Kotrschal Alexander, Deacon Amy E, Magurran Anne E, Kolm Niclas
1Department of Ethology/Zoology, Stockholm University, Svante Arheniusväg 18B, 10691 Stockholm, Sweden.
2Department of Life Sciences, The University of the West Indies, St Augustine, Trinidad and Tobago.
Evol Ecol. 2017;31(5):619-633. doi: 10.1007/s10682-017-9901-8. Epub 2017 May 12.
There is remarkable diversity in brain anatomy among vertebrates and evidence is accumulating that predatory interactions are crucially important for this diversity. To test this hypothesis, we collected female guppies () from 16 wild populations and related their brain anatomy to several aspects of predation pressure in this ecosystem, such as the biomass of the four major predators of guppies (one prawn and three fish species), and predator diversity (number of predatory fish species in each site). We found that populations from localities with higher prawn biomass had relatively larger telencephalon size as well as larger brains. Optic tectum size was positively associated with one of the fish predator's biomass and with overall predator diversity. However, both olfactory bulb and hypothalamus size were negatively associated with the biomass of another of the fish predators. Hence, while fish predator occurrence is associated with variation in brain anatomy, prawn occurrence is associated with variation in brain size. Our results suggest that cognitive challenges posed by local differences in predator communities may lead to changes in prey brain anatomy in the wild.
脊椎动物的脑解剖结构存在显著差异，并且越来越多的证据表明，捕食相互作用对这种差异至关重要。为了验证这一假设，我们从16个野生种群中收集了雌性孔雀鱼，并将它们的脑解剖结构与该生态系统中捕食压力的几个方面联系起来，比如孔雀鱼的四种主要捕食者（一种对虾和三种鱼类）的生物量，以及捕食者多样性（每个地点捕食性鱼类的种类数量）。我们发现，来自对虾生物量较高地区的种群，其端脑相对较大，大脑也较大。视顶盖大小与其中一种捕食性鱼类的生物量以及总体捕食者多样性呈正相关。然而，嗅球和下丘脑的大小均与另一种捕食性鱼类的生物量呈负相关。因此，虽然捕食性鱼类的出现与脑解剖结构的变化有关，但对虾的出现与脑大小的变化有关。我们的结果表明，捕食者群落的局部差异所带来的认知挑战可能会导致野生猎物脑解剖结构的变化。
