OLDEST OLD MORTALITY IN NATURE--BIODEMOGRAPHIC ANALYSES

最近由NIA支持的实验工作表明， 在最老年龄的死亡率下降。这种减速 在四个物种中发现，人类，地中海果蝇，果蝇和线虫， 然而，这些人口模式的广度尚不清楚。主要目标 这项研究的目的是确定死亡率的降低是否 最古老的存在于自然界的种群中。生物人口学研究 老化到现在为止都使用实验室条件。这将是第一 一项研究，比较一个物种在自然和 实验室条件这个项目将测试年龄的遗传基础- 具体的死亡率，以确定是否和多少 基因型的死亡轨迹和寿命不同， 自然人口。它还将测试当前的一个主要假设， 衰老的进化理论，即年龄选择的强度- 特定存活率和繁殖力随年龄而下降。因为菲尔德 动物实验很困难，这项研究将使用植物物种 在自然环境中，以确定是否衰老和死亡 减速发生在自然种群中。这是一个试点项目， 作为一个更大的研究计划的第一步， 作为对国家免疫局资助的题为“最年长的老人”的方案项目的补充， 死亡率-人口模型和分析”（PO 1AGO 876 I，JamesVaupel， 首席研究员）。

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).