Data from: Maternal effects and population regulation: maternal density-induced reproduction suppression impairs offspring capacity in response to immediate environment in root voles Microtus oeconomus
Bian, Jiang-Hui et al. (2015), Data from: Maternal effects and population regulation: maternal density-induced reproduction suppression impairs offspring capacity in response to immediate environment in root voles Microtus oeconomus, Dryad, Dataset, https://doi.org/10.5061/dryad.c7885
1. The hypothesis that maternal effects act as an adaptive bridge in translating maternal environments into offspring phenotypes and thereby affecting population dynamics has not been studied in the well-controlled fields. 2. In this study, the effects of maternal population-density on offspring stress axis, reproduction and population dynamics were studied in root voles (Microtus oeconomus). Parental enclosures for breeding offspring were established by introducing 6 adults per sex into each of 4 (low density) and 30 adults per sex into each of another 4 (high density) enclosures. Live-trapping started 2 weeks after. Offspring captured at age of 10-20 days were removed to laboratory, housed under laboratory conditions until puberty, and subsequently used to establish offspring populations in these same enclosures, after parental populations had been removed. Offspring from each of the 2 parental sources were assigned into 4 enclosures with 2 for each of the 2 density treatments used in establishing parental populations (referred to as LL and LH for maternally-unstressed offspring, assigned in low- and high-density, and HL and HH for maternally-stressed offspring, assigned in low- and high-density). Fecal corticosterone metabolites (FCM) levels, offspring reproduction traits and population dynamics were tested following repeated live-trapping over 2 seasons. 3. Differential fluctuations in population size were observed between maternally density-stressed and unstressed offspring. Populations in LL and LH groups changed significantly in responding to initial density, and reached the similar levels at beginning of the second trapping season. Populations in HL and HH groups, however, were remained relatively steady, and in HL group the low population size was sustained until end of experiment. Maternal density-stress was associated with FCM elevations, reproduction suppression, and body mass decrease at sexual maturity in offspring. The FCM elevations and reproduction suppression were independent of offspring population density and correlated with decreased offspring quality. 4. These findings indicate that intrinsic state alterations induced by maternal stress impair offspring capacity in response to immediate environment, and these alterations are likely mediated by maternal stress system. The maladaptive reproduction suppression seen in HL group suggests intrinsic population density as one of ecological factors generating delayed density-dependent effects.