Article,
Evolvability Suppression to Stabilize Far-Sighted Adaptations
Artificial Life, (2004)In press.
Abstract
The opportunistic character of adaptation through
natural selection can lead to `evolutionary
pathologies'---situations in which traits evolve that
promote the extinction of the population. Such
pathologies include imprudent predation and other forms
of habitat over-exploitation or the `tragedy of the
commons', adaptation to temporally unreliable
resources, cheating and other antisocial behaviour,
infectious pathogen carrier states, parthenogenesis,
and cancer, an intra-organismal evolutionary pathology.
It is known that hierarchical population dynamics can
protect a population from invasion by pathological
genes. Can it also alter the genotype so as to prevent
the generation of such genes in the first place, i.e.
suppress the evolvability of evolutionary pathologies?
A model is constructed in which one locus controls the
expression of the pathological trait, and a series of
modifier loci exist which can prevent the expression of
this trait. It is found that multiple `evolvability
checkpoint' genes can evolve to prevent the generation
of variants that cause evolutionary pathologies. The
consequences of this finding are discussed.
