School of Biological and Chemical Sciences, Queen Mary University of London, UK.
Anim Cogn. 2011 Jul;14(4):585-98. doi: 10.1007/s10071-011-0396-3. Epub 2011 Apr 19.
Parent-offspring recognition can be essential for offspring survival and important to avoid misdirected parental care when progeny mingle in large social groups. In ungulates, offspring antipredator strategies (hiding vs. following) result in differences in mother-offspring interactions, and thus different selection pressures acting on the recognition process during the first weeks of life. Hider offspring are isolated and relatively stationary and silent to avoid detection by predators, whereas follower offspring are mobile and rapidly mix in large social groups. For these reasons, hiders have been suggested to show low offspring call individuality leading to unidirectional recognition of mothers by offspring and followers high offspring call individuality and mutual recognition. We hypothesised that similar differences would exist in hider species between the hiding phase (i.e. unidirectional recognition) and the phase when offspring join social groups (i.e. mutual recognition). We tested these predictions with goats (Capra hircus), a hider species characterised by strong mother-offspring attachment. We compared the individuality of kid and mother calls, and the vocal recognition ability, during the early phase of life when kids are usually hidden and later when kids have typically joined social groups. Contrary to our predictions, we found that both kids and mothers had individualised contact calls and that mutual recognition existed even during the hiding phase. The large differences in the duration of the hiding phase and in the rate of mother-offspring interactions (possibly partially driven by domestication in some species) probably cause variations among hider species in the mother-offspring recognition process.
亲代-后代识别对于后代的生存至关重要，并且在后代在大型社会群体中混合时，避免错误的亲代照顾也很重要。在有蹄类动物中，后代的捕食者防御策略（隐藏与跟随）导致了亲代-后代相互作用的差异，因此在生命的最初几周，识别过程会受到不同的选择压力的影响。躲藏的后代是孤立的，相对静止和安静的，以避免被捕食者发现，而跟随的后代则是移动的，并且在大型社会群体中迅速混合。由于这些原因，有人认为躲藏者的后代叫声个体性较低，导致后代单向识别母亲，而跟随者的后代叫声个体性较高，并且相互识别。我们假设在躲藏物种中，躲藏阶段（即单向识别）和后代加入社会群体的阶段（即相互识别）之间会存在类似的差异。我们使用山羊（Capra hircus）进行了这些预测，山羊是一种具有强烈母子依恋的躲藏物种。我们比较了幼崽和母亲叫声的个体性，以及在生命早期（幼崽通常躲藏）和后期（幼崽通常已经加入社会群体）的发声识别能力。与我们的预测相反，我们发现幼崽和母亲都有个性化的联系叫声，即使在躲藏阶段也存在相互识别。躲藏阶段的持续时间和母子互动的频率存在很大差异（可能部分是由某些物种的驯化驱动的），这可能导致躲藏物种在母子识别过程中存在差异。
