Data from: When the mean no longer matters: developmental diet affects behavioral variation but not population averages in the house cricket (Acheta domesticus)

Despite recent progress elucidating the genetic basis for behavioral variation, the effects of the developmental environment on the maintenance and generation of behavioral variation across multiple traits remains poorly resolved. We investigated how nutritional status during development affected behavioral variation and covariance between activity in an open field test and response to cues of predator presence in the house cricket (Acheta domesticus). We provided 98 juvenile crickets with either a high or low quality diet during development throughout which we measured body mass, activity in a modified open-field and response to predator excreta twice every week for three weeks. Diet quality affected growth rate but not average activity or response to cues of predator presence, nor the correlation between the two. However, repeatability (τ) in response to cues of predator presence was reduced by 0.24 in individuals exposed to the high quality diet versus the low quality diet. Larger individuals also increased their response to predator cues when reared on a high quality diet, suggesting negative feedbacks between growth rate and antipredator behaviors. Our results also indicate that changes in the developmental environment are not sufficient to collapse behavioral syndromes, suggesting a genetic link between activity and predator cue response in house crickets, and that nutritional stress early in life can lead to more consistent behavioral responses when individuals faced predatory threats. Our results demonstrate that subtle differences in the quality of the environment experienced early in life can influence how individuals negotiate behavioral and life-history trade-offs later in life.尽管目前在阐明行为变异的遗传基础方面已取得诸多进展，但发育环境对多性状下行为变异的维持与产生的影响，仍未得到清晰解析。本研究以家蟋蟀（Acheta domesticus）为实验对象，探究了发育阶段的营养状况如何影响行为变异，以及旷场实验（open field test）中的活动水平与捕食者线索响应之间的协方差。我们为98只幼年家蟋蟀提供高质量或低质量的发育日粮，并在为期三周的实验中，每周两次测量其体重、改良旷场活动量以及对捕食者排泄物的响应。结果显示，日粮质量仅影响个体生长速率，并未改变其平均活动水平或捕食者线索响应，亦未影响二者间的相关性。然而，相较于饲喂低质量日粮的个体，饲喂高质量日粮的家蟋蟀，其捕食者线索响应的重复性（repeatability, τ）降低了0.24。此外，饲喂高质量日粮的体型更大个体，其捕食者线索响应强度有所提升，这表明生长速率与反捕食行为之间存在负反馈调控。本研究结果还表明，发育环境的改变不足以瓦解行为综合征，这提示家蟋蟀的活动水平与捕食者线索响应之间存在遗传关联；同时发现生命早期的营养胁迫可使个体在面临捕食威胁时，产生更为稳定的行为响应。综上，本研究证实，生命早期所经历的环境质量的细微差异，可影响个体后续应对行为与生活史权衡的策略。