End the Hype over Epigenetics & Lamarckian Evolution
by Alex B. Berezow March 31, 2014
Excerpt: “Unlike regular genetics, which studies changes in the sequence of the DNA letters (A, T, C, and G) that make up our genes, epigenetics examines small chemical tags placed on those letters. Environmental factors play an enormous role in determining where and when the tags are placed. This is a big deal because these chemical tags help determine whether or not a gene is turned “on” or “off.” In other words, the environment can influence the presence of epigenetic tags, which in turn can influence gene expression.”
My comment:
Biophysical constraints on ecological adaptations, which are epigenetically linked to ecological variation (i.e., the environment) in species from microbes to man, are detailed in Genes without prominence: a reappraisal of the foundations of biology. The connections from physics and chemistry to the conserved molecular mechanisms of biologically-based ecological adaptations are discussed here: A Challenge to the Supremacy of DNA as the Genetic Material.
The connections from physics, chemistry, and molecular epigenetics to morphological and behavioral phenotypes are eliminated here: End the Hype over Epigenetics & Lamarckian Evolution. Hope is expressed that “… the concept of Lamarckian evolution may once again return to the grave.” What’s left will be the idea of constraint-breaking mutations and claims such as this one: We are all mutants: “… it’s his natural selection-busting theory, which Nei developed in the ’80s and expanded on in the 2013 book Mutation-Driven Evolution, that the researcher wants to see embraced, cited and taught in schools.”
Given the amount of hype associated with teaching mutation-initiated natural selection in schools, teaching mutation-driven evolution, which supposedly somehow occurs via constraint-breaking mutations, is virtually guaranteed to end any “hype” associated with teaching physics, chemistry and the biological basis of behavior. No changes are required to what’s currently being taught — if what’s being taught is that mutation-driven evolution “just happens.”
Hype that and you, too, can help end the hype over what has been known since 1996 about:
Molecular Epigenetics (in the section from our Hormones and Behavior review: From Fertilization to Adult Sexual Behavior)
Yet another kind of epigenetic imprinting occurs in species as diverse as yeast, Drosophila, mice, and humans and is based upon small DNA-binding proteins called “chromo domain” proteins, e.g., polycomb. These proteins affect chromatin structure, often in telomeric regions, and thereby affect transcription and silencing of various genes (Saunders, Chue, Goebl, Craig, Clark, Powers, Eissenberg, Elgin, Rothfield, and Earnshaw, 1993; Singh, Miller, Pearce, Kothary, Burton, Paro, James, and Gaunt, 1991; Trofatter, Long, Murrell, Stotler, Gusella, and Buckler, 1995). Small intranuclear proteins also participate in generating alternative splicing techniques of pre-mRNA and, by this mechanism, contribute to sexual differentiation in at least two species, Drosophila melanogaster and Caenorhabditis elegans (Adler and Hajduk, 1994; de Bono, Zarkower, and Hodgkin, 1995; Ge, Zuo, and Manley, 1991; Green, 1991; Parkhurst and Meneely, 1994; Wilkins, 1995; Wolfner, 1988). That similar proteins perform functions in humans suggests the possibility that some human sex differences may arise from alternative splicings of otherwise identical genes.”
If you try to hype what is known about molecular epigenetic, you will first need to learn about physics, chemistry, and the molecular biology of alternative splicings. See, for example: Alternative RNA Splicing in Evolution
