了解物種之間的互動(dòng)怎樣幫助維護(hù)物種多樣性，是生態(tài)學(xué)中的一個(gè)基礎(chǔ)性問題,。Peter Chesson 和 Jessica Kuang提出的新的理論結(jié)果,，突出顯示了捕食與競(jìng)爭(zhēng)在決定共存中所扮演的相互獨(dú)立的角色。他們發(fā)現(xiàn),，每個(gè)機(jī)制都能通過與特定物種的多樣關(guān)系來(lái)促進(jìn)多樣性,，或通過讓某種物種彼此之間進(jìn)行競(jìng)爭(zhēng)的狹隘關(guān)系來(lái)限制多樣性。每個(gè)機(jī)制也都能減小另一個(gè)機(jī)制的影響,，或與另一個(gè)機(jī)制協(xié)同作用來(lái)促進(jìn)多樣性,，由具體情況來(lái)決定。（生物谷Bioon.com）
生物谷推薦原始出處：
Nature 456, 235-238 (13 November 2008) | doi:10.1038/nature07248
The interaction between predation and competition
Peter Chesson & Jessica J. Kuang
Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, Arizona 85721, USA
Competition and predation are the most heavily investigated species interactions in ecology, dominating studies of species diversity maintenance. However, these two interactions are most commonly viewed highly asymmetrically. Competition for resources is seen as the primary interaction limiting diversity, with predation modifying what competition does1, although theoretical models have long supported diverse views1, 2, 3, 4, 5. Here we show, using a comprehensive three-trophic-level model, that competition and predation should be viewed symmetrically: these two interactions are equally able to either limit or promote diversity. Diversity maintenance requires within-species density feedback loops to be stronger than between-species feedback loops. We quantify the contributions of predation and competition to these loops in a simple, interpretable form, showing their equivalent potential to strengthen or weaken diversity maintenance. Moreover, we show that competition and predation can undermine each other, with the tendency of the stronger interaction to promote or limit diversity prevailing. The past failure to appreciate the symmetrical effects and interactions of competition and predation has unduly restricted diversity maintenance studies. A multitrophic perspective should be adopted to examine a greater variety of possible effects of predation than generally considered in the past. Conservation and management strategies need to be much more concerned with the implications of changes in the strengths of trophic interactions.
