Data from: A phylogenetic analysis of macroevolutionary patterns in fermentative yeasts

When novel sources of ecological opportunity are available, physiological innovations can trigger adaptive radiations. This could be the case of yeasts (Saccharomycotina), in which an evolutionary novelty is represented by the capacity to exploit simple sugars from fruits (fermentation). During adaptive radiations, diversification and morphological evolution are predicted to slow-down after early bursts of diversification. Here, we performed the first comparative phylogenetic analysis in yeasts, testing the “early burst” prediction on species diversification and also on traits of putative ecological relevance (cell-size and fermentation versatility). We found that speciation rates are constant during the time-range we considered (ca., 150 millions of years). Phylogenetic signal of both traits was significant (but lower for cell-size), suggesting that lineages resemble each other in trait-values. Disparity analysis suggested accelerated evolution (diversification in trait values above Brownian Motion expectations) in cell-size. We also found a significant phylogenetic regression between cell-size and fermentation versatility (R2 = 0.10), which suggests correlated evolution between both traits. Overall, our results do not support the early burst prediction both in species and traits, but suggest a number of interesting evolutionary patterns, that warrant further exploration. For instance, we show that the Whole Genomic Duplication that affected a whole clade of yeasts, does not seems to have a statistically detectable phenotypic effect at our level of analysis. In this regard, further studies of fermentation under common-garden conditions combined with comparative analyses are warranted.当新的生态机遇来源出现时，生理创新可触发适应性辐射（adaptive radiation）。这或许正是酵母菌（Saccharomycotina）的演化场景：其一项演化创新体现为利用果实中简单糖类的能力，即发酵（fermentation）。在适应性辐射过程中，物种多样化与形态演化被认为会在早期多样化爆发后趋于放缓。本研究首次针对酵母菌开展比较系统发育分析（comparative phylogenetic analysis），检验了物种多样化层面的"早期爆发"预测，同时也检验了推测具有生态相关性的性状（细胞大小与发酵多功能性）的相关预测。研究发现，在我们考量的约1.5亿年时间范围内，物种形成速率保持恒定。两种性状的系统发育信号（phylogenetic signal）均显著（但细胞大小的信号强度更低），表明演化支系间的性状值具有相似性。差异分析（disparity analysis）结果显示，细胞大小的演化速率存在加速现象，即其性状值的多样化程度高于布朗运动（Brownian Motion）的预期水平。本研究还发现，细胞大小与发酵多功能性之间存在显著的系统发育回归关系，决定系数R²=0.10，表明两种性状存在协同演化。总体而言，我们的研究结果既不支持物种多样化层面的早期爆发预测，也不支持性状演化层面的该预测，但揭示了若干值得进一步探究的有趣演化模式。例如，我们发现，影响整个酵母菌演化支的全基因组复制（Whole Genomic Duplication）事件，在本研究的分析尺度下未表现出可被统计检测到的表型效应。据此，未来有必要结合比较分析，开展同质园培养条件下的发酵相关研究。