Data from: Ecological and evolutionary determinants for the adaptive radiation of the Madagascan vangas

Adaptive radiation is the rapid diversification of a single lineage into many species that inhabit a variety of environments or use a variety of resources and differ in traits required to exploit these. Why some lineages undergo adaptive radiation is not well-understood, but filling unoccupied ecological space appears to be a common feature. We construct a complete, dated, species-level phylogeny of the endemic Vangidae of Madagascar. This passerine bird radiation represents a classic, but poorly known, avian adaptive radiation. Our results reveal an initial rapid increase in evolutionary lineages and diversification in morphospace after colonizing Madagascar in the late Oligocene some 25 Mya. A subsequent key innovation involving unique bill morphology was associated with a second increase in diversification rates about 10 Mya. The volume of morphospace occupied by contemporary Madagascan vangas is in many aspects as large (shape variation)—or even larger (size variation)—as that of other better-known avian adaptive radiations, including the much younger Galapagos Darwin's finches and Hawaiian honeycreepers. Morphological space bears a close relationship to diet, substrate use, and foraging movements, and thus our results demonstrate the great extent of the evolutionary diversification of the Madagascan vangas.

适应辐射（Adaptive radiation）指单一演化支快速分化为多个物种，这些物种栖息于多样生境、利用多种资源，并具备适配此类资源开发的差异化性状。为何部分演化支会发生适应辐射仍未得到充分阐释，但占据未被利用的生态空间似乎是其普遍特征。我们构建了马达加斯加特有钩嘴鵙科（Vangidae）的完整、定年的物种水平系统发育树。该雀形目鸟类辐射演化事件属于经典却鲜为人知的鸟类适应辐射案例。研究结果显示，该类群于约2500万年前的晚渐新世（late Oligocene）拓殖马达加斯加后，演化支数量与形态空间分异率先出现快速增长。此后，一项涉及独特喙部形态的关键创新，与约1000万年前的第二次分异速率提升存在关联。现代马达加斯加钩嘴鵙所占据的形态空间体积，在诸多维度上与其他知名鸟类适应辐射类群相当（形状变异维度）——甚至在体型变异维度上更具优势，包括年代更晚近的加拉帕戈斯达尔文雀与夏威夷旋蜜雀。形态空间与食性、基质利用及觅食行为密切相关，因此本研究结果证实了马达加斯加钩嘴鵙的演化分异程度之高。