Introduction

Abstract

During the evolution of vertebrates, various locomotor patterns such as swimming, walking, running, jumping, flying and burrowing were developed (ten Donkelaar 1999). Each of these diverse vertebrate locomotor modes is derived from the fundamental swimming pattern, i.e., lateral undulation, present in most aquatic chordates. Paired fins did not evolve until later. When the land vertebrates arose, the lateral paired fins were converted into organs of locomotion, on the ground or in the air. Finally, particularly in primates, modifications of the distal parts of the extremities (usually the forelimbs) allowed the manipulation of the environment.