INVESTIGADORES
AVILA luciano Javier
congresos y reuniones científicas
Título:
How lizards survived blizzards: phylogeography of the Liolaemus lineomaculatus group (Liolaemini) reveals multiple breaks and refugia in southern Patagonia, and their concordance with other co-distributed taxa
Autor/es:
BREITMAN, M.F.; AVILA, L.J.; PARRA, M.; SITES, J.W., JR.; MORANDO, M.
Lugar:
Vancouver
Reunión:
Congreso; VII World Congress of Herpetology; 2012
Institución organizadora:
World Congress of Herpetology
Resumen:
Patagonia was shaped by a complex geological history, including the Miocene uplift of the Andes, followed by volcanism, marine introgressions, and extreme climatic oscillations during Pleistocene glaciation?deglaciation cycles. The distributional patterns and phylogenetic relationships of Patagonian animals and plants were affected in different ways, and those imprints are reflected in the seven phylogeographic breaks and eight refugia that have been proposed from phylogeographic studies of some plant and rodent clades of southern Patagonia. In this study we estimated time-calibrated phylogenetic/phylogeographic patterns in lizards of the Liolaemus lineomaculatus group, and related them to historical Miocene-to-Pleistocene events of Patagonia and the previously proposed patterns summarized from earlier studies. We also found evidence for candidate species, and quantified phenotypic differences among them. I ndividuals from 51 localities were sequenced for two mitochondrial (cyt- b and 12S) and one nuclear (KIF24) gene regions. Our analyses revealed strong phylogeographic structure among lineages and, in most cases, no signal of population changes through time. The lineomaculatus group is composed of three strongly supported clades ( lineomaculatus, hatcheri and kolengh+silvanae ), and divergence estimates suggested that their origins may have been associated with the oldest known Patagonian glaciation (7-5 Ma), while subsequent diversification within the lineomaculatus clade coincided with the large Pliocene glaciations (~3.5 Ma). The lineomaculatus clade lineages are strongly structured genetically and geographically and are interpreted (with caveats) as young candidate species showing various levels of morphological differentiation. Our findings suggest that some Liolaemus lineages have persisted in situ in multiple refugia through several glaciation- deglaciation cycles in southern Patagonia without demographic fluctuations. We also provide qualitative evidence of some shared phylogeographic breaks and refugia among plants, rodents, and lizards.