Time between birth and death. It ranges from a mayfly's day to certain trees' thousands of years. Its limit appears to depend on heredity, but such factors as (in humans) disease, natural disasters, war, diet, and habits such as smoking reduce it. Maximum life span is theoretical; more meaningful is average life span, which life-insurance companies and actuaries analyze and tabulate. Long-lived progenitors tend to beget long-lived descendants. A very-low-calorie diet appears to prolong life. Reduced infant mortality and improved sanitation and nutrition account for much of the increase since circa 1800—from about 35 to over 70 years in most industrialized countries. The oldest well-documented age reached by a human is 122 years.
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Extension of Life-Span by Loss of CHICO, a Drosophila Insulin Receptor Substrate Protein.(gene mutation research)(Brief Article)
Apr 06, 2001; Mutations that extend life-span illuminate the molecular mechanisms underlying aging and longevity. In Caenorhabditis elegans,...
The Genetic Architecture of Life Span and Mortality Rates: Gender and Species Differences in Inbreeding Load of Two Seed-Feeding Beetles
Oct 01, 2006; ABSTRACT We examine the inbreeding load for adult life span and mortality rates of two seed beetle species, Callosobruchus...