Identifying genetic lineages through shape: An example in a cosmopolitan marine turtle species using geometric morphometrics

Autoři: Rocío Álvarez-Varas aff001;  David Véliz aff001;  Gabriela M. Vélez-Rubio aff003;  Alejandro Fallabrino aff003;  Patricia Zárate aff005;  Maike Heidemeyer aff006;  Daniel A. Godoy aff009;  Hugo A. Benítez aff010
Působiště autorů: Departamento de Ciencias Ecológicas, Facultad de Ciencias, Universidad de Chile, Santiago, Chile aff001;  Núcleo Milenio de Ecología y Manejo Sustentable de Islas Oceánicas (ESMOI), Departamento de Biología Marina, Universidad Católica del Norte, Coquimbo, Chile aff002;  Karumbé NGO, Montevideo, Uruguay aff003;  Centro Universitario Regional del Este (CURE), Sede Rocha, Universidad de la República, Rocha, Uruguay aff004;  Departamento de Oceanografía y Medio Ambiente, Instituto de Fomento Pesquero, Valparaíso, Chile aff005;  Centro de Investigación en Biología Celular y Molecular (CIBCM), Universidad de Costa Rica, San Pedro, San José, Costa Rica aff006;  Centro de Investigación en Ciencias del Mar y Limnología (CIMAR), Universidad de Costa Rica, San Pedro, San José, Costa Rica aff007;  Asociación para la Conservación Integral de Recursos Naturales Equipo Tora Carey (ETC), El Jobo, La Cruz, Guanacaste, Costa Rica aff008;  Coastal-Marine Research Group, Institute of Natural and Mathematical Sciences, Massey University, Auckland, New Zealand aff009;  Departamento de Biología, Facultad de Ciencias, Universidad de Tarapacá, Arica, Chile aff010
Vyšlo v časopise: PLoS ONE 14(10)
Kategorie: Research Article


The green turtle (Chelonia mydas) is a globally distributed marine species whose evolutionary history has been molded by geological events and oceanographic and climate changes. Divergence between Atlantic and Pacific clades has been associated with the uplift of the Panama Isthmus, and inside the Pacific region, a biogeographic barrier located west of Hawaii has restricted the gene flow between Central/Eastern and Western Pacific populations. We investigated the carapace shape of C. mydas from individuals of Atlantic, Eastern Pacific, and Western Pacific genetic lineages using geometric morphometrics to evaluate congruence between external morphology and species’ phylogeography. Furthermore, we assessed the variation of carapace shape according to foraging grounds. Three morphologically distinctive groups were observed which aligned with predictions based on the species’ lineages, suggesting a substantial genetic influence on carapace shape. Based on the relationship between this trait and genetic lineages, we propose the existence of at least three distinct morphotypes of C. mydas. Well-defined groups in some foraging grounds (Galapagos, Costa Rica and New Zealand) may suggest that ecological or environmental conditions in these sites could also be influencing carapace shape in C. mydas. Geometric morphometrics is a suitable tool to differentiate genetic lineages in this cosmopolitan marine species. Consequently, this study opens new possibilities to explore and test ecological and evolutionary hypotheses in species with wide morphological variation and broad geographic distribution range.

Klíčová slova:

Evolutionary genetics – Foraging – Genetic polymorphism – Chile (country) – Marine geology – Phylogeography – Turtles – Pacific Ocean


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