Mitchell J, Cant M A, Nichols H J
School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool L3 3AF, UK.
College of Life and Environmental Sciences, University of Exeter, Penryn Campus, Cornwall TR10 9FE, UK.
Biol Lett. 2017 Nov;13(11). doi: 10.1098/rsbl.2017.0441.
Among mammals, scent has long been known to encode oestrus; however, in many species, detecting pregnancy may also be important in terms of both competition and mate-choice. Here, we show, through odour presentation experiments, that pregnancy is discernible via scent by both sexes in the cooperatively breeding banded mongoose, Males spent more time investigating and were more likely to scent mark the odours of non-pregnant females, compared to pregnant females. Females showed increased levels of scent marking when odours were of the same reproductive state as themselves. These results present the first direct demonstration that pregnancy is detectable via scent in wild cooperative breeders. Detecting pregnancy may be particularly important in cooperative breeders as, in addition to the competition between males for receptive mates, there is also intense competition between females for access to alloparental care. Consequently, dominant females benefit from targeting reproductive suppression towards subordinates that represent direct threats, such as pregnant females.
在哺乳动物中，长期以来人们都知道气味能编码发情期；然而，在许多物种中，检测怀孕情况在竞争和配偶选择方面可能也很重要。在这里，我们通过气味呈现实验表明，在合作繁殖的带状猫鼬中，两性都能通过气味辨别怀孕情况。与怀孕雌性相比，雄性会花更多时间去探究，并且更有可能对未怀孕雌性的气味进行气味标记。当气味与自身处于相同生殖状态时，雌性的气味标记水平会增加。这些结果首次直接证明，在野生合作繁殖动物中可以通过气味检测怀孕情况。在合作繁殖动物中，检测怀孕情况可能尤为重要，因为除了雄性为争夺可受孕配偶而进行竞争外，雌性之间为获得异亲照料也存在激烈竞争。因此，优势雌性通过对诸如怀孕雌性等构成直接威胁的从属雌性进行生殖抑制而获益。
