Non-senescence in Classical Evolutionary Theory

H. Saunders
Decision Processes Inc., USA

Traditional statements of the classical evolutionary theory of senescence claim that senescence is a virtually inevitable result of the fact that genes affecting survival or fecundity only early in life have a greater selective impact than genes that express only late in life.
However, it can easily be shown that the standard theory allows for non-senescent genotypes to dominate and displace senescent genotypes under a variety of conditions. This presentation will show quantitative modeling results demonstrating the dominance of non-senescent genotypes across specific domains of certain inputs used in standard theories, namely fecundity rates, mutation rates, and fidelity and accuracy of breeding.
The quantitative model, a dynamic systems model, adheres to exacting theoretical standards, depicting different genotypes within a population exhibiting different tradeoffs between intrinsic lifespan and fecundity, and permits the accumulation of mutations. The use of dynamic systems theory allows the extraction of system eigenvectors and eigenvalues that provide a clear picture of genotype structure and enables compact extensions of the classical Euler-Lotka equation and its derivatives. This methodology also provides insight into the field studies of Reznick et al. on predator-mitigated senescence in Trinidadian guppies, Poecilia Reticulata. It further generates predictions conforming to standard theory with respect to population fecundity trends with age, population mortality trends with age, Williams' Hypothesis, and the evolution of semelparity and iteroparity.
The significance of these results is that standard theory does not disallow the evolution of non-senescent populations.

Homo Sapiens Liberatus Workshop, Moscow State University, May 2010