Presenter: Prof. Carlos Juan, Universitat de les Illes Balears

Time:10:00, May 19, 2010 Wed

Locale: B105, Institute of Zoology

Abstract:

In the last 15 years we have witnessed a true explosion of evolutionary studies using molecular markers on Canary Islands plants, invertebrates and vertebrates that have changed the paradigm of a “relict flora” and, in some cases fauna, to a relatively recent diversification pattern in many taxonomic groups. Phylogeographic analyses have also shown that volcanic cycles have shaped common patterns of genetic variation and clarify many of the diversification processes both at the whole archipelago and single island levels. In this talk I will summarize some of our work on beetles, grasshoppers and amphipods, the latter adapted to the volcanic subterranean environment. Evolutionary studies of subterranean taxa are frequently limited by the lack of extant surface-dwelling (epigean) close relatives. Thus, there is a need for simple case-study models where recently evolved subterranean populations coexist with their presumed epigean ancestors, as the early stages of the evolution of ancient subterranean taxa are difficult to reconstruct. In our model species, the terrestrial amphipod Palmorchestia in the island of La Palma, mitochondrial sequences have revealed strong phylogeographic structuring and near absence of gene flow within or between cave and epigean populations, providing also evidence that the lava tubes have been invaded multiple times.