OLDEST OLD MORTALITY IN NATURE--BIODEMOGRAPHIC ANALYSES

最近由NIA支持的实验工作表明，可能存在一个 最年长年龄的死亡竞赛减速。这种减速具有 在人类、苍蝇、果蝇和线虫四个物种中被发现， 然而，这些人口统计模式的广度尚不清楚。主要目标是 这项研究的建议将是确定死亡率减速是否 最古老的是在自然界的种群中发现的。生物人口学研究 到目前为止，老化都使用了实验室条件。这将是第一次 比较自然和自然条件下物种的人口学特征的研究 实验室条件。这个项目将测试年龄的遗传基础-- 特定死亡率，以确定是否和多少 不同的基因类型的死亡轨迹和寿命不同 自然种群。它还将检验当前的一个主要假设 衰老的进化论，即年龄选择的力量- 比存活率和繁殖力随着年龄的增长而下降。原因字段 用动物做实验很困难，这项研究将使用植物物种 在自然环境中，确定衰老和死亡率 减速发生在自然种群中。这是一个试验性项目 是一个更大的研究计划的第一步，将提交 作为美国国家航空航天局资助的项目的补充，该项目名为 死亡率--人口模型和分析“(Pol AGO876I，James Vaupel， 首席调查员)。

Recent experimental work supported by NIA, suggests that there may be a deceleration of mortality races at the oldest ages. This deceleration has been found in four species, humans, medflies, Drosophila, and nematodes, yet the breadth of these demographic patterns is not known. The major aim of this research proposal will be to determine if mortality deceleration of the oldest-old is found in populations in nature. Biodemographic studies of aging up until now have used laboratory conditions. This will be the first study to compare the demography of a species under both natural and laboratory conditions. This project will test the genetic basis of age- specific mortality rates in order to determine whether and how much genotypes differ in their mortality trajectories and lifespans within natural populations. It will also test a major assumption of the current evolutionary theories of senescence, that the strength of selection on age- specific survival and fecundity declines with age. Because field experiments with animals are difficult, this study will use plant species in a natural environment, to determine whether senescence and mortality deceleration occur in natural populations. This is a pilot project designed to be the first step in a larger research program which will be submitted as a supplement to the NIA-funded Program Project entitled "Oldest-old mortality - Demographic models and analysis" (POl AGO876I, James Vaupel, Principal Investigator).