Individual differences in maternal behavior toward, and investment in, offspring can have lasting consequences, particularly among primate taxa characterized by prolonged periods of development over which mothers can exert substantial influence. Given the role of the neuroendocrine system in the expression of behavior, researchers are increasingly interested in understanding the hormonal correlates of maternal behavior. Here, we examined the relationship between maternal behavior and physiological stress levels, as quantified by fecal glucocorticoid metabolite (FGM) concentrations, in lactating chimpanzees, Pan troglodytes schweinfurthii, at Gombe National Park, Tanzania. After accounting for temporal variation in FGM concentrations, we found that mothers interacted socially (groomed and played) with and nursed their infants more on days when FGM concentrations were elevated compared to days when FGM concentrations were within the range expected given the time of year. However, the proportion of time mothers and infants spent in contact did not differ based on FGM concentrations. These results generally agree with the suggestion that elevated GC concentrations are related to maternal motivation and responsivity to infant cues and are the first evidence of a hormonal correlate of maternal behavior in a wild great ape.

中文翻译：

---

野生黑猩猩（Pan troglodytes schweinfurthii）的母性行为和生理压力水平


母亲对后代的行为和投资的个体差异可能会产生持久的影响，特别是在以长期发育为特征的灵长类动物中，母亲可以对其施加重大影响。鉴于神经内分泌系统在行为表达中的作用，研究人员越来越有兴趣了解母亲行为的激素相关性。在这里，我们研究了坦桑尼亚贡贝国家公园哺乳期黑猩猩 Pan troglodytes schweinfurthii 的母性行为与生理压力水平之间的关系，通过粪便糖皮质激素代谢物 (FGM) 浓度进行量化。在考虑了 FGM 浓度的时间变化后，我们发现，与 FGM 浓度在一年中的预期范围内的日子相比，在 FGM 浓度升高的日子里，母亲与婴儿的社交互动（梳洗和玩耍）和哺乳次数更多。然而，母亲和婴儿接触的时间比例并没有因女性生殖器切割浓度而异。这些结果总体上同意这样的建议，即GC浓度升高与母性动机和对婴儿线索的反应性有关，并且是野生类人猿母性行为与激素相关的第一个证据。