Mass–size relationships,starvation and recovery in an engorging feeder

The relationships of larval nutritional resources with adult body size, starvation resistance and reproductive decisions are not always clear. Burying beetle larvae with inadequate nutrition are hypothesized to develop into relatively large adults that are able to contest for breeding resources. The trade‐off is that the emerging adult has minimal energy reserves and is more susceptible to starvation, and must gain proportionately more weight after emerging. These hypotheses are investigated in Nicrophorus orbicollis Say. In addition, sex differences in size–mass ratios as well as starvation and recovery in reproductively mature females are examined. The larval mass to adult size ratio is similar in male and female N. Orbicollis and, contrary to prediction, small larvae do not result in adults that are relatively large in size for their mass. Emerging adults of lesser mass resist starvation less well, as expected. Emerging adults of smaller pronotal size gain more relative mass but less absolute mass than larger adults. In reproductively mature adult females, recovery from food deprivation is rapid, with most if not all the weight that is lost during a 9–10‐day starvation period being re‐gained within 1 day of engorging. The ability to gain weight rapidly and regulate body mass provides a nutritional framework for understanding the larva to adult transition and the reproductive and parenting decisions of burying beetles that otherwise would appear to be of too high risk.