1 Centre for Evolutionary Biology, School of Biological Sciences, The University of Western Australia , Crawley, Western Australia 6009 , Australia.
2 Department of Ecology, Evolution and Behavior, and Minnesota Center for Philosophy of Science, University of Minnesota , Twin Cities, St Paul, MN 55108 , USA.
Proc Biol Sci. 2019 May 15;286(1902):20190677. doi: 10.1098/rspb.2019.0677.
While the reproductive benefits of sexual displays have been widely studied, we have relatively limited evidence of the fitness costs associated with most display traits. Insect cuticular hydrocarbon (CHC) profiles are sexually selected traits that also protect against desiccation. These two functions are thought to oppose each other, with investment in particular compounds believed to increase attractiveness at the expense of compounds that protect against water loss. We investigated this potential trade-off in a quantitative genetic framework using the Australian field cricket, Teleogryllus oceanicus. Several compounds were significantly genetically correlated with either attractiveness or desiccation resistance. Of these compounds, one was negatively genetically correlated with attractiveness but positively genetically correlated with desiccation resistance. Furthermore, scoring each individual's overall CHC profile for its level of attractiveness and desiccation resistance indicated a negative genetic correlation between these multivariate phenotypes. Together, our results provide evidence for a genetic trade-off between sexually and naturally selected functions of the CHC profile. We suggest that the production of an attractive CHC profile may be costly for males, but highlight the need for further work to support this finding experimentally. Genetic covariation between the CHC profile and attractiveness suggests that females can gain attractive sons through female choice.
虽然性展示的生殖益处已经得到了广泛的研究，但我们对于大多数展示特征相关的适应度代价的证据相对有限。昆虫表皮碳氢化合物（CHC）图谱是一种性选择特征，也可以防止脱水。这两个功能被认为是相互对立的，某些化合物的投入增加了吸引力，而牺牲了那些防止水分流失的化合物。我们使用澳大利亚蟋蟀 Teleogryllus oceanicus 在定量遗传框架中研究了这种潜在的权衡。有几个化合物与吸引力或抗干燥能力有显著的遗传相关性。在这些化合物中，有一种化合物与吸引力呈负遗传相关，但与抗干燥能力呈正遗传相关。此外，根据每个个体的 CHC 图谱的吸引力和抗干燥能力对其进行评分，表明这些多变量表型之间存在负遗传相关性。总之，我们的结果为 CHC 图谱的性选择和自然选择功能之间的遗传权衡提供了证据。我们认为，对于雄性来说，产生有吸引力的 CHC 图谱可能是有代价的，但需要进一步的实验工作来支持这一发现。CHC 图谱和吸引力之间的遗传协变表明，雌性可以通过雌性选择获得有吸引力的儿子。
