A detailed model explains how chemical ecology drives adaptive evolution via 1) ecological niche construction, 2) social niche construction, 3) neurogenic niche construction, and 4) socio-cognitive niche construction (Kohl, 2012). That model is used to exemplify the effects of olfactory /pheromonal conditioning, which alters genetically predisposed, nutrient chemical-dependent, hormone-driven mammalian behavior and choices for pheromones that control reproduction via their effects on luteinizing hormone (Kohl, 1992). For example, clink on the link below to view my poster presentation from November 9, 2012, which represents two decades of neuroscientific progress.
Human Pheromones: Epigenetic Effects of Odors and Their Affects on Behavior
As is indicated in the poster text: This model of systems biology represents the conservation of bottom-up organization and top-down activation via:
1. Nutrient-dependent stress-induced and social stress-induced intracellular changes in the homeostatic balance of microRNA(miRNA) and messenger RNA (mRNA);
2. Intermolecular changes in DNA (genes);
3. Non-random experience-dependent stochastic variations in de novo gene expression for odor receptors;
4. The required gene-cell-tissue-organ-organ system pathway that links sensory input directly to gene activation in neurosecretory cells of the brain;
5. The required reciprocity that links gene expression to behavior that alters gene expression (i.e., from genes to behavior and back).
Additional support for this model can be found in: Evolution of the human-specific microRNA miR-941, which is an open access article — published on
Across species comparisons of epigenetic effects on genetically predisposed nutrient-dependent and hormone-driven invertebrate and vertebrate social and sexual behavior indicate that human pheromones also alter the development of the brain and behavior via the same molecular mechanisms. Obviously, those molecular mechanisms must be conserved across all species for adaptive evolution of the human brain and human behavior to occur (e.g., via properly timed reproductive sexual behavior of mammals).
Note: In mammals, LH secretion is the measurable proxy for genetically predisposed differences in hypothalamic GnRH pulse frequency and amplitude and the downstream effects of GnRH on the HPG and HPA axes that provide feedback to the GnRH neuronal system, which is the central regulator of genetically predisposed nutrient chemical-dependent individual survival and pheromone-dependent species survival.
James V. Kohl detailedl how quantized energy-dependent microRNA biogenesis links the pheromone-controlled physiology of reproduction to biophysically constrained viral latency and healthy longevity. Links from what organisms eat to the enzyme-dependent metabolism of food also link metabolic networks to microRNA-mediated genetic networks in the context of RNA interference. Drug therapies alter RNA interference by altering cell type differentiation in all cells of all individuals of all species. For comparison, during the past 26 years, Kohl has detailed how the chemistry of protein folding is biophysically constrained at every level of biological organization by conserved molecular mechanisms.