Tolerance, Resistance, and Virulence
We spend a lot of time wondering what makes pathogens costly to their host. While theory predicts parasites should negatively impact their host, there is a lot of variation in nature. This can partially be explained by hosts responding differently to infection. For my master's, we used an integrated approach to tease apart whether Plasmodium azurophilum (a type of lizard malaria, pictured below) was costly to its main host, Anolis gundlachi (a Caribbean lizard host, pictured below) and how the host is responding to infection. We used physiological, immunological, and behavioral experiments to determine the host-parasite relationship. We found that infected anoles had a greater probability of capitalizing on food resources when competing against non-infected conspecifics while having no negative impacts of infection on fitness related attributes.
An example of A. gundlachi males competing over a common food resource
Cannibalism and Disease Spread
Cannibalism is thought to be rare in many animal taxa due to many risk factors including the potential spread of infectious disease. However, in nature we observe a wide taxonomic spread in the practice of cannibalism within many different species regardless of the risk of transmission of pathogens. In our review, Van Allen et al. 2017, we highlighted the ways in which cannibalism could actually decrease disease spread rather than promote it. We now hope to continue this work to see how eating your best friend could save you from impending doom of parasitic infection.