DISSERTATION RESEARCH: Does Hormone Provisioning Link Maternal Social Environment and Offspring Phenotype?

论文研究：激素供应是否与母亲的社会环境和后代表型有关？

• 批准号: 1601455
• 负责人: Elizabeth Tibbetts
• 金额: $ 1.6万
• 依托单位: Regents of the University of Michigan - Ann Arbor
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-06-01 至 2018-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1601455&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Does; Hormone; Provisioning

In animals, when ones' body and behavior are matched to the environment success is maximized. Animals often rely on steroid hormones to adapt to the environments they are in. But in young individuals small differences in the concentration of hormones during development can profoundly alter later survival and behavior. During development a mother's hormone levels impact her developing offspring, and therefore impact more than her own immediate survival but also that of the young she produces. Many studies have tested the idea that steroid hormones provided by mothers to their offspring could help offspring exploit their later adult environment. However, these studies have used animals that take care of their offspring after birth. Can mothers use steroid hormones alone to optimize offspring, or is parenting behavior also necessary? This project will investigate that question by measuring the effects of a steroid hormone on offspring development and survival in an insect species that provides no parental care to its offspring. The results will show whether mothers can use steroid hormones to prime their offspring for future behavioral environments without relying on parental care. Because every mother transmits hormones to her offspring regardless of species, the results of this study will amplify our general understanding of how hormones function across generations. As such, it will likely be especially relevant to conservation of endangered species and environments, and individualized medicine. This broad applicability will also facilitate outreach to local K-12 students and findings will be presented to the scientific community through publications and presentations. This study will investigate maternal effects and aggressive behavior in an invertebrate (Acheta domesticus, the house cricket) that provides no care to offspring, but which naturally experiences variable social environments. Previous data shows that higher levels of ecdysteroid hormones (ESH) in eggs are associated with increased fitness for hatchlings. Proposed research addresses the question of whether and to what extent parents that have no later contact with their offspring can alter the development and behavioral phenotype of said offspring in response to social environment and through endocrine maternal effects alone. Female house crickets will be raised in four social environments (high and low total density, high female density and high male density), and their egg ESH deposition and total reproductive output will be measured, also. Research proposed here will disentangle the effects of maternal hormone provisioning and parental care on offspring life history by measuring hormone provisioning in a system without parental care. This work will also provide more information about ecological and evolutionary functions of ecdysteroid hormones (ESH), which have until now been studied primarily in the context of embryogenesis and molting and are generally underappreciated as mediators of long-term 'organizational' effects. Finally, this research tests the current behavioral endocrinology framework established using vertebrate study systems by considering hypotheses in the independently evolved insect endocrine system.

对于动物来说，当一个人的身体和行为与环境相匹配时，成功率就会最大化。动物通常依靠类固醇激素来适应它们所处的环境。但对于年轻个体来说，发育过程中激素浓度的微小差异可能会深刻地改变以后的生存和行为。在发育过程中，母亲的激素水平会影响她正在发育的后代，因此不仅会影响她自己的直接生存，还会影响她所生下的孩子的生存。许多研究已经验证了这样的观点：母亲为后代提供的类固醇激素可以帮助后代利用成年后的环境。然而，这些研究使用的是在出生后照顾后代的动物。母亲可以单独使用类固醇激素来优化后代，还是养育行为也有必要？该项目将通过测量类固醇激素对不为其后代提供亲代照顾的昆虫物种的后代发育和生存的影响来研究这个问题。研究结果将表明母亲是否可以使用类固醇激素来为后代做好未来行为环境的准备，而无需依赖父母的照顾。由于无论物种如何，每位母亲都会将激素传递给后代，因此这项研究的结果将加深我们对激素如何跨代发挥作用的一般理解。因此，它可能与濒危物种和环境的保护以及个体化医疗特别相关。这种广泛的适用性还将促进对当地 K-12 学生的推广，研究结果将通过出版物和演示文稿向科学界展示。这项研究将调查无脊椎动物（家蟋蟀）的母体影响和攻击行为，这种无脊椎动物不会照顾后代，但自然会经历可变的社会环境。先前的数据表明，鸡蛋中较高水平的蜕皮类固醇激素（ESH）与幼体的健康状况增强有关。拟议的研究解决了以下问题：后来与后代没有接触的父母是否以及在多大程度上可以改变所述后代的发育和行为表型，以响应社会环境并仅通过内分泌母体效应。雌性家蟋蟀将在四种社会环境（高和低总密度、高雌性密度和高雄性密度）中饲养，并且还将测量它们的卵 ESH 沉积和总繁殖产量。这里提出的研究将通过测量没有父母照顾的系统中的激素供应来阐明母体激素供应和父母照顾对后代生活史的影响。这项工作还将提供更多关于蜕皮类固醇激素（ESH）的生态和进化功能的信息，迄今为止，这些激素主要是在胚胎发生和蜕皮的背景下进行研究的，并且作为长期“组织”效应的中介者通常被低估。最后，本研究通过考虑独立进化的昆虫内分泌系统的假设，测试了当前使用脊椎动物研究系统建立的行为内分泌学框架。