Division of Ecology & Evolution, Research School of Biology, The Australian National University, Canberra, ACT, Australia.
Evolution. 2024 Oct 28;78(11):1854-1868. doi: 10.1093/evolut/qpae132.
Understanding how continental radiations are assembled across space and time is a major question in macroevolutionary biology. Here, we use a phylogenomic-scale phylogeny, a comprehensive morphological dataset, and environmental niche models to evaluate the relationship between trait and environment and assess the role of geography and niche conservatism in the continental radiation of Australian blindsnakes. The Australo-Papuan blindsnake genus, Anilios, comprises 47 described species of which 46 are endemic to and distributed across various biomes on continental Australia. Although we expected blindsnakes to be morphologically conserved, we found considerable interspecific variation in all morphological traits we measured. Absolute body length is negatively correlated with mean annual temperature, and body shape ratios are negatively correlated with soil compactness. We found that morphologically similar species are likely not a result of ecological convergence. Age-overlap correlation tests revealed niche similarity decreased with the relative age of speciation events. We also found low geographical overlap across the phylogeny, suggesting that speciation is largely allopatric with low rates of secondary range overlap. Our study offers insights into the eco-morphological evolution of blindsnakes and the potential for phylogenetic niche conservatism to influence continental scale radiations.
理解大陆辐射如何在空间和时间上组装是宏观进化生物学中的一个主要问题。在这里，我们使用系统发育尺度的系统发育树、全面的形态数据集和环境生态位模型来评估特征与环境之间的关系，并评估地理和生态位保守性在澳大利亚盲蛇大陆辐射中的作用。澳大拉西亚-巴布亚盲蛇属，Anilios，由 47 种已描述的物种组成，其中 46 种是澳大利亚大陆各种生物群落的特有种。尽管我们预计盲蛇在形态上是保守的，但我们发现我们测量的所有形态特征都存在相当大的种间变异。绝对体长与年平均温度呈负相关，身体形状比与土壤紧实度呈负相关。我们发现形态相似的物种可能不是生态趋同的结果。年龄重叠相关测试表明，随着物种形成事件的相对年龄的增加，生态位相似性降低。我们还发现系统发育中地理重叠程度低，这表明物种形成主要是异域的，二次分布范围重叠率低。我们的研究为盲蛇的生态形态进化提供了深入的了解，并为系统发育生态位保守性影响大陆尺度辐射提供了潜力。
