Molnár Orsolya, Bajer Katalin, Mészáros Boglárka, Török János, Herczeg Gábor
Department of Biological Sciences, Life Sciences Center, Dartmouth College, 78 College Street, Hanover, NH 03755, USA.
Naturwissenschaften. 2013 Jun;100(6):551-8. doi: 10.1007/s00114-013-1051-4. Epub 2013 May 5.
During female mate choice, conspicuous male sexual signals are used to infer male quality and choose the best sire for the offspring. The theory of parasite-mediated sexual selection (Hamilton-Zuk hypothesis) presumes that parasite infection can influence the elaboration of sexual signals: resistant individuals can invest more energy into signal expression and thus advertise their individual quality through signal intensity. By preferring these males, females can provide resistance genes for their offspring. Previous research showed that nuptial throat colour of male European green lizard, Lacerta viridis, plays a role in both inter- and intrasexual selections as a condition-dependent multiple signalling system. The aim of this study was to test the predictions of the Hamilton-Zuk hypothesis on male European green lizards. By blood sampling 30 adult males during the reproductive season, we found members of the Haemogregarinidae family in all but one individual (prevalence = 96%). The infection intensity showed strong negative correlation with the throat and belly colour brightness in line with the predictions of the Hamilton-Zuk hypothesis. In addition, we found other correlations between infection intensity and other fitness-related traits, suggesting that parasite load has a remarkable effect on individual fitness. This study shows that throat patch colour of the European green lizards not only is a multiple signalling system but also possibly acts as an honest sexual signal of health state in accordance with the Hamilton-Zuk hypothesis.
在雌性择偶过程中，雄性明显的性信号被用于推断雄性质量，并为后代选择最佳父本。寄生虫介导的性选择理论（汉密尔顿-祖克假说）假定，寄生虫感染会影响性信号的表现：具有抗性的个体能够将更多能量投入到信号表达中，从而通过信号强度来展示其个体质量。通过选择这些雄性，雌性可以为其后代提供抗性基因。先前的研究表明，雄性欧洲绿蜥蜴（绿蜥蜴）的婚羽喉部颜色，作为一种依赖条件的多重信号系统，在种间和种内选择中都发挥着作用。本研究的目的是检验汉密尔顿-祖克假说对雄性欧洲绿蜥蜴的预测。在繁殖季节对30只成年雄性进行采血，我们发现除一只个体外，所有个体（患病率 = 96%）均感染了血簇虫科的成员。感染强度与喉部和腹部颜色亮度呈强烈负相关，这与汉密尔顿-祖克假说的预测一致。此外，我们还发现感染强度与其他与适应性相关的性状之间存在其他相关性，表明寄生虫负荷对个体适应性有显著影响。这项研究表明，欧洲绿蜥蜴的喉部斑块颜色不仅是一种多重信号系统，而且根据汉密尔顿-祖克假说，还可能作为健康状况的诚实性信号。
