Aim The intricate puzzle-like geography of the western Mediterranean is a product of long-term tectonic and orogenic events, supplemented by repeated climatic oscillations since the Pliocene. It offers numerous vicariance events that may be invoked to explain speciation in amphibians. We test for plausibility of two mutually exclusive Iberian-African vicariance hypotheses to explain the basal split within newts of the genus Pleurodeles: (1) the disconnection of the Betic arch c. 14 Ma and (2) the end of the Messinian salinity crisis 5.33 Ma.Location Specimens of P. waltl and P. poireti were sampled from 32 populations in Portugal, Spain, Morocco, Algeria and Tunisia.Methods Parts of three mitochondrial genes were sequenced (16S rRNA, cytochrome b, ATPase). Based on substitution rate constancy among lineages three different molecular clocks were calibrated to derive competing evolutionary scenarios for lineage evolution within Pleurodeles.Results One scenario was aligned with the dated fossil record and with historical events that are known to have enabled terrestrial faunal exchange between Europe and Africa. In Pleurodeles, such faunal exchange is more likely to have happened three times, resulting in the current pattern of species diversity and haplotype distribution: (1) following the disconnection of the Betic region from Iberia and connection of its southernmost part (present-day Rif Mountains) to Africa, c. 14 Ma; (2) closing of the Strait of Gibraltar prior to the Messinian salinity crisis, 5.59-5.33 Ma; (3) passive dispersal in recent times, caused by rafting on vegetation or inadvertent displacement by man. The results show that North African P. poireti populations comprise two distinct lineages; despite their geographical proximity, haplotype distribution within both lineages indicates totally different histories (range fragmentation vs. dispersal).Main conclusions Ribbed salamanders mainly evolved through allopatric speciation, driven by vicariance events. However, faunal exchange between Europe and Africa at the western end of the Mediterranean basin was linked to well-known events of physical contact between both continents. This sheds new light on the potential role of dispersal across marine barriers via rafting or even, presumably inadvertent, anthropogenic displacement for the initiation of speciation in amphibians.
This is the first continent‐wide overview of insect diversity and status sufficiently fine‐scaled to be used in conservation planning. We analyze patterns of richness and the conservation status of African dragonflies and damselflies (Insecta: Odonata), commonly referred to as dragonflies, to determine threats to species and freshwater habitats, location of diversity hotspots, necessary conservation actions, and research gaps. Major centers of dragonfly diversity in Africa are tropical forest areas that include highlands. Most threatened species – as classified by the International Union for Conservation of Nature global Red List – are concentrated in highlands from Kenya to South Africa (together with the Cape Floristic Region), western Africa (including mountains on the Cameroon–Nigeria border), and Ethiopia. Currently available knowledge can be applied throughout Africa's freshwater systems to help minimize or mitigate the impact of future development actions, allowing dragonflies to act as “guardians of the watershed”. The private sector can be advised to safeguard sensitive habitats and species when selecting sites for development. Key sites and species for monitoring can be identified by checking the distribution of threatened species at http://www.iucnredlist.org.
The greater flamingo Phoenicopterus roseus is a long‐lived colonial waterbird species, characterized by a large range encompassing three continents, a very limited number of breeding sites, and high dispersal abilities. We investigated both the phylogeographic history and the contemporary extent of genetic differentiation between eight different Mediterranean breeding colonies of greater flamingos sampled between 1995 and 2009, using both mitochondrial DNA and microsatellite markers. We found no significant differences in allelic richness or private allelic richness in relation to colony size. Overall, no genetic population differentiation was detected using either mitochondrial or microsatellite markers. F‐statistics and Bayesian clustering methods did not support any significant genetic structure. Analysis of both mitochondrial DNA and microsatellites indicated that populations have undergone a bottleneck followed by rapid growth and expansion. The average time since expansion was estimated to be 696 421 yr (90% CI: 526 316–1 131 579 yr). We discuss our results in relation to both the possible historical events accounting for the present genetic structure and relevance to conservation and management of the species.
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