Abstracts (first author)
Interactions between species shape parental investment in the burying beetle
Parental care studies typically focus on intraspecific interactions occurring during reproductive events, such as between mates or between parents and offspring. Interactions between species are often neglected, yet feedbacks between species may shape parental investment. This is particularly important when parents breed on temporary resources for which there is high competition. The burying beetle Nicrophorus vespilloides breeds on small vertebrate carcasses which they bury and cover in antimicrobial exudates. Investment in antimicrobial exudates increases in response to carcass microbial load. Females investing more in antimicrobial exudates seem to protect their current brood at the cost of future reproduction. Beetles also carry phoretic mites that breed alongside them on a carcass. We investigate interactions between beetles, mites and microbes, and how these affect reproductive strategies in the burying beetle. Using breeding experiments we test whether mites have beneficial or detrimental effects on beetles breeding in carcasses presenting different levels of microbial challenge. To gauge the microbial challenges faced by wild beetles, we use metagenomics to assess the microbiome of prepared and unprepared carcasses. We found that females breeding with mites have lower levels of antimicrobial activity, potentially safeguarding future reproduction. However, male lifespan is reduced when breeding with mites, suggesting that interacting with mites is costly for males. Beetles radically change the microbiome of carcasses: prepared carcasses, relative to unprepared, show a shift towards overrepresentation of Gram negative bacteria. In conclusion, characterizing relationships between species in this system unravels ecological pressures shaping parental investment and trade-offs between future and current reproduction. Using a metagenomics approach we are able to identify key players in the bacterial communities which challenge carrion beetles.