Wang et al (2013) make it clearer that epigenetic modifications of genes found in social chromosomes entered continuum of adaptive evolution before the sex chromosomes.
“… the “mutational vicinity” is probably found in the molecular vicinity of a “metabolic niche”.
I think what they’ve just shown us exemplifies the molecular biology of epigenetically driven adaptive evolution.
The epigenetic effects of nutrient chemicals on gene duplication and species diversity and the ability to metabolize nutrient chemicals is controlled by the metabolism of the nutrient chemicals to pheromones that epigenetically control reproduction in all species
The only explanation for adaptive evolution with any across species explanatory power is found in my details of the epigenetic effects of olfactory/pheromonal input on intracellular signaling and stochastic gene expression…
Integrating the chemical ecology of the social brain’s adaptive evolution allows it to be viewed – along with adaptive evolution of the CNS – at four levels of niche construction: 1) ecological, 2) social, 3) neurogenic, and 4) socio-cognitive.
No neurogenic niche does not mean no behavior, and no socio-cognitive niche only means that the unconscious affects of sensory stimuli on hormones and behavior will predominate.