Ghirlanda Stefano, Frasnelli Elisa, Vallortigara Giorgio
Department of Psychology, University of Bologna, Bologna, Italy.
Philos Trans R Soc Lond B Biol Sci. 2009 Apr 12;364(1519):861-6. doi: 10.1098/rstb.2008.0227.
Recent studies have revealed a variety of left-right asymmetries among vertebrates and invertebrates. In many species, left- and right-lateralized individuals coexist, but in unequal numbers ('population-level' lateralization). It has been argued that brain lateralization increases individual efficiency (e.g. avoiding unnecessary duplication of neural circuitry and reducing interference between functions), thus counteracting the ecological disadvantages of lateral biases in behaviour (making individual behaviour more predictable to other organisms). However, individual efficiency does not require a definite proportion of left- and right-lateralized individuals. Thus, such arguments do not explain population-level lateralization. We have previously shown that, in the context of prey-predator interactions, population-level lateralization can arise as an evolutionarily stable strategy when individually asymmetrical organisms must coordinate their behaviour with that of other asymmetrical organisms. Here, we extend our model showing that populations consisting of left- and right-lateralized individuals in unequal numbers can be evolutionarily stable, based solely on strategic factors arising from the balance between antagonistic (competitive) and synergistic (cooperative) interactions.
最近的研究揭示了脊椎动物和无脊椎动物之间存在多种左右不对称现象。在许多物种中，左右侧化的个体共存，但数量不等（“种群水平”的侧化）。有人认为，大脑侧化提高了个体效率（例如避免神经回路的不必要重复以及减少功能之间的干扰），从而抵消了行为中侧化偏差的生态劣势（使个体行为对其他生物更具可预测性）。然而，个体效率并不要求左右侧化个体有一定比例。因此，此类观点无法解释种群水平的侧化现象。我们之前已经表明，在捕食者 - 猎物相互作用的背景下，当个体不对称的生物体必须与其他不对称生物体协调其行为时，种群水平的侧化可以作为一种进化稳定策略出现。在此，我们扩展我们的模型，表明仅基于对抗（竞争）和协同（合作）相互作用之间平衡所产生的战略因素，由数量不等的左右侧化个体组成的种群可以是进化稳定的。
