Antimicrobial strategies in burying beetles breeding on carrion

Abstract

Rich and ephemeral resources, such as carrion, are a source of intense interspecific competition among animal scavengers and microbial decomposers. Janzen [Janzen DH (1977) Am Nat 111:691-713] hypothesized that microbes should be selected to defend such resources by rendering them unpalatable or toxic to animals, and that animals should evolve counterstrategies of avoidance or detoxification. Despite the ubiquity of animal-microbe competition, there are few tests of Janzen's hypothesis, in particular with respect to antimicrobial strategies in animals. Here, we use the burying beetle Nicrophorus vespilloides, a species that obligately breeds on carcasses of small vertebrates, to investigate the role of parental care and avoidance as antimicrobial strategies. We manipulated competition between beetle larvae and microbes by providing beetles with either fresh carcasses or old ones that had reached advanced putrefaction. We found evidence for a strong detrimental effect of microbial competition on beetle reproductive success and larval growth. We also found that parental care can largely compensate for these negative effects, and that when given a choice between old and fresh carcasses, parents tended to choose to rear their broods on the latter. We conclude that parental care and carcass avoidance can function as antimicrobial strategies in this species. Our findings extend the range of behavioral counterstrategies used by animals during competition with microbes, and generalize the work of Janzen to include competition between microbes and insects that rely on carrion as an obligate resource for breeding and not just as an opportunistic meal.animal-microbe interactions ͉ parental care ͉ resource competition

Asynchronous hatching in a nonavian species: a test of the hurry-up hypothesis

“…Consequently, there was no difference in the timing of larval dispersal between females breeding on decomposed carcasses and fresh carcasses. The latter result contrasts with a previous study on the same species, 370 which found that dispersal occurred later on decomposed carcasses than on fresh carcasses (Rozen et al 2008). The different results of this previous study may reflect differences in methodology as it used experimental foster broods that were completely synchronous and smaller than our natural broods (Rozen et al 2008), while we allowed females to rear their own broods without interference.…”

Social attraction mediated by fruit flies' microbiome

“…While adult and larval fruit flies can taste a substrate in order to obtain some information about food quality, taste alone cannot indicate the presence of all essential nutrients. Furthermore, fruit flies are under intense competition with numerous species of fungi and bacteria for feeding on fallen fruit, and many microbes produce secondary compounds that harm other microbes as well as many other animals, including fruit flies (Janzen, 1977;Demain and Fang, 2000;Rohlfs et al, 2005;Rozen et al, 2008). It is thus possible that microbiome volatiles signal to flies the availability of a food substrate with suitable microbial species.…”

Gut Microbiota Colonization and Transmission in the Burying Beetle Nicrophorus vespilloides throughout Development

“…This system is particularly interesting for addressing these questions given the peculiar life history of these organisms. Nicrophorus beetles are reared on decomposing carrion where they encounter and ingest high densities of microbes (25)(26)(27)(28)(29). Eggs are laid in the soil near the carcass (25).…”