Department of Anthropology and Archaeology, University of Calgary, Calgary, Alberta, Canada.
Department of Anthropology and Archaeology, University of Calgary, Calgary, Alberta, Canada; Department of Anthropology, McGill University, Montreal, Quebec, Canada.
Horm Behav. 2020 Feb;118:104632. doi: 10.1016/j.yhbeh.2019.104632. Epub 2019 Dec 13.
A key goal in behavioral ecology is to investigate the factors influencing the access to food resources and energetic condition of females, which are strong predictors of their reproductive success. We aimed to investigate how ecological factors, social factors, and reproductive state are associated with energetic condition in a wild neotropical primate using non-invasive measures. We first assessed and compared urinary C-peptide levels (uCP), the presence of urinary ketones (uKet), and behaviorally assessed energy balance (bEB) in female white-faced capuchin monkeys (Cebus imitator) living in Santa Rosa, Costa Rica. Then, we assessed how these measures were associated with feeding competition, dominance rank, and reproductive state. As predicted, uCP and bEB were positively associated with each other, and bEB was negatively associated with uKet. However, we did not find a relationship between uCP and uKet. Females showed lower uCP and bEB values during periods of intense feeding competition, but this relationship was not dependent on dominance rank. Furthermore, rank was not directly associated with uCP and bEB. Urinary ketones, on the other hand, were only produced in the most adverse conditions: by low-ranking, lactating females during periods of intense feeding competition. Behavioral strategies are assumed to maximize reproductive success and not energetic condition per se, which might explain why rank was not generally associated with energetic condition in our study population. This highlights the importance of considering potential differences between reproductive success and proxies of reproductive success, such as energetic condition or food intake, when investigating predictions of socioecological models.
行为生态学的一个主要目标是研究影响雌性获取食物资源和能量状况的因素，因为这些因素是雌性生殖成功的重要预测指标。我们旨在使用非侵入性测量方法研究生态因素、社会因素和生殖状态如何与野生新热带灵长类动物的能量状况相关联。我们首先评估和比较了生活在哥斯达黎加圣罗莎的白脸卷尾猴（Cebus imitator）的尿 C 肽水平（uCP）、尿酮体（uKet）的存在以及通过行为评估的能量平衡（bEB）。然后，我们评估了这些措施如何与觅食竞争、支配地位和生殖状态相关联。正如预测的那样，uCP 和 bEB 彼此之间呈正相关，bEB 与 uKet 呈负相关。然而，我们没有发现 uCP 和 uKet 之间存在关系。在激烈的觅食竞争期间，雌性的 uCP 和 bEB 值较低，但这种关系并不依赖于支配地位。此外，等级与 uCP 和 bEB 没有直接关系。另一方面，尿酮体仅在最不利的条件下产生：在激烈的觅食竞争期间，处于低等级的哺乳期雌性。行为策略被认为是最大限度地提高生殖成功，而不是能量状况本身，这可能解释了为什么在我们的研究群体中，等级通常与能量状况没有关联。这突出表明，在研究社会生态模型的预测时，考虑生殖成功和生殖成功的替代指标（如能量状况或食物摄入）之间的潜在差异非常重要。
