Data from: Selfish pups: weaning conflict and milk theft in free-ranging dogs

Parent-offspring conflict theory predicts the emergence of weaning conflict between a mother and her offspring arising from skewed relatedness benefits. Empirical observations of weaning conflict have not been carried out in canids. In a field-based study on free-ranging dogs we observed that nursing/suckling bout durations decrease, proportion of mother-initiated nursing bouts decrease and mother-initiated nursing/suckling terminations increase with pup age. We identified the 7th - 13th week period of pup age as the zone of conflict between the mother and her pups, beyond which suckling solicitations cease, and before which suckling refusals are few. We also report for the first time milk theft by pups who take advantage of the presence of multiple lactating females, due to the promiscuous mating system of the dogs. This behaviour, though apparently disadvantageous for the mothers, is perhaps adaptive for the dogs in the face of high mortality and competition for resources.

亲子冲突理论（Parent-offspring conflict theory）预测，由于亲缘收益不对称，母代与子代之间会出现断奶冲突（weaning conflict）。目前尚未在犬科动物（canids）中开展过针对断奶冲突的实证观测研究。本研究针对自由散养家犬开展野外实地调查，结果显示：随着幼崽年龄增长，单次哺乳/吮乳时长（nursing/suckling bout）逐渐缩短，母方发起的哺乳行为占比逐步降低，而母方主动终止哺乳/吮乳的频次不断升高。本研究确定幼崽7至13周龄为母犬与幼崽间的冲突窗口期：在此之后，幼崽的吮乳请求便会停止；而在此之前，母犬的拒哺行为较为少见。本研究还首次报道了幼崽利用犬类混交婚配制度下存在多头泌乳雌性的特点实施的盗奶行为（milk theft）。尽管该行为看似对母犬不利，但在高死亡率与资源竞争的选择压力下，或许对犬类种群具有适应性进化意义。