The aim is to highlight, in a phylogenetic context, the effect of environmental constraints and way of life on the shape of different cetacean species. Although cetaceans all possess a streamlined and hydrodynamic body due to their aquatic environment, their phenotypes vary widely among species according to their different lifestyle. The main hypothesis is that the morphology supporting performances must be in relation with the species habitat; it should be possible to infer the lifestyle of an animal on the basis of its phenotype. This research project consists of a multidisciplinary approach which aims to collect data about morphology, locomotion and ecology of different cetacean species to understand why such a diversity of shape exists in this clade.
The project is divided into four main tasks. The two first tasks aim at comparing axial skeletons and fin shape of a large number of cetacean species by using meristic, morphometric and geomorphometric data to identify different morphological groups and advance hypotheses about their swimming style and mode of life. The purpose of the third task is to define different swimming styles by collecting data about flexion points of the body of different species during swimming and then to link the morphological characteristics with the functional diversity. Finally, all these characters will be studied in the general framework of existing phylogenetic trees in order to understand how variations of the swimming movements and the anatomy of the skeleton and the fins allowed the exploitation of different ecological zones.