Grant: Discovery Grants Program - Individual

Phenotypic plasticity is the ability of organisms to alter their development, physiology and/or behaviour in response to cues in their biotic and/or abiotic environment. This phenomenon is generally thought to be adaptive if it leads to individuals adopting a fitness-maximizing strategy that is better suited to local conditions compared to a fixed strategy. Phenotypic plasticity can involve traits subject to natural selection, as well as primary and secondary reproductive traits subject to sexual selection. To date, the study of reproductive plasticity has largely revolved around the causes, limitations, and consequences of plasticity to male reproductive traits, with less attention directed towards females. However, there are countless ways in which female behavioural phenotypes may exhibit plasticity (possibly adaptively) in response to their physical and/or social environments. This proposal focuses on examining the expression of phenotypic plasticity in decisions made by females, and the consequences to themselves, their mates, their offspring, and the population in general. Studies will be conducted using populations of fruit flies (Drosophila melanogaster), a valuable model for the study of reproductive phenotypic plasticity in males, which is also increasingly being used to understand the evolution of decision making. In our populations, reproductive success can be meaningfully quantified, and biotic and/or abiotic environments can be effectively manipulated. Many powerful genetic tools can be used to tease apart the factors involved in mediating phenotypically plastic responses. Planned studies will build on my group's previous discoveries and use tools/techniques we have developed to measure phenotypic plasticity in novel ways. We will measure female preferences (for mates, for oviposition sites) in competitive and non-competitive environments and in environments where we have manipulated the individuals' personal histories. We will examine the impact of the composition/qualities of their social group, and conduct follow up assays of offspring production and fitness. We will also make use of the D. melanogaster cytogentic cloning system that allows us to isolate, replicate, and propagate ~whole haploid genomes, and express them in a random "hemiclonal" genetic backgrounds. By creating numerous clone lines, and producing hemi-clones `on demand', we will be able to explore and quantify the extent of genetic variation present for traits that express phenotypic plasticity. We will be able to compare the phenotypes of hemiclones from different lines, and the phenotypes from each line developing under different conditions, or experiencing different biotic/abiotic environments. This research will provide HQP with the opportunity to develop their scientific skills, and will help fill in important missing pieces of our field's understanding regarding the potential for female Drosophila to respond plastically to environmental variation.