Prior experience affects allocation to current reproduction in a burying beetle

Abstract

The cost of reproduction hypothesis predicts that the level of reproductive investment to current reproduction is constrained by an individual's future reproductive potential or residual reproductive value. Therefore, age, or differences between young and old individuals in residual reproductive value, is expected to influence reproductive investment. However, recent theoretical work suggests that residual reproductive value is also influenced by an individual's state or condition which may in part be determined by prior reproductive experience. We evaluated the reproductive investment of same-aged female burying beetles (Nicrophorus orbicollis) to determine how prior reproductive experience affects current reproduction. Consistent with previous research, females reproducing on low-quality carcasses allocated more to future reproduction by producing smaller offspring and gaining more mass than females on high-quality carcasses. When prior experience was manipulated, females that initially reproduced on a low-quality resource exhibited an accentuated response to a high-quality carcass by producing significantly larger broods of offspring compared with control females reproducing on high-quality carcasses. Conversely, females that initially reproduced on a high-quality carcass and were subsequently presented a low-quality carcass exhibited a decrease in offspring size and an increase in female mass change, indicative of a switch in allocation from current to future reproduction. The change in carcass quality resulted either in terminal investment or reproductive restraint, dependent on prior experience. Our results combined with those of previous papers demonstrate that the level of reproductive investment in burying beetles is influenced by both age and prior reproductive experience. © 2014 The Author.