(More)
A new dance fly (Empididae: Empidinae) with hugely modified male fore tarsus, either on the right, left, both or neither sides, is described from Japan. Such massive polymorphic asymmetry occurring with so high an incidence in a population is previously unreported. In view of the courtship behaviour of other Empidinae, we hypothesize that the oversized(More)
The Enterobiinae includes 47 species of pinworms parasite of primates. A previous cladistic analysis of this subfamily supported its monophyly and its subdivision into three genera. Based on morphological characters, this cladistic analysis excluded characters describing the shape of the genital papillae of male pinworms, because the corresponding patterns(More)
The anatomical effects of artificial cranial deformation on the face and the base have been subject to various metric approaches, including standard linear as well as finite element techniques, and have produced controversial results (Antón [1989] Am. J. Phys. Anthropol. 79:253-267; Kohn et al. [1993] Am. J. Phys. Anthropol. 90:147-158). It can be argued(More)