Meeting Abstract
Gut microbial communities play critical roles in metabolism, immune function, and physiology and are shaped by host genetics and environmental factors, including contaminants. Coal combustion represents the largest source of energy and generates toxic waste products. These coal combustion wastes (CCW) are usually stored in landfills and surface impoundments that are appealing habitats for wildlife as they provide permanent sources of freshwater. However, they also contain toxic levels of trace elements, thus putting organisms in direct contact with contaminants. We examined the relative influences of parentage and environmental contaminants on the gut microbiomes of the southern toad (Anaxyrus terrestris). We fertilized eggs from two female toads with sperm from eight males and reared the larvae through metamorphosis in their natal CCW impoundment and in a nearby reference wetland with no history of contamination. Sequencing of the 16S marker gene was used to analyze gut bacterial diversity and population structure within the different gut communities compared to several phenotypic measures. Species richness and diversity were negatively correlated with developmental time (r = =-0.21, -0.19) and positively correlated with growth rate (r = 0.28, 0.27). The identity of the female parent had a significant effect on richness and diversity. Beta diversity was related to rearing environment, developmental time, and female parent within environment. Species richness was greater in the guts of individuals reared in the contaminated environment. These results suggest that host gut microbial diversity could influence fitness related traits and that the role contaminants play in shaping these communities is complex.
