Titre du document / Document title

A geometric morphometric assessment of the effects of environment and cladogenesis on the evolution of the turtle shell

Auteur(s) / Author(s)

CLAUDE Julien ⁽¹⁾ ; PARADIS Emmanuel ⁽¹⁾ ; HAIYAN TONG ; AUFFRAY Jean-Christophe ⁽¹⁾ ;

Affiliation(s) du ou des auteurs / Author(s) Affiliation(s)

⁽¹⁾ Institut des Sciences de l'Evolution, Université de Montpellier 2, UMR 5554 CNRS, Cc 064, 2, Place Eugène Bataillon, 34095 Montpellier, FRANCE

Résumé / Abstract

In the largest group of extant turtles, the Testudinoidea, the acquisition of an aquatic or terrestrial way of life has occurred within two clades, allowing the study of homoplasy linked to environment (commonly named convergence). Here we appraise the respective importance of two sources of morphological variation: a major cladogenetic event and a major environmental shift (aquatic vs. terrestrial). The repeatability of the same evolutionary process (environmental change) allows an assessment of the weights of both natural selection and phylogenetic constraints on several morphological features of the shell. These sources of morphological variance on the complex shell structure were studied using geometric morphometrics. We depict the morphological variation of three parts of the turtle shell: epidermal carapace, bony carapace, and plastron. In the three structures, we found that both phylogeny and environment were significant sources of morphological variation, and geometric morphometrics allowed the pattern of morphological variation due to each effect to be assessed. The assessment of the homoplasy due to environment and of the pattern of morphological variability suggests that the carapace has undergone similar morphological changes between aquatic and terrestrial environments within the two clades. The radiation of the Testudinoidea is interpreted as an adaptive radiation.

Revue / Journal Title

Biological Journal of the Linnean Society   ISSN 0024-4066   CODEN BJLSBG 

Source / Source

2003, vol. 79, n^o3, pp. 485-501 [17 page(s) (article)] (1 p.3/4)

Langue / Language

Anglais

Editeur / Publisher

Blackwell, Oxford, ROYAUME-UNI  (1969) (Revue)

Mots-clés anglais / English Keywords

Vertebrata ; Reptilia ; Chelonia ; Phylogeny ; Natural selection ; Adaptive radiation ; Morphology ; Biological evolution ; Environmental factor ; Carapace ; Geometry ; Morphometry ;

Mots-clés français / French Keywords

Vertebrata ; Reptilia ; Chelonia ; Testudinoidea ; Phylogenèse ; Sélection naturelle ; Radiation adaptative ; Morphologie ; Evolution biologique ; Facteur milieu ; Carapace ; Géométrie ; Morphométrie ;

Mots-clés espagnols / Spanish Keywords

Vertebrata ; Reptilia ; Chelonia ; Filogénesis ; Selección natural ; Radiación adaptativa ; Morfología ; Evolución biológica ; Factor medio ; Exoesqueleto ; Geometría ; Morfometría ;

Localisation / Location

INIST-CNRS, Cote INIST : 1099, 35400011997302.0050