Wiley RH, Steadman L, Chadwick L, Wollerman L
Department of Biology, University of North Carolina, Chapel Hill
Anim Behav. 1999 Feb;57(2):453-463. doi: 10.1006/anbe.1998.0991.
Social inertia is a term for the stability of dominance relationships despite changes in the intrinsic dominating abilities of opponents. In a standard test for social inertia, low-ranking birds in an established hierarchy receive implants with testosterone (treated) and high-ranking birds receive empty implants (untreated). Social inertia occurs when the treated birds remain subordinate to untreated opponents in these groups, despite evidence that similarly treated birds dominate untreated strangers. In previous demonstrations of social inertia, however, treated and untreated birds were returned to their original aviaries and tested with familiar opponents, and thus the effects of familiarity with the location and those of familiarity with opponents were not separated. To address this issue, we investigated social inertia in 16 groups of white-throated sparrows Zonotrichia albicollis. When low-ranking treated birds were placed in new aviaries with familiar high-ranking, untreated opponents (treatment S, same opponents), dominance relationships showed social inertia. When such birds were placed in new aviaries with unfamiliar opponents (treatment N, new opponents), testosterone influenced dominance. When groups of high-ranking, untreated birds acquainted with each other were placed with unfamiliar treated opponents (treatment G, grouped dominants), 'coat-tail' effects (dominance by association with high-ranking individuals) sometimes outweighed the effects of testosterone. Social inertia in this species is thus a result of familiarity with opponents, rather than familiarity with locations of encounters. Measurements of aggressive tendencies confirmed a previous report that social inertia suppresses activation of aggression by testosterone. White-throated sparrows can thus recognize their opponents, and this ability affects the expression of both dominance and aggression. Copyright 1999 The Association for the Study of Animal Behaviour.
社会惰性是指尽管对手的内在主导能力发生了变化，但主导关系仍保持稳定的一种现象。在一项社会惰性的标准测试中，既定等级制度中地位较低的鸟类接受睾酮植入（处理组），而地位较高的鸟类接受空植入物（未处理组）。当处理组的鸟类在这些群体中仍然服从于未处理的对手时，就会出现社会惰性，尽管有证据表明，接受类似处理的鸟类会主导未处理的陌生鸟类。然而，在先前社会惰性的演示中，处理组和未处理组的鸟类被放回它们原来的鸟舍，并与熟悉的对手进行测试，因此对地点的熟悉程度和对对手的熟悉程度的影响没有区分开来。为了解决这个问题，我们对白喉带鹀（Zonotrichia albicollis）的16个群体进行了社会惰性调查。当地位较低的处理组鸟类被放置在新的鸟舍中，与熟悉的地位较高的未处理对手在一起时（处理方式S，相同对手），主导关系表现出社会惰性。当这些鸟类被放置在新的鸟舍中，与不熟悉的对手在一起时（处理方式N，新对手），睾酮会影响主导地位。当相互熟悉的地位较高的未处理组鸟类与不熟悉的处理组对手放在一起时（处理方式G，聚集的优势个体），“搭便车”效应（通过与地位较高的个体关联而获得主导地位）有时会超过睾酮的影响。因此，该物种的社会惰性是对对手熟悉程度的结果，而不是对相遇地点熟悉程度的结果。攻击倾向的测量证实了之前的一份报告，即社会惰性会抑制睾酮对攻击行为的激活。白喉带鹀因此能够识别它们的对手，这种能力会影响主导地位和攻击行为的表现。版权所有1999年动物行为研究协会。
