Data from: Environmental sources of bacteria and genetic variation in behavior influence host-associated microbiota

In many organisms, host-associated microbial communities are acquired
horizontally after birth. This process is believed to be shaped by a
combination of environmental and host genetic factors. We examined whether
genetic variation in animal behavior could affect the composition of the
animal’s microbiota in different environments. The freshwater crustacean
Daphnia magna is primarily planktonic but exhibits variation in the degree
to which it browses in benthic sediments. We performed an experiment with
clonal lines of D. magna showing different levels of sediment-browsing
intensity exposed to either bacteria-rich or bacteria-poor sediment or
whose access to sediments was prevented. We found that the bacterial
composition of the environment and genotype-specific browsing intensity
together influence the composition of the Daphnia-associated bacterial
community. Exposure to more diverse bacteria did not lead to a more
diverse microbiome, but greater abundances of environment-specific
bacteria were found associated with host genotypes that exhibited greater
browsing behavior. Our results indicate that, although there is a great
deal of variation between individuals, behavior can mediate
genotype-by-environment interaction effects on microbiome composition.