Human Ecology of Reproduction in Nomadic Turkana Pastoralists

在这个项目中，莱斯利博士和他的同事们将对居住在肯尼亚北部沙漠地区的图尔卡纳牧民进行生物学研究。这项研究的目标是了解图尔卡纳的生育能力，该团队将进行多项协调研究。通过月经日记和唾液孕酮测定，将有可能确定女性是否以及何时有生育能力，确定个人周期长度以及成年女性人口中有生育能力的比例。为了了解观察到的模式的原因，还将进行一些辅助研究。将收集关于健康和营养状况的数据，并将确定这些数据在一年中如何变化。将进行测量以确定身体成分和活动模式，并观察能量消耗。由于母乳喂养和生育率之间已经建立了联系，因此也将研究母乳喂养模式。从人口统计学的角度来看，图尔卡纳人是一个非常有趣的群体。他们是牧民，依靠他们的骆驼、奶牛、山羊和绵羊群作为食物。它们生活在恶劣的沙漠环境中，只有在一年中的特定时间才能获得有限的雨量。因此，它们在某些季节承受着严重的压力，而在其他季节则承受着较轻的压力。以前的研究表明，他们的能量摄入量很低。然而(可能是因为蛋白质摄入量过高)，平均生育水平非常高。此外，它还具有极强的季节性。这项研究的目的是进一步记录这一点并确定原因。这项研究之所以重要，有几个原因。它应该提供对控制生育的自然过程的更多了解。其次，尽管图尔卡纳人生活在压力很大的沙漠环境中，但他们已经非常好地适应了这种环境。在非洲其他环境相似的地区，当干旱来袭时，除非国际社会提供食物，否则人们会挨饿。美国政府为此花费了大量资金。希望关于图尔卡纳适应的知识能够在非洲其他地方发挥有用的作用。

In this project Dr. Leslie and his colleagues will conduct a biological study of Turkana pastoralists who live in the northern desert region of Kenya. The goal of the research is to understand Turkana fertility and the team will conduct a number of coordinated studies. Through menstrual diaries and salivary progesterone assay it will be possible to determine if and when women are fertile, determine individual cycle length and what percentage of the adult female population is fertile. To understand the causes of observed patterns a number of ancillary studies will also be carried out. Data will be collected on health and nutritional status and it will be determined how these vary over the course of the year. Measurement will be taken to determine body composition and activity patterns and energy expenditure will be observed. Since ties have been established between breast-feeding and fertility, breast-feeding patterns will also be studied. The Turkana are an extremely interesting population from a demographic perspective. They are pastoralists who depend on their herds of camels, cows, goats and sheep for food. They live in a harsh desert environment which receives limited amounts of rain only at specific times of the year. Therefore they are subjected to severe stress during some seasons and milder stress during others. Previous work has shown that their energy intake is low. However (perhaps because of high protein intake) the average fertility level is extremely high. Also it is extremely seasonal. The purpose of this study is to document this further and determine the causes. This research is important for several reasons. It should provide additional understanding of the natural processes which control fertility. Secondly, although the Turkana live in a highly stressful desert environment, they have adapted to it extremely well. In other environmentally similar areas of Africa, when drought strikes, people starve unless the international community provides food. The U.S. government expends large sums for this purpose. Hopefully what is learned about Turkana adaptation can serve a useful function elsewhere in Africa.