Global elevational diversity and diversification of birds
Global elevational diversity and diversification of birds
复制标题
DOI：
10.1038/nature25794
复制
发表时间：
2018-03-08
期刊：
影响因子：
64.8
通讯作者：
Jetz, Walter
中科院分区：
文献类型：
--
作者：
Quintero, Ignacio;Jetz, Walter
山脉拥有极高的生物多样性，但现在正受到快速环境变化的威胁。然而，尽管经过数十年的努力，数据和分析工具的可用性有限，阻碍了对海拔生物多样性梯度及其进化起源的可靠和真正的全球表征（1,2）。这妨碍了对山地群落聚集和维持过程的一般理解（2-4）。在这里，我们发现鸟类丰富度的全球中高海拔峰值是由广泛的物种驱动的，当我们使用亚采样程序确保物种在空间上的代表性并促进进化解释时，这种峰值就会消失。相反，经过范围大小校正的丰富度随着海拔的增加呈线性下降。我们发现，在所有山区，海拔越高的群落越不充分，多样性率越高，这就否定了近期多样性率较低是生物群多样性减少的一般原因的观点。在所有海拔高度，过去温度变化速率高的山区的物种组合表现出更快的多样化，突出了气候波动在推动山区生物多样性进化动态方面的重要性。虽然山区不同的地貌和气候属性是决定今天观察到的显著丰富度梯度的关键，但我们的研究结果强调了正在进行的、通常是最近的多样化过程在维持高海拔地区独特和高度适应的生物多样性方面的作用。
Mountain ranges harbour exceptionally high biodiversity, which is now under threat from rapid environmental change. However, despite decades of effort, the limited availability of data and analytical tools has prevented a robust and truly global characterization of elevational biodiversity gradients and their evolutionary origins(1,2). This has hampered a general understanding of the processes involved in the assembly and maintenance of montane communities(2-4). Here we show that a worldwide midelevation peak in bird richness is driven by wide-ranging species and disappears when we use a subsampling procedure that ensures even species representation in space and facilitates evolutionary interpretation. Instead, richness corrected for range size declines linearly with increasing elevation. We find that the more depauperate assemblages at higher elevations are characterized by higher rates of diversification across all mountain regions, rejecting the idea that lower recent diversification rates are the general cause of less diverse biota. Across all elevations, assemblages on mountains with high rates of past temperature change exhibit more rapid diversification, highlighting the importance of climatic fluctuations in driving the evolutionary dynamics of mountain biodiversity. While different geomorphological and climatic attributes of mountain regions have been pivotal in determining the remarkable richness gradients observed today, our results underscore the role of ongoing and often very recent diversification processes in maintaining the unique and highly adapted biodiversity of higher elevations.