生物谷報道：人們常說人多力量大，但是棘魚似乎也明白這個道理。多國科學家組成的研究小組在5月12日的《國家科學院院刊》發(fā)表論文,，表明棘魚在游動時會自覺聚成一群，絕不單獨行動,。
當科學家讓一條假棘魚向著一條食肉魚游動時,，整個魚群并不會跟隨前者，除非大多數(shù)的魚都朝著這一方向游動,。這是一個聰明的策略,，因為由大多數(shù)個體作出的決定很可能比一條魚的決定更為安全。盡管蜜蜂和其他昆蟲也會以這樣的方式作出決定,，但之前尚未在脊椎動物中發(fā)現(xiàn)這種行為,。（生物谷www.bioon.com）
生物谷推薦原始出處：
PNAS，doi：10.1073/pnas.0710344105，Ashley J. W. Ward,，Jens Krause
Quorum decision-making facilitates information transfer in fish shoals
Ashley J. W. Ward*,, David J. T. Sumpter, Iain D. Couzin, Paul J. B. Hart¶, and Jens Krause||
*Centre for Mathematical Biology, School of Biological Sciences, University of Sydney, Sydney, New South Wales 2006, Australia; Mathematics Department, Uppsala University, 751 06 Uppsala, Sweden; Department of Ecology and Evolutionary Ecology, Princeton University, Princeton, NJ 08544; ¶Department of Biology, University of Leicester, Leicester LE1 7RH, United Kingdom; and ||Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom
Edited by Simon A. Levin, Princeton University, Princeton, NJ, and approved March 21, 2008 (received for review October 31, 2007)
Despite the growing interest in collective phenomena such as "swarm intelligence" and "wisdom of the crowds," little is known about the mechanisms underlying decision-making in vertebrate animal groups. How do animals use the behavior of others to make more accurate decisions, especially when it is not possible to identify which individuals possess pertinent information? One plausible answer is that individuals respond only when they see a threshold number of individuals perform a particular behavior. Here, we investigate the role of such "quorum responses" in the movement decisions of fish (three-spine stickleback, Gasterosteus aculeatus). We show that a quorum response to conspecifics can explain how sticklebacks make collective movement decisions, both in the absence and presence of a potential predation risk. Importantly our experimental work shows that a quorum response can reduce the likelihood of amplification of nonadaptive following behavior. Whereas the traveling direction of solitary fish was strongly influenced by a single replica conspecific, the replica was largely ignored by larger groups of four or eight sticklebacks under risk, and the addition of a second replica was required to exert influence on the movement decisions of such groups. Model simulations further predict that quorum responses by fish improve the accuracy and speed of their decision-making over that of independent decision-makers or those using a weak linear response. This study shows that effective and accurate information transfer in groups may be gained only through nonlinear responses of group members to each other, thus highlighting the importance of quorum decision-making.
