中科院昆明動物研究所的王瑞武,、張亞平院士等合作在互利合作行為演化及系統(tǒng)維持機制（協(xié)同進化）研究取得重要進展，相關成果文章Interference Competition and High Temperatures Reduce the Virulence of Fig Wasps and Stabilize a Fig-Wasp Mutualism發(fā)表在11月12的PLoS ONE上,。
互利合作行為不僅存在于種內系統(tǒng)的各個群體內(Group),，也廣泛存在于物種之間，而越來越多的發(fā)現(xiàn)顯示幾乎所有的物種都至少與一個其它物種存在互利的共棲行為（Bronstein 2001 in Ecology Letters）,。
從十九世紀二十年代開始,，榕樹與其特有的傳粉昆蟲系統(tǒng)一直是研究物種之間是如何形成穩(wěn)定的合作關系的模式系統(tǒng)之一。在探討物種間互利合作行為的過程中,，一個基本的理論問題一直未曾得到解決：互利共棲的物種之間存在公共資源,，而任何一個物種的個體對公共資源的過度利用都會導致合作關系的解體，這就是著名的“公共地的悲劇”（該悖論由Hardin于1968年在Science提出）,。
經(jīng)典理論認為合作雙方利用的空間資源存在分化,，因而合作一方不能利用另外一方的資源。
然而,，王瑞武等的實驗表明：資源的空間分化理論可能是不可信的（對文獻提到多個空間分化假說逐一實驗驗證和分析發(fā)現(xiàn)都是不可信的）,，合作關系將會隨著公共資源的減少而轉化為沖突關系，公共資源豐富時,，雙方表現(xiàn)為合作關系,，而在公共資源緊張時表現(xiàn)沖突或競爭關系（Wang et al. 2008, in Journal Animal Ecology）。
王瑞武等的實驗發(fā)現(xiàn)：傳粉小蜂之間存在干擾性競爭,，這種干擾性競爭將導致傳粉小蜂對公共資源利用效率的降低,，因而公共資源的利用由于傳粉小蜂之間的干擾性競爭而不能達到最大化，合作雙方的公共資源利用很少達到緊張狀態(tài),，物種之間因而能夠維持比較穩(wěn)定的合作關系,。
這是國內首次用實驗證據(jù)論證了空間分化在互利合作系統(tǒng)中并不能維持合作關系的穩(wěn)定，并首次提出了非對稱性的干擾可能是維持互利合作系統(tǒng)穩(wěn)定的關鍵機制。（生物谷Bioon.com）
生物谷推薦原始出處：
PLoS ONE 4(11): e7802. doi:10.1371/journal.pone.0007802
Interference Competition and High Temperatures Reduce the Virulence of Fig Wasps and Stabilize a Fig-Wasp Mutualism
Rui-Wu Wang1#, Jo Ridley2#, Bao-Fa Sun1,3, Qi Zheng1,4, Derek W. Dunn2,5, James Cook5, Lei Shi6, Ya-Ping Zhang1, Douglas W. Yu1,2*
1 Ecology, Conservation, and Environment Center (ECEC), State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China, 2 Centre for Ecology, Evolution and Conservation (CEEC) and School of Biological Sciences, University of East Anglia, Norwich, Norfolk, United Kingdom, 3 Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing, China, 4 School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China, 5 School of Biological Sciences, University of Reading, Reading, Berks, United Kingdom, 6 Statistics and Mathematics College, Yunnan University of Finance and Economics, Kunming, Yunnan, China
Fig trees are pollinated by fig wasps, which also oviposit in female flowers. The wasp larvae gall and eat developing seeds. Although fig trees benefit from allowing wasps to oviposit, because the wasp offspring disperse pollen, figs must prevent wasps from ovipositing in all flowers, or seed production would cease, and the mutualism would go extinct. In Ficus racemosa, we find that syconia (‘figs’) that have few foundresses (ovipositing wasps) are underexploited in the summer (few seeds, few galls, many empty ovules) and are overexploited in the winter (few seeds, many galls, few empty ovules). Conversely, syconia with many foundresses produce intermediate numbers of galls and seeds, regardless of season. We use experiments to explain these patterns, and thus, to explain how this mutualism is maintained. In the hot summer, wasps suffer short lifespans and therefore fail to oviposit in many flowers. In contrast, cooler temperatures in the winter permit longer wasp lifespans, which in turn allows most flowers to be exploited by the wasps. However, even in winter, only in syconia that happen to have few foundresses are most flowers turned into galls. In syconia with higher numbers of foundresses, interference competition reduces foundress lifespans, which reduces the proportion of flowers that are galled. We further show that syconia encourage the entry of multiple foundresses by delaying ostiole closure. Taken together, these factors allow fig trees to reduce galling in the wasp-benign winter and boost galling (and pollination) in the wasp-stressing summer. Interference competition has been shown to reduce virulence in pathogenic bacteria. Our results show that interference also maintains cooperation in a classic, cooperative symbiosis, thus linking theories of virulence and mutualism. More generally, our results reveal how frequency-dependent population regulation can occur in the fig-wasp mutualism, and how a host species can ‘set the rules of the game’ to ensure mutualistic behavior in its symbionts.
