Eiserhardt Wolf L, Borchsenius Finn, Plum Christoffer M, Ordonez Alejandro, Svenning Jens-Christian
Section for Ecoinformatics & Biodiversity, Department of Bioscience, Aarhus University, Ny Munkegade 114, DK-8000, Aarhus C, Denmark; Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3AE, UK.
Ecol Lett. 2015 Mar;18(3):263-72. doi: 10.1111/ele.12409. Epub 2015 Jan 20.
When taxa go extinct, unique evolutionary history is lost. If extinction is selective, and the intrinsic vulnerabilities of taxa show phylogenetic signal, more evolutionary history may be lost than expected under random extinction. Under what conditions this occurs is insufficiently known. We show that late Cenozoic climate change induced phylogenetically selective regional extinction of northern temperate trees because of phylogenetic signal in cold tolerance, leading to significantly and substantially larger than random losses of phylogenetic diversity (PD). The surviving floras in regions that experienced stronger extinction are phylogenetically more clustered, indicating that non-random losses of PD are of increasing concern with increasing extinction severity. Using simulations, we show that a simple threshold model of survival given a physiological trait with phylogenetic signal reproduces our findings. Our results send a strong warning that we may expect future assemblages to be phylogenetically and possibly functionally depauperate if anthropogenic climate change affects taxa similarly.
当分类群灭绝时，独特的进化史就会丧失。如果灭绝具有选择性，并且分类群的内在脆弱性显示出系统发育信号，那么可能会失去比随机灭绝预期更多的进化史。这种情况在何种条件下发生尚不清楚。我们表明，由于耐寒性的系统发育信号，晚新生代气候变化导致北半球温带树木发生系统发育选择性区域灭绝，导致系统发育多样性（PD）的丧失显著且大幅超过随机水平。经历更强灭绝的地区现存植物群在系统发育上更加聚集，这表明随着灭绝严重程度的增加，PD的非随机丧失越来越令人担忧。通过模拟，我们表明，一个给定具有系统发育信号的生理特征的简单生存阈值模型再现了我们的发现。我们的结果发出了一个强烈警告：如果人为气候变化对分类群产生类似影响，我们可能会预期未来的生物群落将在系统发育上以及可能在功能上变得贫瘠。
