Seasonality and Temperature:Turtles in Hot Water?

Variation in temperature affects the biology of sea turtles at a range of scales. To elucidate the drivers of seasonality of nesting and duration of season, databases across four species of sea turtles (Caretta caretta n=37, Chelonia mydas n=64, Dermochelys coriacea n=44 and Eretmochelys imbricata n=36) at a global scale were created. By using remotely sensed sea surface temperature data, thermal profiles across the nesting season were generated. Duration of nesting season was correlated with latitude in all species but was more tightly coupled with temperature; seasons were significantly longer with increased mean SST. In general, nesting seasonality occurred at warmest time of the year. SST for the month before, month after and the month of peak nesting significantly affected the month of peak nesting.

Genetic Differentiation of the Cabo Verde Archipelago Population Analysed by STR Polymorphisms

Allele frequencies for 17 STR loci were analyzed in a sample of unrelated males from the Cabo Verde Archipelago. The samples were gathered in such a way that the origin of the subjects was perfectly identified, and they could be included in one of the leeward or windward groups of islands. This study reveals that there are significant differences between both groups of islands, and between Cabo Verdeans and other populations from sub-Sahara Africa including the Guineans, the most probable source population for Cabo Verdeans. This study confirms mtDNA data and, together with HLA and Y chromosome data already published, shows that the Cabo Verde population is substructured and atypical, diverging substantially from mainland sub-Saharan populations. Overall these differences are most probably due to admixture between sub-Saharan slaves brought into the islands and other settlers of European origin. In the absence of a clear indication of a different ethnic composition of the first sub-Saharan settlers of Cabo Verde, the differentiation exhibited in both groups of islands can be most probably be attributed to genetic drift.