Joint Evolution of Energetics, Behaviour and Performance in Wild Mice

点击翻译按钮获取中文摘要

In humans and non-human animals, there are large and consistent among-individual differences in physiology, behaviour, and physical ability (performance). Although individual variation is commonly viewed as the raw material upon which natural selection acts, it can also be the result of selection itself because alternative strategies are commonly favoured within a population. For example, different trait combinations can result in equivalent reproductive success due to environmental heterogeneity over space and time. While predictable or stable environments favour individuals who adopt a “slow” pace of life (i.e., late maturation, small litters, long life), unpredictable or unstable environments favour individuals who adopt a “fast” pace of life (i.e., early maturation, large litters, short life). In turn, variation along a “slow-fast” continuum should affect suites of co-adapted metabolic, behavioural, and performance traits that jointly evolve to support different paces of life. Although co-adaptation is a key concept in evolution and can potentially explain how individual differences are generated and maintained, empirical studies showing co-adaptation are scarce. The goal of this proposal is to test for co-adaptation among metabolic, behavioural, and performance traits along the slow-fast pace of life continuum. To do so, we will quantify how natural selection acts on various metabolic, behavioural, performance, and life-history traits as well as quantify the multivariate quantitative genetic architecture of these traits. Specifically, we will conduct a long-term, individual-based study of wild white-footed mice, a relatively common, well studied, and easy to capture North American rodent. We will install nest boxes which mice will use as daytime refuges and for nesting during reproduction. Regular visits of these nest boxes, in combination with live trapping and genetic analyses, will allow precise quantification of survival and reproductive success. Moreover, individuals will be recaptured several times throughout their lives to quantify different aspects of their phenotypes, such as basal metabolic rate, aerobic capacity, sprint speed, endurance, agility, activity, boldness, and exploratory behaviour. The resulting dataset will allow testing whether these traits are 1) under correlational selection, which would favour co-adaptation, and 2) functionally integrated (genetic covariance), which would indicate co-adaptation. In doing so, this research program will not only have a significant impact on our understanding of how co-variation among complex traits is maintained, but will also offer a unique environment for training young scientists in a wide range of disciplines with different techniques valuable for jobs in academia, environmental consultancy, veterinary sciences, wildlife biology, conservation, nature museums, and parks.