We will explore how organisms respond and adapt to complex, stressful environments by examining the gene activity of a marine invertebrate, the copepod Tigriopus californicus. When challenged with copper, temperature and salinity stress, we observe different levels of survivorship: more individuals from a southern population are likely to survive than from a northern population. We will compare the set of active genes (RNA) specific to the responses of two populations under both single and combined stress. This research explores the consequences of general and specific stress responses: we hypothesize that some genes respond to just one stress while other genes are part of a shared response system. Interaction between these responses could reduce the effect of an additional stress or compound the problem. In resilient and vulnerable populations, we will observe differences in gene activity that may explain how they try to adapt to multiple challenges. Linking the results of this project with genetic analyses will frame adaptation and stress-tolerance, comparing both the gene and its activity response. This project will answer critical questions about how species deal with stressful environments that present simultaneous challenges.
Exploring population-wide variation and the context of stressful natural environments will be key to understanding organism-habitat interactions, and is increasingly important in light of climate changes. Integrative approaches that identify these compounded responses and the biological mechanisms at play will provide a robust context for understanding the effects of pollution and contamination. This research will also identify genetic activity that makes one population more resilient than another in complex environments.