An animal's gut microbiome, which is the community of bacteria living in its digestive tract, has a web of impacts on the body that it lives in, including cognitive effects, stress responsiveness, and immunocompetence.
 
Most of what we know about animal microbiomes comes from rodent research, and very little is known about those of other animals, such as birds. Morgan Slevin's dissertation research expanded what is known about avian microbiomes in both the lab and field by testing relationships between gut microbiome health, the avian stress response, cognitive performance, and the overall health of the bird. 
 
Drawing upon the lab's strong experience in animal cognition, we tested the relationship between gut microbiome characteristics and interindividual variance in cognitive performance. We also tested for links between the gut microbiome and stress responsiveness, experimentally manipulating stress to examine effects on the microbiome, health, and plumage ornamentation. Ultimately this work will lead to a better understanding of the determinants of animal health and aid in developing ways to index animal population health.