Doctoral Dissertation Research: Aging, frailty, and foraging ability in wild male primates

虽然长寿通常被描述为人类独有的特征，但黑猩猩等其他类人猿的寿命也很长，是猴子或狐猴的两倍。然而，我们并不完全了解衰老对野生猿类的影响，也不完全了解人类长寿的哪些方面是独一无二的。这个博士研究项目将调查野生雄性黑猩猩在生理和行为上是如何衰老的，重点是衰老如何影响觅食能力，这可能会揭示脆弱是如何影响健康的。这一发现将有助于弄清黑猩猩的进食行为和表现是否会随着年龄的增长而改变，以及觅食是否会在形成它们的衰老模式中发挥重要作用。这项研究将填补我们在雄性灵长类动物骨骼生物学衰老方面的知识空白，并可能有助于澄清在生命后期保持生育能力是否有助于延长寿命的进化。这些研究人员将在美国和乌干达农村的研究地点附近从事教育活动，并促进国际研究合作和能力建设。此外，研究人员在基巴莱国家公园的持续存在有助于保护整个东非最后的热带雨林之一，这是该地区黑猩猩的主要据点之一。这项拟议中的研究将调查生活在乌干达基巴莱国家公园Ngogo一个超大社区的雄性黑猩猩的衰老情况。研究人员将评估不同年龄的成年雄性黑猩猩的生理特征，以评估骨密度、体重、咀嚼能力和精力状态如何在老年时下降。为此，该研究将非侵入性地收集和分析粪便样本以评估咀嚼效率，以及尿液样本以测量胰岛素生物标志物（能量状态的指标）和胶原蛋白生物标志物以研究骨密度的降低。还将进行行为观察，以评估这些生理变化如何影响运动、食物选择、摄食率、交配努力和社交。本研究通过对雄性黑猩猩衰老生理和行为的系统研究，旨在阐明野生动物衰老过程及其对健康的影响。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

While longevity is often described as a uniquely human trait, other apes like chimpanzees also have extended lifespans, living twice as long as monkeys or lemurs. However, we don't fully understand the effects of aging on apes in the wild or which aspects of human longevity are unique. This doctoral research project will investigate how wild male chimpanzees age physiologically and behaviorally with a focus on how aging impacts foraging ability, which may reveal how frailty impacts fitness. The findings will help clarify whether chimpanzees' feeding behavior and performance change with age, and whether foraging could play an important role in shaping their patterns of senescence. This research will fill gaps in our knowledge on the senescence of male primate skeletal biology and may help to clarify whether fertility maintained late in life contributes to the evolution of extended lifespan. The investigators will engage in educational activities in the United States and near the research site in rural Uganda, and foster international research collaborations and capacity building. In addition, the continued presence of researchers in Kibale National Park helps protect one of the last tropical rainforests in all of East Africa, which is notably one of the principal strongholds of chimpanzees in this area.The proposed research will investigate aging in male chimpanzees living in an exceptionally large community at Ngogo, Kibale National Park, Uganda. The investigators will assess the physiological traits of adult male chimpanzees at various ages to assess how bone density, body mass, chewing ability, and energetic status may decrease in old age. To this end, the research will non-invasively collect and analyze fecal samples to assess chewing efficiency as well as urine samples to measure insulin biomarkers (an indicator of energetic status) and collagen biomarkers to investigate decreases in bone density. Behavioral observations will also be carried out to assess how these physical changes may impact movement, food selection, ingestion rates, mating effort, and sociality. Through a systematic study of aging male chimpanzees' physiology and behavior, this research aims to elucidate the processes of aging and its impact on fitness in wild animals.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.