Head Megan L, Fox Rebecca J, Barber Iain
Department of Neuroscience, Psychology and Behaviour, College of Medicine, Biological Sciences and Psychology, University of Leicester, University Road, Leicester, LE1 7RH, United Kingdom.
Division of Evolution, Ecology, and Genetics, Research School of Biology, Australian National University, Canberra, ACT, 2600, Australia.
Evolution. 2017 Jan;71(1):135-144. doi: 10.1111/evo.13091. Epub 2016 Nov 2.
Sexual cues, including extended phenotypes, are expected to be reliable indicators of male genetic quality and/or provide information on parental quality. However, the reliability of these cues may be dependent on stability of the environment, with heterogeneity affecting how selection acts on such traits. Here, we test how environmental change mediates mate choice for multiple sexual traits, including an extended phenotype--the structure of male-built nests - in stickleback fish. First, we manipulated the dissolved oxygen (DO) content of water to create high or low DO environments in which male fish built nests. Then we recorded the mate choice of females encountering these males (and their nests), under either the same or reversed DO conditions. Males in high DO environments built more compact nests than those in low DO conditions and males adjusted their nest structure in response to changing conditions. Female mate choice for extended phenotype (male nests) was environmentally dependent (females chose more compact nests in high DO conditions), while female choice for male phenotype was not (females chose large, vigorous males regardless of DO level). Examining mate choice in this dynamic context suggests that females evaluate the reliability of multiple sexual cues, taking into account environmental heterogeneity.
包括扩展表型在内的性信号，有望成为雄性基因质量的可靠指标和/或提供有关亲代质量的信息。然而，这些信号的可靠性可能取决于环境的稳定性，环境异质性会影响选择如何作用于此类性状。在此，我们测试环境变化如何介导对多种性特征的配偶选择，包括一种扩展表型——雄性三刺鱼建造的巢穴结构。首先，我们控制水中的溶解氧（DO）含量，营造出雄性鱼类筑巢的高溶解氧或低溶解氧环境。然后我们记录了雌性在相同或相反溶解氧条件下与这些雄性（及其巢穴）相遇时的配偶选择。高溶解氧环境中的雄性建造的巢穴比低溶解氧环境中的更紧凑，并且雄性会根据环境变化调整巢穴结构。雌性对扩展表型（雄性巢穴）的配偶选择取决于环境（雌性在高溶解氧条件下选择更紧凑的巢穴），而对雄性表型的选择则不然（无论溶解氧水平如何，雌性都选择体型大、活力强的雄性）。在这种动态背景下研究配偶选择表明，雌性会考虑环境异质性来评估多种性信号的可靠性。
