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.

The Sawflies of Crete (Hymenoptera, Symphyta)

“…On the contrary, a tendency noticeable in many recent works (e.g. Poulakakis et al 2014) is to ascribe greater importance than previously to the shaping of the modern fauna and flora of Crete by human activities compared with natural events.…”

“…Unfortunately, we do not yet have sufficient genetic data to test this. The introduction of species to areas outside their natural range leads to homogenisation of faunas, obscuring biogeographic patterns (Poulakakis et al 2014).…”

“…Poulakakis et al (2014) reviewed the current state of knowledge of the phylogeography of animal taxa in the Aegean and surrounding areas and recognised four main patterns of colonisation. The first of these includes species present before the formation of the mid-Aegean Trench, more than 9 million years ago.…”

Phylogeny, phylogeography, and evolution in the Mediterranean region: News from a freshwater mussel (Potomida, Unionida)

“…4). The alternative scenario is a colonization during the connection of the Hellenic Peninsula and Anatolia in the upper Miocene, i.e., before the MSC (Economou et al, 2007;Poulakakis et al, 2015). However, this seems unlikely since the age of this event falls outside the confidence interval for the semirugata-acarnanica divergence.…”

“…However, the timing is still controversial, as are processes that have led to the key assemblage components of each biogeographic region (Bȃnȃrescu, 2004;Gaubert et al, 2009). The biogeographical boundary of the mid-Aegean trench separating Anatolia from Southern Greece is long established (Poulakakis et al, 2015;Zogaris et al, 2009), but dispersal of freshwater organisms may have occurred either during the MSC or even at an earlier land contact event. Tsigenopoulos et al (2003) hypothesised that during the MSC a network of interconnected rivers facilitated dispersal of the cyprinid genus Luciobarbus across the dried Mediterranean.…”