Species‐specific manipulation of microbially derived volatiles by burying beetle parents

Abstract Hosts and microbes interact in dynamic relationships that can alter the volatile profile emitted by the microbial community. The extent to which closely related species diverge in these relationships is not well known. Burying beetles associate with a rich microbial community that is present on their breeding resource, a small vertebrate carcass. Prior work demonstrated that Nicrophorus orbicollis manages the microbial community during parental care to alter the volatile profile emanating from the nest, reducing cues for competitors that would usurp the resource. The present study extended this work to N. marginatus to first determine the distinctive volatile cues that attract this species to carrion and then to examine whether parents altered the volatile profile as a competitive adaptation. In two field tests, Nicrophorus marginatus was highly attracted to mouse carcasses supplemented with the chemical dimethyl disulphide compared with control carcasses or carcasses supplemented with methyl thiocyanate or dimethyl trisulphide. There was no synergistic effect on attraction when combining dimethyl disulphide and dimethyl trisulphide. Headspace collection followed by gas chromatography–mass spectrometry analyses revealed that parents that prepared a carcass reduced the emission of dimethyl disulphide by 70.6%. Methyl thioacetate and methyl thiocyanate were also reduced by carcass preparation, while dimethyl trisulphide and dimethyl tetrasulphide were not. The results suggest that the congeners N. marginatus and N. orbicollis interact with their microbial communities in species‐specific ways to enhance competitive ability.