The reliability theory of aging is an attempt to apply the principles of reliability theory to human biology. The theory was published in Russian by Leonid A. Gavrilov and Natalia S. Gavrilova as Biologiia prodolzhitelʹnosti zhizni in 1986, and in English translation as The Biology of Life Span: A Quantitative Approach in 1991.
The hypothesis is based on the premise that humans are born in a highly defective state. According to the model, this is then made worse by environmental and mutational damage; redundancy allows the organism to survive for a while.
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Reliability theory of aging and longevity Wikipedia(Text) CC BY-SA