Rate of gene sequence evolution and species diversification in flowering plants: a re-evaluation.

摘要

Barraclough and co-workers [Proceedings of the Royal Society of London. Series B (1996) 263, 589-591] observed that there was a significant positive correlation between the rate of evolution of the rbcL chloroplast gene within families of floweringplants and the number of species in those families. Three additional data sets (based on both plastid and nuclear genes) were tested using methods designed specifically for the comparison of sister families (based on random speciation and extinction). Itwas shown that, over all sister groups, the correlation between the rate of gene evolution and an increased diversity is not always present. Despite tending towards a positive association, the observation of individual probabilities presents a U-shapeddistribution of association (i.e. it can be either significantly positive or negative). The influence of both phylogenetic sampling and applied taxonomies on the results are discussed.