Title: From individuals to populations: the impact of host traits on parasite transmission and distribution
Abstract:
Host traits like demographics, behavior, density, and resource acquisition can influence parasite spread and growth within host populations. While previous work has emphasized how host variation in traits impact individual disease outcomes, we lack a broader framework linking host traits to multiple scales of host-parasite interactions. We use a guppy and monogenean host-parasite system to understand the dynamic interactions between host ecology and parasite infection across multiple scales. We established experimental epidemics to establish how host traits impact the spread of parasites and how parasite infection can feedback to impact host behavior. From these experiments, we saw that the transmission of parasites was linked to the infection intensity of the donor host and individual sociality. Additionally, females were more likely to become infected than males, building on previous work showing that female guppies tend to be more social and more tolerant to gyrodactylids than males. We found limited evidence of behavioral change after donor introduction at the individual level but found host groups changed their behavior overall to reflect increased avoidance of infected hosts. We further used field-based observational studies to see how scaling up these host traits to the population level can impact how parasites are distributed among their hosts. We found that Gyrodactylus worms were less aggregated than expected and parasites were less aggregated on male guppies in our system. Overall, we see that individual host traits, particularly host sex variation, can be critical to understanding the spread and distribution of parasites on larger scales.
Stephenson Lab
Wednesday, January 31st, 2023
12:00PM
Langley A219B