Data from: Isolation rearing does not constrain social plasticity in a family-living lizard

An animal’s social environment can be both dynamic and complex. Thus, social species often garner fitness benefits through being plastic in their social behavior. Yet, social plasticity can be constrained by an individual’s experience. We examined the influence of early social environment on social behavior in the tree skink (Egernia striolata), a family-living lizard. In the first phase of this study, we reared juveniles in two different social environments for 1.5 years: either in isolation or in unrelated pairs. We quantified each lizard’s sociability at four-month intervals using a standardized laboratory assay, and found that isolated lizards were more sociable, spending the assay closer to an adult female, than socially-reared lizards. In the second phase of this study (at the end of 1.5 years), we released all lizards into a semi-natural environment, observed their associations, and used social network analysis to quantify social behavior. During the initial six weeks post-release, we detected no differences in social behavior between rearing treatments. However, during the following six months differences emerged. Isolated lizards were more homogeneous in the strength of their associations than socially-reared lizards. Also, at first, isolated lizards associated more strongly than socially-reared lizards. Over time, isolated lizard associations became weaker and involved fewer lizards. In contrast, the level and number of associations of socially-reared lizards were stable over time. Our findings suggest that early experience influences tree skink social behavior but does not constrain social plasticity: isolation rearing did not limit their ability to respond to a novel social environment.动物所处的社会环境兼具动态性与复杂性。因此，群居物种往往可通过调控自身社会行为的可塑性（social plasticity）来获取适合度收益。然而，个体的过往经历会对社会可塑性造成约束。 本研究以家族群居的木纹石龙子（Egernia striolata）为研究对象，探究早期社会环境对其社会行为的影响。研究第一阶段中，我们将幼体置于两种不同的社会环境中饲养1.5年：分别为单独饲养，以及与非亲缘个体成对饲养。我们每四个月通过标准化实验室测试，量化每只石龙子的社交性，结果发现，相较于群居饲养的个体，单独饲养的石龙子表现出更高的社交性——在测试过程中它们会更贴近成年雌性个体。 研究第二阶段（即饲养1.5年结束后），我们将所有石龙子放归至半自然环境中，观察它们的社交关联，并通过社交网络分析（social network analysis）量化其社会行为。在放归后的初始六周内，我们未检测到不同饲养处理组间的社会行为存在显著差异。但在后续的六个月中，组间差异逐渐显现：单独饲养组的石龙子，其社交关联强度的均一性要高于群居饲养组个体；此外，在阶段初期，单独饲养组个体的社交关联强度要高于群居饲养组。随着时间推移，单独饲养组个体的社交关联强度逐渐减弱，且参与社交关联的个体数量也有所减少。与之形成对比的是，群居饲养组个体的社交关联强度与关联数量均随时间保持稳定。 本研究结果表明，早期经历会对木纹石龙子的社会行为产生影响，但并未对其社会可塑性造成约束——单独饲养并未限制它们对全新社会环境的适应能力。