tailieunhanh - Mechanisms for delayed density-dependent reproductive traits in field voles, Microtus agrestis: the importance of inherited environmental effects

As the international community moves toward a more robust recognition of both the human rights of disabled persons and the reproductive rights of women, the intersection comprising the right of disabled women to reproductive freedom must be given full atten- tion. This briefing paper proposes a human rights framework for considering the repro- ductive rights of women with disabilities, taking into consideration international human rights laws and instruments and global consensus documents. We recognize, and respect, that there are differences of opinion among — and within — the disabilities rights, women’s rights, and human right communities. Our objective is. | OIKOS 95 185-197. Copenhagen 2001 Mechanisms for delayed density-dependent reproductive traits in field voles Microtus agrestis the importance of inherited environmental effects Torbjorn Ergon James L. MacKinnon Nils Chr. Stenseth Rudy Boonstra and Xavier Lambin Ergon T. MacKinnon J. L. Stenseth N. C. Boonstra R. and Lambin X. 2001. Mechanisms for delayed density-dependent reproductive traits in field voles Microtus agrestis the importance of inherited environmental effects. - Oikos 95 185-197. Reproductive traits of voles vary with the phases of the population density fluctuations. We sought to determine whether the source of this variation resides in the individuals or in their environment. Overwintering field voles Microtus agrestis from two cyclic out-of-phase populations increase and peak phases were sampled in early spring and bred in the laboratory for two generations under standardised conditions with ambient light and temperature. Monitoring of the source populations by capture-mark-recapture showed large differences in reproductive performance. In the increase area reproduction started six weeks earlier the probability of maturation of young-of-the-year was more than ten times higher during mid-summer and reproduction continued nearly two months later in the autumn than in the peak area. These differences were not found to be associated with a difference in age structure of overwintered animals between the two areas assessed by the distribution of eye lens masses from autopsy samples . Although the population differences in reproductive traits were to some degree also present among the overwintered animals in the laboratory we found no difference in reproductive traits in the laboratory-born generations. There was a strongly declining seasonal trend in probability of sexual maturation both in the field and in the laboratory under ambient light conditions. However in the field there were large population differences in the steepness of the seasonal decline