Effects of inbreeding on behavioural plasticity of parent-offspring interactions in a burying beetle

Inbreeding depression is defined as a fitness decline in progeny resulting from mating between related individuals, the severity of which may vary across environmental conditions. Such inbreeding-by-environment interactions might reflect that inbred individuals have a lower capacity for adjusting their phenotype to match different environmental conditions better, as shown in prior studies on developmental plasticity. Behavioural plasticity is more flexible than developmental plasticity because it is reversible and relatively quick, but little is known about its sensitivity to inbreeding. Here we investigate effects of inbreeding on behavioural plasticity in the context of parent-offspring interactions in the burying beetle Nicrophorus vespilloides. Larvae increase begging with the level of hunger, and parents increase their level of care when brood sizes increase. Here we find that inbreeding increased behavioural plasticity in larvae, reducing their time spent associating with a parent...