Biotic vs abiotic factors promoting the diversification of caenophidian snakes.

人们普遍认为，高级蛇（Caenophidia）的进化多样化在新近纪经历了一次重大爆发，但这种多样化增加的原因仍然知之甚少。已经提出了几个因果假设，从捕食者-猎物共同进化的场景到新生代气候变化。在这里提出的项目中，我们希望用一种包括化石和分子信息的综合方法来检验这些假设：a)我们将包括一个全面的化石蛇的数据集，我们将结合分子分化估计来计算新生代物种形成和灭绝的速度；B)使用相同的方法，我们将通过将我们的结果与哺乳动物、鸟类、两栖动物和有鳞动物的多样化模式进行比较，来测试与猎物分类群的相关性；C)使用先进的生物信息学方法，我们将测试嗜蛇的多样化是否是一个关键创新的结果；d)以C4禾本科植物为代表，比较新生代气候变化对林木多样性的影响。这种综合的方法最终将使我们能够确定Caenophidian蛇令人印象深刻的进化成功的最有可能的原因。

It is widely believed that the evolutionary diversification of advanced snakes (Caenophidia) experienced a major burst in the Neogene, but the causes for this increase in diversification remain poorly understood. Several causal hypotheses have been suggested, ranging from predator-prey coevolutionary scenarios to Cenozoic climate change. In the here proposed project we wish to test these hypotheses using an integrative approach comprising both fossil and molecular information: a) We will comprise a comprehensive data set of fossil caenophidian snake occurrences, which we use in conjunction with molecular divergence estimates to calculate rates of speciation and extinction through the Cenozoic; b) using the same approach, we will test for correlations with prey taxa by comparing our results with diversification patterns in mammals, birds, amphibians, and squamates; c) using advanced bioinformatic approaches we will test if caenophidian snake diversification is the result of a key innovation; d) using C4 grasses as a proxy, we will compare Caenophidian diversification rates to Cenozoic climate history. This comprehensive approach will finally allow us to determine the most likely causes for the impressive evolutionary success of Caenophidian snakes.