Mercer John M, Roth V Louise
Biology Department, Duke University, Durham, NC 27708-0338, USA.
Science. 2003 Mar 7;299(5612):1568-72. doi: 10.1126/science.1079705. Epub 2003 Feb 20.
By modifying habitats and creating bridges and barriers between landmasses, climate change and tectonic events are believed to have important consequences for diversification of terrestrial organisms. Such consequences should be most evident in phylogenetic histories of groups that are ancient, widespread, and diverse. The squirrel family (Sciuridae) is one of very few mammalian families endemic to Eurasia, Africa, and North and South America and is ideal for examining these issues. Through phylogenetic and molecular-clock analyses, we infer that arrival and diversification of squirrels in Africa, on Sunda Shelf islands, across Beringea, and across the Panamanian isthmus coincide in timing and location with multiple well-documented sea-level, tectonic, and paleontological events. These precise correspondences point to an important role for global change in the diversification of a major group of mammals.
气候变化和构造活动通过改变栖息地以及在陆地块体之间建立桥梁和屏障，被认为对陆地生物的多样化具有重要影响。这种影响在古老、分布广泛且种类繁多的类群的系统发育历史中应该最为明显。松鼠科是极少数在欧亚大陆、非洲以及南北美洲都有分布的哺乳动物科之一，是研究这些问题的理想对象。通过系统发育和分子钟分析，我们推断松鼠在非洲、巽他陆架岛屿、白令陆桥以及巴拿马地峡的到达和多样化，在时间和地点上与多个有充分记录的海平面、构造和古生物学事件相吻合。这些精确的对应关系表明全球变化在一个主要哺乳动物类群的多样化过程中发挥了重要作用。
