Risk-Management Ecology Lab, Department of Ecology, Evolution & Behavior, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel.
Ecology. 2023 Feb;104(2):e3869. doi: 10.1002/ecy.3869. Epub 2022 Dec 9.
Many animals exhibit size assortative mating (SAM), but how predation affects it remains largely unknown. We hypothesized that predation risk may turn prey less choosy, disrupting SAM, or reduce the expected reproductive value of mates, maintaining SAM but with different size ratio between mates. Using a manipulative field experiment, we found that desert isopods under risk of scorpion predation maintained SAM, but that males that choose and fight over females were on average smaller for a given female size. Less pairs were formed in risky sites, but there were no differences in female sizes and progeny number, size and age near and away from scorpion burrows. Our complementary behavioral experiments revealed that bigger males stayed longer near safe burrows, and won more male-male contests than smaller conspecifics. Our findings highlight that prey can anticipate future costs of predation and use this information to assess the expected reproductive value of mates.
许多动物表现出大小选择性交配（SAM），但捕食如何影响它在很大程度上仍是未知的。我们假设，捕食风险可能会使猎物变得不那么挑剔，从而破坏 SAM，或者降低配偶的预期繁殖价值，从而维持 SAM，但配偶之间的大小比例不同。通过一项操纵性野外实验，我们发现，处于蝎子捕食风险下的沙漠等足类动物维持了 SAM，但对于给定的雌性大小，选择并争夺雌性的雄性平均体型较小。在风险较高的地点形成的配对较少，但在蝎子洞穴附近和远离洞穴的地方，雌性大小和后代数量、大小和年龄均无差异。我们的补充行为实验表明，体型较大的雄性在安全的洞穴附近停留的时间更长，并且比体型较小的同种雄性赢得更多的雄性竞争。我们的研究结果表明，猎物可以预测未来的捕食成本，并利用这些信息来评估配偶的预期繁殖价值。
