My current research aims to determine if thermal performance is constrained across the metamorphic boundary. A lack of constraint in thermal tolerance may be indicative of adaptive decoupling – the process in which an organism exhibiting a complex life cycle may evolve different strategies to cope with some stress in distinct life stages. This would mean that complex life cycles, at least partially, have evolved to allow for the independent evolution of distinct life stages. To test for this, I will be using the Drosophila Genetic Reference Panel, or the DGRP. The DGRP are a set of approximately 200 isogenic lines of Drosophila melanogaster. Because each line is sequenced, determining loci associated with performance in each life stage is possible and relatively easy to perform using Genome-wide Association Studies (GWAS). My first goal is to estimate the amount of genetic correlation for thermal performance in each line to determine how much (or how little) genetic constraint exists for this phenotype. Again, a lack of genetic correlation is indicative of little constraint, allowing for independent evolutionary strategies across ontogeny.
At this moment, the future of this research is undecided. However, elucidating the actual mechanisms underlying either strong genetic constraint or adaptive decoupling is a major goal for this project. At the surface, I would like to determine how differing morphologies across ontogeny either help or hinder adaptive decoupling.