Les changements culturels et techno-économiques majeurs survenus en Europe entre 7000 et 4000 ans... more Les changements culturels et techno-économiques majeurs survenus en Europe entre 7000 et 4000 ans avant J.-C., notamment le développement de l'agriculture, ont eu d’importantes répercussions sur les animaux qui vivaient près des hommes. Le chien, seul animal domestiqué depuis déjà plusieurs millénaires, est probablement un bon marqueur de l'évolution des sociétés humaines à cette époque. Bien que de nombreuses données nous informent sur son statut et sa diversité génétique, très peu d'études ont documenté sa variabilité morphologique et les éventuelles adaptations fonctionnelles en découlant, en lien avec les contraintes anthropiques. En outre, à ce jour, aucune étude n'a exploré la variabilité des renards roux anciens, bien qu'ils soient susceptibles de développer les mêmes adaptationsque les chiens (mais dans une moindre mesure en raison de leur nature commensale). Dans cette thèse, une approche morpho-fonctionnelle innovante est utilisée pour décrire l'évo...
Previous studies based on two-dimensional methods have suggested that the great morphological var... more Previous studies based on two-dimensional methods have suggested that the great morphological variability of cranial shape in domestic dogs has impacted bite performance. Here we use a three-dimensional biomechanical model based on dissection data to estimate the bite force of 47 dogs of various breeds at several bite points and gape angles. In vivo bite forces for three Belgian Shepherd dogs were used to validate our model. We then used three-dimensional geometric morphometrics to investigate the drivers of bite force variation and to describe the relations between the overall shape of the jaws and bite force. The model output shows that bite force is rather variable in dogs and that dogs bite harder on the molar teeth and at lower gape angles. Half of the bite force is determined by the temporal muscle. Bite force also increased with size, and brachycephalic dogs showed higher bite forces for their size than mesocephalic dogs. We obtained significant covariations between the shape...
Proceedings of the Royal Society B: Biological Sciences
Dogs are among the most variable species today, but little is known about the morphological varia... more Dogs are among the most variable species today, but little is known about the morphological variability in the early phases of their history. The Neolithic transition to farming may have resulted in an early morphological diversification as a result of changes in the anthropic environment or intentional selection on specific morphologies. Here, we describe the variability and modularity in mandible form by comparing 525 dog mandibles from European archaeological sites ranging from 8100 to 3000 cal. BC to a reference sample of modern dogs, wolves, and dingoes. We use three-dimensional geometric morphometrics to quantify the form of complete and fragmented mandibles. We demonstrate that an important morphological variability already existed before the Bronze Age in Europe, yet the largest, smallest, most brachycephalic or dolichocephalic extant dogs have no equivalent in the archaeological sample, resulting in a lower variation compared to modern relatives. The covariation between the...
Les changements culturels et techno-économiques majeurs survenus en Europe entre 7000 et 4000 ans... more Les changements culturels et techno-économiques majeurs survenus en Europe entre 7000 et 4000 ans avant J.-C., notamment le développement de l'agriculture, ont eu d’importantes répercussions sur les animaux qui vivaient près des hommes. Le chien, seul animal domestiqué depuis déjà plusieurs millénaires, est probablement un bon marqueur de l'évolution des sociétés humaines à cette époque. Bien que de nombreuses données nous informent sur son statut et sa diversité génétique, très peu d'études ont documenté sa variabilité morphologique et les éventuelles adaptations fonctionnelles en découlant, en lien avec les contraintes anthropiques. En outre, à ce jour, aucune étude n'a exploré la variabilité des renards roux anciens, bien qu'ils soient susceptibles de développer les mêmes adaptationsque les chiens (mais dans une moindre mesure en raison de leur nature commensale). Dans cette thèse, une approche morpho-fonctionnelle innovante est utilisée pour décrire l'évo...
Previous studies based on two-dimensional methods have suggested that the great morphological var... more Previous studies based on two-dimensional methods have suggested that the great morphological variability of cranial shape in domestic dogs has impacted bite performance. Here we use a three-dimensional biomechanical model based on dissection data to estimate the bite force of 47 dogs of various breeds at several bite points and gape angles. In vivo bite forces for three Belgian Shepherd dogs were used to validate our model. We then used three-dimensional geometric morphometrics to investigate the drivers of bite force variation and to describe the relations between the overall shape of the jaws and bite force. The model output shows that bite force is rather variable in dogs and that dogs bite harder on the molar teeth and at lower gape angles. Half of the bite force is determined by the temporal muscle. Bite force also increased with size, and brachycephalic dogs showed higher bite forces for their size than mesocephalic dogs. We obtained significant covariations between the shape...
Proceedings of the Royal Society B: Biological Sciences
Dogs are among the most variable species today, but little is known about the morphological varia... more Dogs are among the most variable species today, but little is known about the morphological variability in the early phases of their history. The Neolithic transition to farming may have resulted in an early morphological diversification as a result of changes in the anthropic environment or intentional selection on specific morphologies. Here, we describe the variability and modularity in mandible form by comparing 525 dog mandibles from European archaeological sites ranging from 8100 to 3000 cal. BC to a reference sample of modern dogs, wolves, and dingoes. We use three-dimensional geometric morphometrics to quantify the form of complete and fragmented mandibles. We demonstrate that an important morphological variability already existed before the Bronze Age in Europe, yet the largest, smallest, most brachycephalic or dolichocephalic extant dogs have no equivalent in the archaeological sample, resulting in a lower variation compared to modern relatives. The covariation between the...
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Papers by Colline Brassard