出版社:International Academy of Ecology and Environmental Sciences
摘要:The Tropical Conservativism Hypothesis suggests processes of speciation, extinction and dispersal resulted in higher species richness at the tropics and declined away from the equator. Biogeographical Conservativism Hypothesis suggests that the processes invoked are not intrinsic to the tropics but were dependent on historical biogeography to determine the distribution of species richness. 77 valid species were identified as belonging to the genus Gnomeskelus in order to test between the two hypotheses. There was a significant correlation between the number of species and latitudinal degrees away from the equator (r=-0.7145, r2 =0.5105, n=77, p<0.00001). Alternatively, there may be an evolutionary preference for temperate environments appearing to have led to climatic constraints on dispersal based primarily on temperature seasonality gradients.