Rödel Heiko G, von Holst Dietrich
Department of Animal Physiology, University of Bayreuth, D-95440 Bayreuth, Germany.
Physiol Behav. 2009 Jun 22;97(3-4):495-502. doi: 10.1016/j.physbeh.2009.04.005. Epub 2009 Apr 16.
The outcome of an intra-specific aggressive encounter between two competitors is frequently influenced by differences in individual characteristics. Apart from differences in adult body condition, aspects of the early juvenile development, which are commonly found to influence traits during later life, may be of particular importance. In an observational study on individually marked European rabbit males (Oryctolagus cuniculus L.) from a field enclosure, we investigated short-term and long-term consequences of different features of the early development on measures of competitive performance during later life. Males from smaller litters, which consequently had a higher nestling body mass, showed more escalated offensive behavior (chasing) against other juveniles during juvenile life. Furthermore, such males were more offensive and successful fighters in intra-sexual conflicts during their first breeding season. Interestingly, when comparing the effects of different measures of body mass during different life stages, the nestling mass was the best predictor for male competitive performance after maturity. The body mass measured during the late juvenile stage in autumn was also significantly, but more weakly correlated with the males' offensive behavior after maturity, whereas the adult body mass did not show significant effects. In conclusion our study points out, that parameters of the early development are involved in shaping the competitive performance during later life via other mechanisms than just by promoting a high adult body mass.
两个竞争者之间种内攻击性遭遇的结果常常受到个体特征差异的影响。除了成年个体身体状况的差异外，幼年期早期发育的一些方面通常被发现会影响后期生活中的性状，可能尤为重要。在一项对来自野外围栏中单独标记的欧洲雄兔（穴兔）的观察研究中，我们调查了早期发育的不同特征对后期生活中竞争表现指标的短期和长期影响。来自较小窝仔数的雄性，因此具有更高的雏鸟体重，在幼年期对其他幼兔表现出更激烈的攻击行为（追逐）。此外，这些雄性在第一个繁殖季节的同性冲突中更具攻击性且是更成功的战斗者。有趣的是，当比较不同生命阶段不同体重测量指标的影响时，雏鸟体重是成熟后雄性竞争表现的最佳预测指标。秋季幼年期后期测量的体重也与成熟后雄性的攻击行为显著相关，但相关性较弱，而成年体重则未显示出显著影响。总之，我们的研究指出，早期发育参数通过其他机制参与塑造后期生活中的竞争表现，而不仅仅是通过促进高成年体重。
