Department of Biology, University of Rochester, Rochester, NY 14627, USA.
Proc Biol Sci. 2013 Mar 27;280(1759):20122703. doi: 10.1098/rspb.2012.2703. Print 2013 May 22.
Many short-lived desert organisms remain in diapause during drought. Theoretically, the cues desert species use to continue diapause through drought should differ depending on the availability of critical resources, but the unpredictability and infrequent occurrence of climate extremes and reduced insect activity during such events make empirical tests of this prediction difficult. An intensive study of a diverse bee-plant community through a drought event found that bee specialists of a drought-sensitive host plant were absent in the drought year in contrast to generalist bees and to specialist bees of a drought-insensitive host plant. Different responses of bee species to drought indicate that the diapause cues used by bee species allow them to reliably predict host availability. Species composition of the bee community in drought shifted towards mostly generalist species. However, we predict that more frequent and extended drought, predicted by climate change models for southwest North America, will result in bee communities that are species-poor and dominated by specialist species, as found today in the most arid desert region of North America.
许多短命的沙漠生物在干旱期间处于休眠状态。理论上，沙漠物种用来通过干旱继续休眠的线索应该根据关键资源的可用性而有所不同，但气候极端事件的不可预测性和罕见性以及此类事件期间昆虫活动的减少使得对这一预测的实证检验变得困难。通过一次干旱事件对一个多样化的蜜蜂-植物群落进行的深入研究发现，与普通蜜蜂和对干旱不敏感的宿主植物的专门蜜蜂相比，干旱敏感宿主植物的专门蜜蜂在干旱年份中不存在。不同的蜜蜂物种对干旱的反应表明，蜜蜂物种使用的休眠线索使它们能够可靠地预测宿主的可用性。干旱时蜜蜂群落的物种组成向主要是普通物种转移。然而，我们预测，气候变化模型预测的北美西南部更频繁和更长时间的干旱将导致蜜蜂群落物种贫乏，以专门物种为主，就像今天在北美最干旱的沙漠地区一样。
