by Ed Yong
Excerpt: “This is a landmark study of collective behaviour,” says Iain Couzin… “Never before has it been possible to unweave the intricate coding of social behaviour during collective decision-making.” When it comes to fruit flies, scientists… can really start to understand the origins of collective behaviour—how genes in the fly’s neurons are activated, how those neurons process signals from the fly’s environment, and how they drive individual behaviours that, in turn, lead to swarm behaviour. This is the future of the field, and one that I hinted at in my piece for Wired.”
My comment: This is also the basis for what I was taught to believe was required. See for example: Understanding the bases of sex differences, “The articles in this issue summarize the factors surrounding sex differences with respect to ontogeny, phenotype, and hormone-sensitive actions. They follow a sequence that begins with genetic sex differences and carries through to cell, tissue, organ and, finally, systemic effects of gender.
Simply put, I was taught that any model of cell type differentiation must start with gene activation. I’ve since wondered how anyone else could be taught to believe that mutations link natural selection or anything else to the evolution of increasing organismal complexity manifested in biodiversity. Others now know that my mentors were correct. See, for example: Mechanosensory interactions drive collective behaviour in Drosophila
Excerpt: “Through Encounter Responses, odour reactions of sensitive flies spark cascades of directed locomotion of less sensitive (or even insensitive) individuals, causing a coherent departure from the odour zone. This behavioural positive feedback and group motion are absent among flies in the non-odour zone since they are less likely to initiate walking and, consequently, have a reduced frequency of Encounters. Additionally, flies retreat when encountering the odourwhile transiting from the air zone. Together these behavioural phenomena cause flies to escape the odour zone and then remain in the air zone, resulting in higher odour avoidance for groups compared to isolated animals (Extended Data Fig. 6).
My comment: A series of published works that link odor-induced gene activation exemplified in the context of c-fos and Fos gene expression in gonadotropin releasing hormone (GnRH) secreting neurons in the GnRH neuronal system of rats supported the claims I presented in 1992 as “Luteinizing Hormone: The link between sex and the sense of smell?”
My claims were based, in part, on “The universality of the GnRH-induced behavioral response in the nonhuman species (from lizard to monkey) and the endocrine-pituitary actions of GnRH in pituitary secretion of LH and FSH, couples with the possible relationship between human sexual behavior deficits and gonadotropin dysfunction, provided good justification to proceed with further investigation into the behavioral effects of GnRH on human sexual behavior.” — see: Gonadotropin releasing hormone and human sexual behavior (p. 61)
Excerpt: “The five-step logical pathway that directly links sensory input from the social environment to the development of sexual preferences and sexual behavior is gene→cell→tissue→organ→organ system. Failure to incorporate any of the steps in this pathway makes it impossible to directly connect to sexual preferences and sexual behavior, a logical sequence of events that must somehow and somewhere begin with the effect of sensory input from the social environment. For example, activation of tissue in and of itself does not detail what genes and in what cells of the tissue are activated by the sensory input from the social environment.”
Activation of motor movements clearly is conditioned to occur in the context of olfactory/pheromonal input. No experimental evidence of biologically-based cause and effect links sight, touch, hearing, or taste to movement in organisms from microbes to man. Responses to other sensory input always occur in the context of food odors or pheromones. It is ridiculous to claim that the responses of all species are not conditioned via gene activation that begins with the experience-dependent induction of olfactory receptor genes in mosquitoes, all other invertebrates, and all vertebrates based on what is currently known about the de novo creation of olfactory receptor genes compared to mutations that perturb protein structure and function.
Nothing infers that proteins evolved. Amino acid substitutions are nutrient-dependent and are readily distinquished from mutations that perturb protein folding.
Excerpt: “We cannot conceive of a global external factor that could cause, during this time, parallel evolution of amino acid compositions of proteins in 15 diverse taxa that represent all three domains of life and span a wide range of lifestyles and environments. Thus, currently, the most plausible hypothesis is that we are observing a universal, intrinsic trend that emerged before the last universal common ancestor of all extant organisms.”
The universal trend links metabolic networks to genetic networks via nutrient-dependent RNA-mediated events without the pseudoscientific nonsense about mutations and evolution.