Riley Julia L, Noble Daniel W A, Byrne Richard W, Whiting Martin J
Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia.
School of Biological, Earth, and Environmental Sciences, University of New South Wales, Kensington, NSW, Australia.
Anim Cogn. 2017 May;20(3):449-458. doi: 10.1007/s10071-016-1068-0. Epub 2016 Dec 26.
Early developmental environment can have profound effects on individual physiology, behaviour, and learning. In birds and mammals, social isolation during development is known to negatively affect learning ability; yet in other taxa, like reptiles, the effect of social isolation during development on learning ability is unknown. We investigated how social environment affects learning ability in the family-living tree skink (Egernia striolata). We hypothesized that early social environment shapes cognitive development in skinks and predicted that skinks raised in social isolation would have reduced learning ability compared to skinks raised socially. Offspring were separated at birth into two rearing treatments: (1) raised alone or (2) in a pair. After 1 year, we quantified spatial learning ability of skinks in these rearing treatments (N = 14 solitary, 14 social). We found no effect of rearing treatment on learning ability. The number of skinks to successfully learn the task, the number of trials taken to learn the task, the latency to perform the task, and the number of errors in each trial did not differ between isolated and socially reared skinks. Our results were unexpected, yet the facultative nature of this species' social system may result in a reduced effect of social isolation on behaviour when compared to species with obligate sociality. Overall, our findings do not provide evidence that social environment affects development of spatial learning ability in this family-living lizard.
早期发育环境会对个体的生理、行为和学习产生深远影响。在鸟类和哺乳动物中，发育期间的社会隔离已知会对学习能力产生负面影响；然而在其他类群中，比如爬行动物，发育期间的社会隔离对学习能力的影响尚不清楚。我们研究了社会环境如何影响群居的细鳞树蜥（Egernia striolata）的学习能力。我们假设早期社会环境会塑造树蜥的认知发展，并预测与群居饲养的树蜥相比，隔离饲养的树蜥学习能力会降低。幼崽在出生时被分为两种饲养处理方式：（1）单独饲养或（2）成对饲养。1年后，我们对处于这些饲养处理方式下的树蜥（单独饲养的14只，群居饲养的14只）的空间学习能力进行了量化。我们发现饲养处理方式对学习能力没有影响。成功学会任务的树蜥数量、学会任务所需的试验次数、执行任务的潜伏期以及每次试验中的错误数量，在隔离饲养和群居饲养的树蜥之间没有差异。我们的结果出乎意料，然而与具有 obligate sociality 的物种相比，该物种社会系统的兼性本质可能会导致社会隔离对行为的影响减弱。总体而言，我们的研究结果并未提供证据表明社会环境会影响这种群居蜥蜴的空间学习能力的发展。
