2009/07/16 by Ylenia Chiari, Chaz Hyseni, Tom H. Fritts +5 · 3 citations
Environmental Science · Biochemistry, Genetics and Molecular Biology · #Turtle Biology and Conservation #Genetic diversity and population structure #Wildlife Ecology and Conservation #Biology #Morphometrics #Population #Evolutionary biology #Phylogeography #Tortoise #Zoology #Lineage (genetic) #Population genetics #Genetic structure #Taxon #Genetic variation #Phylogenetics #Ecology #Genetics
paper · pdf · doi:10.1371/journal.pone.0006272
openalex publication_date 2009/07/16 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Galápagos tortoises represent the only surviving lineage of giant tortoises that exhibit two different types of shell morphology. The taxonomy of Galápagos tortoises was initially based mainly on diagnostic morphological characters of the shell, but has been clarified by molecular studies indicating that most islands harbor monophyletic lineages, with the exception of Isabela and Santa Cruz. On Santa Cruz there is strong genetic differentiation between the two tortoise populations (Cerro Fatal and La Reserva) exhibiting domed shell morphology. Here we integrate nuclear microsatellite and mitochondrial data with statistical analyses of shell shape morphology to evaluate whether the genetic distinction and variability of the two domed tortoise populations is paralleled by differences in shell shape. Based on our results, morphometric analyses support the genetic distinction of the two populations and also reveal that the level of genetic variation is associated with morphological shell shape variation in both populations. The Cerro Fatal population possesses lower levels of morphological and genetic variation compared to the La Reserva population. Because the turtle shell is a complex heritable trait, our results suggest that, for the Cerro Fatal population, non-neutral loci have probably experienced a parallel decrease in variability as that observed for the genetic data.