Byun Catherine A, Lutz Meredith C, Lewis Rebecca J
Department of Anthropology, University of Texas at Austin, Austin, Texas, USA.
Animal Behavior Graduate Group, University of California, Davis, California, USA.
Am J Primatol. 2025 Jun;87(6):e70057. doi: 10.1002/ajp.70057.
The immature period is an essential time of physical and behavioral development in which individuals prepare to navigate their environment as adults. Activity budgets provide valuable insight into the tradeoffs individuals make based on their energetic priorities. We hypothesized that energetic priorities differ across the stages of development based on the distinct social and ecological needs of that stage. We analyzed 31,113.5 h of focal instantaneous sampling data from 2007 to 2024 on 73 Verreaux's sifaka (Propithecus verreauxi) living in Kirindy Mitea National Park, Madagascar to investigate the effects of age class, sex, and seasonality on activity budgets. Juveniles and subadults devoted significantly more time to social activity than adults. Subadults fed less than other age classes, and we detected no differences in resting among age classes. Among all age classes, males devoted more time to social activity than females, and all age classes displayed sex differences in additional activities. All age-sex classes exhibited similar seasonal patterns in activity budgets. Our results indicate that social activity may be especially important in the developmental period to gain experience and establish social relationships before adulthood. Sex differences in social activity appear to emerge earlier than adulthood as a predisposition for the reproductive roles of adulthood. Overall, we found that energetic priorities differ between stages of development, and evidence is mixed regarding whether these differences are primarily due to the onset of reproduction.
未成熟期是身体和行为发展的关键时期，在此期间个体为成年后在其环境中生存做准备。活动预算能让我们深入了解个体根据其能量优先级所做出的权衡。我们假设，基于该阶段独特的社会和生态需求，能量优先级在发育阶段会有所不同。我们分析了2007年至2024年对生活在马达加斯加基林迪米泰亚国家公园的73只维氏冕狐猴（Propithecus verreauxi）进行的31113.5小时的焦点瞬时抽样数据，以研究年龄组、性别和季节性对活动预算的影响。幼年和亚成年个体用于社交活动的时间显著多于成年个体。亚成年个体进食时间少于其他年龄组，且我们未发现各年龄组在休息时间上存在差异。在所有年龄组中，雄性用于社交活动的时间多于雌性，且所有年龄组在其他活动方面也存在性别差异。所有年龄 - 性别组在活动预算方面都呈现出相似的季节性模式。我们的结果表明，社交活动在发育时期可能尤为重要，以便在成年前积累经验并建立社会关系。社交活动中的性别差异似乎在成年之前就已出现，这是成年后生殖角色的一种倾向。总体而言，我们发现能量优先级在发育阶段有所不同，而关于这些差异是否主要归因于繁殖的开始，证据并不一致。
