Moroccan Primate Conservation Foundation, Azrou, Morocco.
School of Psychology, University of Lincoln, Lincoln, United Kingdom.
Sci Rep. 2018 Apr 17;8(1):6074. doi: 10.1038/s41598-018-24373-4.
Individuals with more or stronger social bonds experience enhanced survival and reproduction in various species, though the mechanisms mediating these effects are unclear. Social thermoregulation is a common behaviour across many species which reduces cold stress exposure, body heat loss, and homeostatic energy costs, allowing greater energetic investment in growth, reproduction, and survival, with larger aggregations providing greater benefits. If more social individuals form larger thermoregulation aggregations due to having more potential partners, this would provide a direct link between sociality and fitness. We conducted the first test of this hypothesis by studying social relationships and winter sleeping huddles in wild Barbary macaques (Macaca sylvanus), wherein individuals with more social partners experience greater probability of winter survival. Precipitation and low temperature increased huddle sizes, supporting previous research that huddle size influences thermoregulation and energetics. Huddling relationships were predicted by social (grooming) relationships. Individuals with more social partners therefore formed larger huddles, suggesting reduced energy expenditure and exposure to environmental stressors than less social individuals, potentially explaining how sociality affects survival in this population. This is the first evidence that social thermoregulation may be a direct proximate mechanism by which increased sociality enhances fitness, which may be widely applicable across taxa.
个体拥有更多或更强的社会联系，在各种物种中都能提高生存和繁殖能力，尽管介导这些影响的机制尚不清楚。社会体温调节是许多物种共有的一种行为，它可以减少寒冷压力的暴露、身体热量的损失和体内平衡的能量消耗，从而允许在生长、繁殖和生存方面进行更大的能量投资，更大的聚集提供更大的好处。如果更多的社会性个体由于有更多的潜在伴侣而形成更大的体温调节聚集，那么这将在社会性和适应性之间提供直接联系。我们通过研究野生巴巴里猕猴（Macaca sylvanus）的社会关系和冬季睡眠群集，首次检验了这一假设，在这种情况下，拥有更多社会伴侣的个体更有可能在冬季存活。降水和低温增加了集群的规模，支持了之前的研究，即集群的规模会影响体温调节和能量学。集群关系由社会（梳理）关系预测。因此，拥有更多社会伴侣的个体形成了更大的集群，这表明它们的能量消耗和对环境压力源的暴露减少，这可能解释了社会性如何影响该种群的生存。这是第一个证据表明，社会体温调节可能是增加社会性提高适应性的直接近因机制，这在广泛的分类群中可能是普遍适用的。
