School of Biological Sciences, University of Sydney, Sydney, New South Wales, Australia.
PLoS One. 2011 Apr 6;6(4):e18277. doi: 10.1371/journal.pone.0018277.
Brain size relative to body size varies considerably among animals, but the ecological consequences of that variation remain poorly understood. Plausibly, larger brains confer increased behavioural flexibility, and an ability to respond to novel challenges. In keeping with that hypothesis, successful invasive species of birds and mammals that flourish after translocation to a new area tend to have larger brains than do unsuccessful invaders. We found the same pattern in ectothermic terrestrial vertebrates. Brain size relative to body size was larger in species of amphibians and reptiles reported to be successful invaders, compared to species that failed to thrive after translocation to new sites. This pattern was found in six of seven global biogeographic realms; the exception (where relatively larger brains did not facilitate invasion success) was Australasia. Establishment success was also higher in amphibian and reptile families with larger relative brain sizes. Future work could usefully explore whether invasion success is differentially associated with enlargement of specific parts of the brain (as predicted by the functional role of the forebrain in promoting behavioural flexibility), or with a general size increase (suggesting that invasion success is facilitated by enhanced perceptual and motor skills, as well as cognitive ability).
大脑相对于身体的大小在动物中差异很大，但这种变化的生态后果仍知之甚少。合理的假设是，更大的大脑赋予了动物更高的行为灵活性和应对新挑战的能力。根据这一假设，在被转移到新的地区后成功繁殖的鸟类和哺乳动物等入侵物种，其大脑往往比不成功的入侵物种更大。我们在变温陆生脊椎动物中也发现了同样的模式。与那些在被转移到新地点后无法茁壮成长的物种相比，报道中成功入侵的两栖类和爬行类物种的大脑大小与身体大小的比值更大。这一模式在七个全球生物地理区域中的六个区域中都存在；唯一的例外是（相对较大的大脑并没有促进入侵的成功）是澳大拉西亚地区。具有较大相对脑容量的两栖类和爬行类家族的建立成功率也更高。未来的工作可以探讨入侵的成功是否与大脑特定部位的扩大（如前脑在促进行为灵活性方面的功能作用所预测的那样）或整体大小的增加（表明入侵的成功是通过增强感知和运动技能以及认知能力来实现的）相关。
