Studies in evolutionary biology have commonly been focused on insular systems because of their natural geographic isolation and relatively simpler biotas. Using mitochondrial DNA sequences of 4 passerine bird species distributed in the Tres Marías Archipelago (TMA) and the nearby mainland of western Mexico—Cardinalis cardinalis, Turdus rufopalliatus, Vireo hypochryseus, and Icterus pustulatus—we determined interspecific and intraspecific phylogenetic relationships between insular and mainland populations, conducted insular age-based time calibration for the estimation of divergence times, and used Bayesian analyses to examine the colonization history of islands. Specifically, we tested whether the study species from the TMA share the same colonization history since the emergence of the islands ∼120 kya, taking advantage of the reduced isolation due to sea-level fluctuations during the Pleistocene, or whether there were independent colonization events. We also looked for evidence in the genetic structure of the island populations that would support the idea of colonization by a small number of individuals. Phylogenetic relationships consistently recovered lineage divergence between the TMA and mainland populations, with strong support in 3 of the 4 species. Our estimates for the sea level and coastline of the west coast of Mexico during the Pleistocene showed that the distance between the TMA and the mainland was ∼25 km. We tested several island colonization scenarios according to the phylogenetic relationships, haplotype networks, divergence time estimates, historical demography, and different glaciation dates. The most supported scenario of colonization of the TMA suggests that a single event occurred ∼120 kya when the islands emerged, which is highly concordant with geological evidence, and simultaneously affected the 4 species.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.