The evolution of skilled forelimb movements in carnivorans

Abstract

Emancipating the forelimbs from locomotion for use in other activities, such as food manipulation, is a major evolutionary milestone. A variety of selective forces and evolutionary correlates may influence the evolution of various degrees of skill with which the forelimbs are used. Using the order Carnivora as a test group, I assesed the relative influence of six factors: relative brain size, neocortical volume, manus proportions, body size, phylogenetic relatedness, type of locomotion and diet. I developed a rating system to describe the dexterity of individual species and compared the scores to the six factors using modern comparative methods. Only phylogeny and diet were significanly correlated with forelimb dexterity. More specifically, forelimb dexterity tends to be higher in caniform than in feliform carnivorans and decreases with increasing specialisation on vertebrate prey. I conclude that food handling and feeding niche breath have a significant effect upon the evolution of skilled forelimb movements.