News from IBE (CSIC-UPF)
The Socotra Archipelago, four small islands in the Indian ocean and nowadays belonging to Yemen, is one of the most difficult to access and distinct archipelagos in the world. The long isolation period from continental Arabia (around 20 million years ago) together with its topography and its high ecological and climatic diversity, create an exclusive and spectacular endemic fauna and flora found nowhere else on earth.
Now, a work led by CSIC scientists and published in the journal PLOS ONE, unveils that over 50% of reptile species in Socotra could be still undiscovered. The work is a result of sequencing a small part of the mitochondrial gene cytochrome oxidase (COI) in a large number of samples from the Socotra Archipelago.
Since 2010, the team led by Salvador Carranza, senior researcher at the IBE (CSIC-UPF) in Barcelona, has conducted several expeditions to Socotra in order to collect samples of all known species and localities. For each sample, they have sequenced a small region of the COI gene and then compared it among each other. This gene is shared among all animals, since it is linked to essential life functions. It has enough variation to allow discrimination between species. This gene, points out Carranza, has a very fast evolution rate. This means that when two populations of animals split up, stopping mating and reproducing, the gene differentiates and evolves quickly. Such differences allow us to distinguish different species.
IBE (CSIC-UPF) Website
Unexpectedly High Levels of Cryptic Diversity Uncovered by a Complete DNA Barcoding of Reptiles of the Socotra Archipelago. Vasconcelos, Raquel; Montero-Mendieta, Santiago; Simó-Riudalbas, Marc; Sindaco, Roberto; Santos, Xavier et al. (2016) PloS One. vol. 11 (3) p. e0149985