Neurogenic niche construction: our brain’s beginning?
October 16, 2013 | James Kohl
Excerpt: “…in an earlier study, Strausfeld’s team buried marine worms in mud and put them under high pressure to simulate the start of fossilisation—and their nerves lasted while their muscles decayed.”
My comment: Thanks. This seems to link neurogenic niche construction in nematodes to the prerequisite ecological and social niche construction, which are obviously nutrient-dependent and pheromone-controlled as is the socio-cognitive niche construction of insects and mammals. That eliminates mutation-initiated natural selection during half a billion years via evidence that the transition from grazing to predation in nematodes is nutrient-dependent and pheromone-controlled. For example, morphogenesis of teeth is nutrient-dependent, and the physiology of reproduction is pheromone-controlled.
Excerpts below from: “Nutrient-dependent/pheromone-controlled adaptive evolution: a model”
“Clearly, however, the epigenetic effects of food odors and pheromones are involved in neurogenic niche construction as exemplified in nematodes (Bumbarger, Riebesell, Rödelsperger, & Sommer, 2013), and in flies (Swarup et al., 2013).”
“Differences in the behavior of nematodes are determined by nutrient-dependent rewiring of their primitive nervous system (Bumbarger et al., 2013). Species incompatibilities in nematodes are associated with cysteine-to-alanine substitutions (Wilson et al., 2011), which may alter nutrient-dependent pheromone production.”
Summary: These nutrient-dependent changes appear to have enabled 500 species of stickleback fish to adaptively evolve during 15,000 years. What took other species so long? In theory, they had to wait for mutation-initiated changes and natural selection, but there’s no experimental evidence for that. Experimental evidence shows that changes in species are epigenetically controlled by nutrients and their metabolism to species-specific pheromones.