Mougi Akihiko, Nishimura Kinya
Graduate School of Fisheries Sciences, Hokkaido University, Hakodate 041-8611, Japan.
Proc Biol Sci. 2008 Nov 22;275(1651):2563-8. doi: 10.1098/rspb.2008.0889.
Paradoxically, enrichment can destabilize a predator-prey food web. While adaptive dynamics can greatly influence the stability of interaction systems, few theoretical studies have examined the effect of the adaptive dynamics of interaction-related traits on the possibility of resolution of the paradox of enrichment. We consider the evolution of attack and defence traits of a predator and two prey species in a one predator-two prey system in which the predator practises optimal diet use. The results showed that optimal foraging alone cannot eliminate a pattern of destabilization with enrichment, but trait evolution of the predator or prey can change the pattern to one of stabilization, implying a possible resolution of the paradox of enrichment. Furthermore, trait evolution in all species can broaden the parameter range of stabilization. Importantly, rapid evolution can stabilize this system, but weaken its stability in the face of enrichment.
矛盾的是，物种丰富化会破坏捕食者 - 猎物的食物网稳定性。虽然适应性动态可以极大地影响相互作用系统的稳定性，但很少有理论研究考察与相互作用相关性状的适应性动态对解决物种丰富化悖论可能性的影响。我们考虑了一个单捕食者 - 双猎物系统中捕食者以及两种猎物的攻击和防御性状的进化，在该系统中捕食者采用最优饮食策略。结果表明，仅最优觅食并不能消除物种丰富化导致的不稳定模式，但捕食者或猎物的性状进化可以将这种模式转变为稳定模式，这意味着物种丰富化悖论可能得到解决。此外，所有物种的性状进化可以拓宽稳定的参数范围。重要的是，快速进化可以使这个系统稳定，但在物种丰富化的情况下会削弱其稳定性。
