Grant: Discovery Grants Program - Individual

Modular organisms (e.g. plants, fungi, algae) dominate the planet in terms of biomass but our understanding of their ecology and evolution lags far behind that of unitary, multicellular organisms (e.g. most animals). The research proposed here will include the development of new models of sexual fitness in modular organisms and test predictions from our previous modelling efforts using controlled experiments and studies of natural populations. *Modularity and mating Terrestrial ecosystems are dominated by long-lived plants, most of which possess some capacity for clonal growth. However, the effects of clonality on sexual fitness are poorly understood. The research proposed here involves definitive tests of our previous models developed to clarify the effects of clonality on sexual fitness. I will train HQP to conduct these tests by measuring mating success as functions of the size and spatial arrangement of clones in natural, experimental, and simulated populations. *Sexual selection in modular organisms Sexual selection is a widespread feature of sexually reproducing organisms but there has been little progress in applying the concept to plants. A new method developed in the lab has the potential to transform the study of sexual selection in natural populations of plants (and most modular organisms) but it has yet to be thoroughly tested. The proposed research will involve conducting these tests in natural and experimental populations. Support for our measure would open new opportunities for studying sexual selection in plants and enable comparisons with unitary animals for which we have strong evidence for far-reaching effects.*Modularity, life-history, and the evolution of reproductive systems Reproductive strategies influence gene transmission, population demography, and net rates of evolutionary diversification. Understanding the evolution of reproductive strategies is therefore key to solving Darwin's ""abominable mystery"" - the rapid diversification of the flowering plants. Previous, over-simple models for the evolution of separate sexes yielded predictions that do not fit with our previous empirical results. To resolve this we will develop evolutionary-stable strategy models that include more realistic assumptions of life-history trade-offs in modular organisms and experimentally test model predictions to examine the consequences of these trade-offs for the evolution of separate sexes.*Impact Ignoring modularity and iterative growth has impeded progress in understanding the ecology and evolution of the organisms that dominate terrestrial ecosystems the flowering plants. The major focus of research in my lab has been to rectify this using modelling and experimentation. These efforts have provided a wealth of new directions for further studies and a successful track record of high-level student training for STEM careers in Canada.