The phylogeny and biogeography of Hakea (Proteaceae) reveals the role of biome shifts in a continental plant radiation

The frequency of evolutionary biome shifts during diversification has important implications for our ability to explain geographic patterns of plant diversity. Recent studies present several examples of biome shifts, but whether frequencies of biome shifts closely reflect geographic proximity or environmental similarity of biomes remains poorly known. We explore this question by using phylogenomic methods to estimate the phylogeny of Hakea, a diverse Australian genus occupying a wide range of biomes. Model-based estimation of ancestral regions indicates that Hakea began diversifying in the Mediterranean biome of southern Australia in the Middle Eocene – Early Oligocene, and dispersed repeatedly into other biomes across the continent. We infer around 47 shifts between biomes. Frequencies of shifts between pairs of biomes are usually similar to those expected from their geographic connectedness or climatic similarity, but in some cases are substantially higher or lower than expected, perh...物种分化过程中演化生物群系(biome)转移的频率，对于我们解释植物多样性的地理分布格局具有重要意义。已有多项研究提供了生物群系转移的实例，但生物群系转移的频率是否紧密反映生物群系的地理邻近性或环境相似性，目前仍不甚明确。我们以占据多种不同生物群系的澳大利亚多样性属哈克木属（Hakea）为研究对象，通过系统发育基因组学(phylogenomic)方法估算其系统发育关系，以此探讨上述问题。基于模型的祖先分布区估算结果显示，哈克木属于中始新世-早渐新世时期在澳大利亚南部的地中海生物群区内开始分化，并多次扩散至澳洲大陆的其他生物群系中。我们推断生物群系间的转移事件约有47次。成对生物群系间的转移频率通常与基于二者地理连通性或气候相似性所预期的频率相近，但在部分情形下，其转移频率显著高于或低于预期，或许...