A model for ageing

Abstract

The model takes into account two main characteristics of ageing: (1) deterioration of adaptability of an organism to environment after maturity and (2) determination of life span of a species. The essential features of the model are that (a) differentiation, growth, maturity and senescence occur in this order, and each of these phases has its own characteristic, duration and speed in a species; this linear order occurs due to sequential activation and repression of genes, and (b) addition or deletion or any other changes of one or more genes in this sequence resulting in the origin of a new species may also accelerate or decelerate the sequence in the new species, and thus decrease or increase its life span.