Costs, consequences and context-dependency of intrafamilial conflict

家庭内部冲突的成本、后果和背景依赖性

基本信息

批准号：
NE/C002199/2
负责人：
Nicholas Royle
金额：
$ 10.54万
依托单位：
UNIVERSITY OF EXETER
依托单位国家：
英国
项目类别：
Fellowship
财政年份：
2007
资助国家：
英国
起止时间：
2007 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=NE%2FC002199%2F2
关键词：
Costs consequences context dependency intrafamilial

项目摘要

The environment that an individual experiences during growth and development has profound implications for the future health and fitness of that individual during adulthood. In species that provide parental care offspring are usually reared together in broods, so close relations often provide the social environment in which growth and development takes place. However, because parental care is costly to parents (in time and energy), and availability of environmental resources essential for growth and development of young varies unpredictably, offspring demand for food and other resources often exceeds parental supply. As a consequence there may be conflicts of interest among family members over the supply of these parental resources (parental investment; PI), which affects the amount of resources available to individual offspring. The consequences of such conflicts within families can be pervasive, and have important effects for the diversity and evolution of life-history traits and behaviours such as growth rates, clutch size, sexual attractiveness and begging behaviour. The amount of resources available to individual offspring depends upon the amount of conflict, which is determined by the relatedness of family members and the availability of key resources in the environment. However, although the importance of within-family conflicts for growth, development and fitness is increasingly being recognised, very little is known about the mechanisms that underpin such conflicts, or the interrelationships between resource availability, conflict over these resources and the mechanisms that determine the costs and consequences of conflict. Previous work on zebra finches by the author showed that, although receiving less food, offspring reared under conditions of higher within-family conflict had faster growth compared to siblings reared under lower levels of conflict. As a result these offspring were less attractive as adults, indicating a substantial costs of rapid growth and of family conflict. These costs are most probably a consequence of increased oxidative stress, which occurs when high levels of free radicals, which are by-products of normal metabolic processes, cause damage to various cell components. Antioxidants provide protection against the damaging effects of free radicals. An important component of total antioxidant defence is provided by fat-soluble antioxidants, such as carotenoids and vitamin E, which are derived from the diet. The interaction between dietary availability of antioxidants and within-family conflicts has not previously been considered, but is likely to be important as variation in antioxidant availability determines the trade-off between self-maintenance and investment in growth and reproduction, and hence fitness. This project plans to use brood size manipulations, hand-rearing and parent removal experiments and cross-fostering to tease apart the effects of sexual conflict and sibling competition on growth and fitness of offspring, examine the cost basis of growth through the measurement of oxidative stress and manipulation of dietary antioxidant availability, and establish the behavioural mechanisms that underlie the allocation of PI in relation to the social and environmental context in which they are operating. The work integrates nutrition, reproductive ecophysiology and environmental uncertainty with behavioural ecology in examining the costs and consequences of variation in social and environmental effects early in life on adult health and fitness. If funded, the project would be conducted at the Institute of Biological and Life Sciences at the University of Glasgow, using zebra finches Taeniopygia guttata as a model species.

个人在成长和发展过程中经历的环境对成年期间该人的未来健康和适应性产生了深远的影响。在提供父母护理后代的物种中，通常是在育雏中饲养的，因此亲密的关系通常提供了发生增长和发展的社会环境。但是，由于父母的护理对父母（时间和精力）的昂贵，而对年轻人的增长和发展至关重要的环境资源的可用性差异不佳，因此对食物和其他资源的后代需求通常超过父母的供应。结果，家庭成员在这些父母资源的供应（父母投资； PI）上可能存在利益冲突，这会影响个人后代可用的资源量。家庭内部这种冲突的后果可能普遍存在，并对生活历史的特征和行为的多样性和演变产生重要影响，例如增长率，离合器规模，性吸引力和乞讨行为。各个后代可用的资源数量取决于冲突的数量，这取决于家庭成员的相关性和环境中关键资源的可用性。但是，尽管家庭内冲突对增长的重要性，发展和健身越来越多地得到认可，但对基于此类冲突的机制或资源可用性，对这些资源的冲突以及确定冲突成本和后果的机制之间的相互关系知之甚少。作者对斑马雀科的先前工作表明，尽管收到较少的食物，但在较高的家庭冲突条件下饲养的后代与在冲突水平较低的兄弟姐妹相比，增长速度更快。结果，这些后代作为成年人的吸引力较小，这表明迅速增长和家庭冲突成本。这些成本很可能是氧化应激增加的结果，氧化应激发生在高水平的自由基（是正常代谢过程的副产品）时会损害各种细胞成分时。抗氧化剂可保护自由基的破坏作用。总抗氧化剂防御的重要组成部分是由脂溶性抗氧化剂（例如类胡萝卜素和维生素E）提供的，这些抗氧化剂来自饮食。抗氧化剂的饮食可用性与家庭内冲突之间的相互作用尚未被考虑，但可能很重要，因为抗氧化剂可用性的差异决定了自我维护和对增长和繁殖的投资之间的权衡，从而决定了适应性。该项目计划使用育雏尺寸的操纵，抚养和父母去除实验并进行交叉培养，以分开性冲突和同级竞争对后代的增长和适应性的影响，通过测量氧化压力和操纵饮食中的抗氧化可用性和对环境的饮食抗氧化可用性和对环境的影响，从而研究成本基础。这项工作将营养，生殖生态生理学和环境不确定性与行为生态学结合在一起，以研究生活早期对成人健康和适应性早期社会和环境影响变化的成本和后果。如果资助，该项目将在格拉斯哥大学的生物与生命科学研究所进行，使用斑马雀科taeniopygia guttata作为模型物种。