Excerpt 1): “…new neuronal types and connections are often not taken into account in building a model of the olfactory bulb network. We are concerned with this trend of omission as it may hinder future progress in research.”
My comment: I share their concerns. The omission of what is currently known about RNA-mediated cell type differentiation, which occurs via nutrient-dependent amino acid substitutions, extends across disciplines. The omission consistently leads some serious scientists to report their experimental evidence of biologically-based cause and effect as if mutations and natural selection somehow led to neuronal organization of olfactory bulb circuits. They ignore the requirements for epigenetically-effected ecological, social, neurogenic, and socio-cognitive niche construction manifested in the morphological and behavioral phenotypes of species from microbes to man, and attribute changes to mutations, natural selection, and the evolution of biodiversity.
I have focused on detailing all aspects of how odors regulate behavior for more than 30 years and incorporated what is currently know into a model of cell type differentiation across species via conserved molecular mechanisms. I included citations to others whose works clearly link the sensory environment to behavior via conserved molecular mechanisms in a 2012 review that concluded: “Olfaction and odor receptors provide a clear evolutionary trail that can be followed from unicellular organisms to insects to humans…”
The conclusion of my 2013 review clearly stated:
“… ‘our experiments suggest that excitatory odor responses are transiently suppressed (in terms of overall firing rates), but more complex temporal shaping of responses may occur because of interplay of intrinsic properties, sensory drive, and the feedback activity’ (Markopoulos, Rokni, Gire, & Murthy, 2012, p. 1186). In context, this was suggested in ‘Feedback loops link odor and pheromone signaling with reproduction’ (Boehm, Zou, & Buck, 2005).
If this genes-to-behavior-and-back model of systems biology is correct, it shows what has gone missing from cause and effect in the context of adaptive evolution of the human brain and behavior. What is missing is the complex interplay of intrinsic properties, sensory drive, and the feedback activity, which requires the acknowledgement that mammalian pheromones, including human pheromones, obviously exist. That fact should be as obvious as the fact that the ecological epigenetics of food odors exist.”
Excerpt 2): Ultimately, as we dissect and begin to understand the detailed nature of the olfactory circuit networks, our next questions must focus on understanding how odorants within these circuits play a role in regulating behavior.
That statement attests to the ignorance of detailed biologically-based cause and effect. It is one of the most pertinent examples of how others proceed with claims that there remains a need for understanding what has already been explained. The explanation includes the fact that “Olfaction and odor receptors provide a clear evolutionary trail that can be followed from unicellular organisms to insects to humans…”. What is it that’s not understood about the fact that odor-induced de novo Creation of odor receptors regulates behavior? If it is merely the use of Creation in an explanation of biologically-based cause and effect, evolutionary theorists should describe whatever evolutionary event they think links mutations and natural selection to the evolution of behavior, or accept the fact that behavior does not ‘evolve’ and move forward based on three facts known by serious scientists:
1) Ecological variation leads to ecological adaptations manifested in the morphological and behavioral phenotypes of species from microbes to man.
2) Species that failed to ecologically adapt did not mutate into any transitional life form naturally selected to evolve.
3) The lack of food or their inappropriate response to food odors and pheromones led to extinction, not to the evolution of increasing organismal complexity via conserved molecular mechanisms in species from microbes to man.