02135nas a2200217   4500008004100000245007500041210006900116260001600185300001200201490000800213520150600221100001801727700002101745700002001766700002201786700001501808700002101823700001801844700002001862856003501882       2007                        eng d00aGlobal patterns of diversification in the history of modern amphibians0 aGlobal patterns of diversification in the history of modern amph  cJan 16 2007  a887-8920 v1043 aThe fossil record of modern amphibians (frogs, salamanders, and caecilians) provides no evidence for major extinction or radiation episodes throughout most of the Mesozoic and early Tertiary. However, long-term gradual diversification is difficult to reconcile with the sensitivity of present-day amphibian faunas to rapid ecological changes and the incidence of similar environmental perturbations in the past that have been associated with high turnover rates in other land vertebrates. To provide a comprehensive overview of the history of amphibian diversification, we constructed a phylogenetic timetree based on a multigene data set of 3.75 kb for 171 species. Our analyses reveal several episodes of accelerated amphibian diversification, which do not fit models of gradual lineage accumulation. Global turning points in the phylogenetic and ecological diversification occurred after the end-Permian mass extinction and in the late Cretaceous. Fluctuations in amphibian diversification show strong temporal correlation with turnover rates in amniotes and the rise of angiosperm-dominated forests. Approximately 86% of modern frog species and > 81% of salamander species descended from only five ancestral lineages that produced major radiations in the late Cretaceous and early Tertiary. This proportionally late accumulation of extant lineage diversity contrasts with the long evolutionary history of amphibians but is in line with the Tertiary increase in fossil abundance toward the present.1 aRoelants, Kim1 aGower, David, J.1 aWilkinson, Mark1 aLoader, Simon, P.1 aBiju, S.D.1 aGuillaume, Karen1 aMoriau, Linde1 aBossuyt, Franky  u<Go to ISI>://PREV200700290016