Predicting the future abundance of organisms requires that we understand how individual reproductive patterns respond to environmental change. Maternal reproductive investment (e.g. the age at first reproduction or the size and number of offspring produced) affects population growth and can thus determine the persistence or extinction of a population. Recent empirical studies suggest that the size and number of offspring produced by females varies among individuals and is shaped simultaneously by multiple factors, including individual condition, resource availability and mate quality. The proposed research will include both theory and empirical work to address maternal investment. The theory will be developed to predict how the factors listed above jointly influence the production of offspring. The predictions from the theory will be tested in a Mexican species of swordtail fish where maternal investment is known to vary among females. Swordtails are ideal for testing this novel theory because they are naturally abundant and their reproductive biology is well studied. The PIs will collaborate with researchers from the US, Mexico, and the UK to address how population ecology and sexual selection interact to shape female reproduction in natural populations of swordtails.
The PIs will involve local high-school students, largely from groups traditionally underrepresented in academia, in the research. They will also provide research opportunities for undergraduates. Finally, by linking theory and data to improve the understanding of individual reproductive patterns, the proposed research will improve predictive models used in the management and conservation of wild populations.
