Dynamics of mortality in protected populations

Abstract

Demographic data and recent experiments verify earlier predictions that mortality has short (few percent of the life span) memory of the previous life history, may be significantly decreased, reset to its value at a much younger age, and (until certain age) eliminated. Such mortality dynamics is demonstrated to be characteristic only of evolutionary unprecedented protected populations. When conditions improve, their mortality decreases stepwise. At crossovers the rate of decrease rapidly changes. The crossovers manifest the edges of the stairs in the universal ladder of rapid mortality adjustment to changing conditions. Mortality is dominated by the established universal law which reduces it to few biologically explicit parameters and which is verified with human and fly mortality data. Specific experiments to test universality of the law for other animals, and to unravel the mechanism of stepwise life extension, are suggested.