A review of phylogeographic analyses of animal taxa from the Aegean and surrounding regions

Abstract

We provide a review and synthesis of key findings in phylogeographic research on terrestrial animals in the Aegean archipelago (Greece) and surrounding regions (Greek mainland, southern Balkans and Asia Minor). A critical review of more than 100 phylogeographic articles on 76 animal genera (30 invertebrates and 46 vertebrates) that have been published so far for the region leads to the recognition of three types of distribution patterns: old ‘colonizers’ diversified in the Aegean before the formation of the mid-Aegean Trench (MAT – i.e. before 9 Mya), post-MAT colonizers that arrived to the Aegean in late Miocene and Pliocene and new colonizers that inhabited the region in the Pleistocene or even the Holocene. Several problems, mainly regarding the use of calibration points and/or molecular clock rates for clade chronology, have been identified in many analyses. Despite the large amount of phylogeographic work concerning the Aegean and surrounding regions, many groups remain unstudied (especially invertebrates, micro-organisms, fungi and plants), and many issues still remain unresolved. The relative roles of extinction, speciation, dispersal and vicariance, as well as the effects of adaptive and non-adaptive components of diversification, need further analyses with modern tools that can provide deeper insights. A more detailed reconstruction of the palaeogeography of the region is also of prime importance. The critical views presented herein may prove useful also for the evaluation of similar work in other regions.