氣候變化影響植物和動(dòng)物生命中定期發(fā)生的事件,，如發(fā)芽,、遷徙和冬眠以及種群動(dòng)態(tài)和形態(tài)變化。同時(shí)對(duì)所有這些相互作用的因素進(jìn)行監(jiān)測(cè)是困難的,，但對(duì)一種冬眠型哺乳動(dòng)物（美國(guó)科羅拉多州Upper East River Valley一個(gè)亞高山環(huán)境中的一種黃腹土撥鼠種群）所做的一項(xiàng)長(zhǎng)期生命史研究,，提供了適合于完成這項(xiàng)任務(wù)的數(shù)據(jù)。1976–2008年間的氣候變化使這些土撥鼠過早從冬眠中蘇醒過來,，延長(zhǎng)了它們的生長(zhǎng)季,，所以它們現(xiàn)在要比其開始冬眠時(shí)重一些。
與此同時(shí),，體型較大個(gè)體的適應(yīng)性也增加了,，導(dǎo)致種群規(guī)模迅速增大。正如Marcel Visser在配發(fā)的News & Views文章中所解釋的那樣，氣候變化生態(tài)學(xué)中的主要挑戰(zhàn)是預(yù)測(cè)未來氣候變化對(duì)于種群的影響,。
關(guān)于土撥鼠的這項(xiàng)研究工作提供了實(shí)現(xiàn)這一目的所需的數(shù)據(jù),。本期Nature封面所示為冬天在落基山脈拍攝的黃腹土撥鼠照片。(生物谷Bioon.com)
生物谷推薦原文出處：
Nature doi:10.1038/nature09210
Coupled dynamics of body mass and population growth in response to environmental change
Arpat Ozgul,Dylan Z. Childs,Madan K. Oli,Kenneth B. Armitage,Daniel T. Blumstein,Lucretia E. Olson,Shripad Tuljapurkar& Tim Coulson
Environmental change has altered the phenology, morphological traits and population dynamics of many species1, 2. However, the links underlying these joint responses remain largely unknown owing to a paucity of long-term data and the lack of an appropriate analytical framework3. Here we investigate the link between phenotypic and demographic responses to environmental change using a new methodology and a long-term (1976–2008) data set from a hibernating mammal (the yellow-bellied marmot) inhabiting a dynamic subalpine habitat. We demonstrate how earlier emergence from hibernation and earlier weaning of young has led to a longer growing season and larger body masses before hibernation. The resulting shift in both the phenotype and the relationship between phenotype and fitness components led to a decline in adult mortality, which in turn triggered an abrupt increase in population size in recent years. Direct and trait-mediated effects of environmental change made comparable contributions to the observed marked increase in population growth. Our results help explain how a shift in phenology can cause simultaneous phenotypic and demographic changes, and highlight the need for a theory integrating ecological and evolutionary dynamics in stochastic environments4, 5.
