Historical (Life History) Hypothesis

Type: Non adaptive hypothesis

Definition: The major determinant of life tables is the ancestry of each phylum or sub-phylum or group of species, i.e. the phylogenetic history of each species, and selective factors have importance only in modulating these ancestral patterns.

Proposers: De Magalhães & Toussaint 2002.

Empirical Evidence:
1) The existence of animals with negligible senescence is compatible with the hypothesis
2) The inverse correlation observed in the wild between extrinsic mortality rate and proportion of deaths due to intrinsic mortality is not predicted by the hypothesis
3) The existence of mechanisms genetically determined and regulated limiting cell turnover and, therefore, lifespan is against the hypothesis

Conclusion: Historical hypothesis does not appear a plausible explanation of aging and some empirical data are against it. However, it should be carefully considered as an inertial factor that limits the transformations from a life table pattern to another.

References:
- De Magalhães, J.P. & Toussaint, O. (2002) The evolution of mammalian aging. Exp. Gerontol. 37, 769-75.
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