The Adaptive Potential of Maternal Stress as a Driver of Variation in Offspring Fitness in a Free-living Animal

该项目解决了一个对生物和医学领域都至关重要的问题；母亲所经历的压力是如何影响她的后代的？具体来说，该项目研究了母亲压力如何改变后代的形态、行为和生理，以及这些变化最终如何影响后代的生存——在高压力和良性环境中。科学家们挑战了人们普遍认为的母亲压力会对后代产生负面影响的观点。他们提出，母亲的压力为后代应对高压力条件做好了准备。这个项目在蜥蜴身上测试压力母亲的后代是否在高压力环境（包括掠食性的入侵火蚁）中生存得更好，在低压力环境中生存得更差，以及来自压力环境的蜥蜴是否能够更好地应对压力。通过测试暴露于新型掠食性蚂蚁的后果，该项目解决了环境变化影响的全球问题。研究结果将为进口红火蚁的预测和管理提供信息，红火蚁目前威胁着美国南部许多脊椎动物的生存。这项工作将利用社区对这些入侵火蚁的强烈兴趣，让学生和社区参与科学。调查人员将与南阿拉巴马州的女童子军和宾夕法尼亚州的公园森林中学合作，开发涉及当地社区和学龄学生的科学相关教育工具。母亲的压力是影响后代表型的驱动因素，传统上认为这对机体适应性是“昂贵的”。这个项目测试了一个假设，即捕食者诱导的母体压力适应性地使后代为母体所经历的高风险环境做好准备。它研究了压力母亲的后代是否能在高风险环境中更好地生存，以及可能影响生存差异的潜在机制（形态、生理和行为）。研究人员将结合实验室操作和自然和半圈养的野外实验，使用自由生活的栅栏蜥蜴（猎物）和火蚁（捕食者）。在将后代释放到高或低捕食者风险环境中并测量自然存活率之前，将通过实验控制母体和卵子的应激水平并测量由此产生的后代表型。通过在从火蚁入侵和非入侵地点捕获的栅栏蜥蜴中测试这些假设，本项目评估了风险进化史对这些影响强度的影响。该项目将有助于理解在进化和生态相关环境中母亲压力对后代适应性的影响，并挑战压力后果必然是负面的假设。拟议的项目解决了入侵红火蚁的全球重要问题。调查人员将与南阿拉巴马州的女童子军和宾夕法尼亚州的公园森林中学合作，开展与科学相关的课堂活动，教育当地社区和学龄学生。拟培养硕士生1名、博士生1名、博士后1名、本科生4名、早期职业科学家1名。

This project addresses a question of fundamental importance to both the biological and medical fields; how does the stress a mother experiences impact her offspring? Specifically, this project examines how maternal stress alters the morphology, behavior and physiology of offspring, and how these changes ultimately affect offspring survival - in both highly stressful and benign environments. The scientists challenge the widely held belief that maternal stress negatively affects offspring. They propose that maternal stress prepares offspring for high stress conditions. This project tests, in lizards, whether offspring of stressed mothers will survive better in high stress environments (containing predatory, invasive fire ants), worse in low stress environments and if lizards that come from stressful environments are better able to deal with stress. By testing the consequences of exposure to novel predatory ants, this project addresses the global issue of the impacts of environmental change. The results work will inform the prediction and management of the imported red fire ant, which currently threatens the survival of many vertebrates in the southern USA. This work will leverage the strong community interest in these invasive fire ants to engage students and the community in science. The investigators will partner with the Girl Scouts of Southern Alabama and Park Forest Middle School in Pennsylvania to develop science related education tools involving both the local community and school-aged students.Maternal stress is a driving factor affecting offspring phenotypes and is traditionally viewed as 'costly' to organismal fitness. This project tests the hypothesis that predator-induced maternal stress adaptively prepares offspring for the high-risk environment experienced by the mother. It examines whether offspring from stressed mothers survive better in high-risk environments and the potential mechanisms (morphology, physiology, and behavior) that may affect survival differences. The investigators will use a combination of laboratory manipulations, and natural and semi-captive field experiments using free-living fence lizards (prey) and fire ants (predator). Maternal and egg stress levels will be experimentally manipulated and resulting offspring phenotype measured before offspring are released into high or low predator risk environments and natural survival measured. By testing these assumptions in fence lizards captured from fire ant invaded and non-invaded sites, this project evaluates the influence of an evolutionary history of risk on the strength of these effects. This project will contribute to the understanding of the consequences of maternal stress for offspring fitness within evolutionary and ecologically relevant environments, and challenge the assumption that consequences of stress are necessarily negative. The proposed project addresses the globally-important issue of invasive red fire ants. Investigators will partner with the Girl Scouts of Southern Alabama and Park Forest Middle School in Pennsylvania, developing science related classroom activities, educating the local community and school-aged students. The proposed work supports the training of 1 Masters and 1 Doctoral student, 1 post-doctoral fellow, 4 undergraduates, and an early career scientist.