Science 6 September 2013: Vol. 341 no. 6150 p. 1055 DOI: 10.1126/science.341.6150.1055
News & AnalysisPlant Biology
Evolution Heresy? Epigenetics Underlies Heritable Plant Traits by Elizabeth Pennisi
Summary: “For some evolutionary biologists, just hearing the term epigenetics raises hackles. They balk at suggestions that something other than changes in DNA sequences, such as the chemical addition of methyl groups to DNA or other so-called epigenetic modifications, has a role in evolution. Yet a provocative study presented at an evolutionary biology meeting last month found that heritable changes in plant flowering time and other traits were the result of epigenetics alone, unaided by any sequence changes.”
Article excerpt: “At the meeting, he described how he and colleagues tied DNA methylation patterns to heritable variation in flowering time and root length in different strains of the model plant Arabidopsis thaliana.”
My comment: It is literally a “no-brainer” that plant reproduction is nutrient-dependent, as reproduction also is in all species of animals. If there is not a model of plant species diversification that attributes it to mutation-driven evolution, how can the molecular mechanisms of plant species diversification be extended to animal species diversification without chemical signals from plants that in animals are called species-specific pheromones?
Now that my first comment has been posted, I have submitted another comment to the Science site. Kudos to Abhay Sharma for encouraging more discussion:
My second comment: Note, we may have been the first to address molecular epigenetics in the context of hormone-organized and hormone-activated behavior. See: From Fertilization to Adult Sexual Behavior. Hormones and Behavior. 30 (4) 333-53.
Abhay Sharma now includes references to recent works that support cohesive thoughts on a new (old) approach to incorporating biological information into scientifically unsubstantiated theories about mutation-driven evolution, which has failed to incorporate the physiology of reproduction.
I will add a reference to my work that may help with integration of current information into a model of adaptive evolution based on biological facts that include the physiology of reproduction.
Nutrient-dependent/pheromone-controlled adaptive evolution: a model. Socioaffective Neuroscience & Psychology 2013, 3: 20553
The extension of our 1996 mammalian model to insects in 2000 and to their epigenetically-controlled life-stages in 2005 could have been expected to bring forward aspects of epigenetic effects on alternative splicings that are still somewhat in the background, but ever-present in the literature on precisely how the epigenetic “landscape” becomes the physical landscape of DNA in the organized genomes of species from microbes to man. That’s why I think that the molecular mechanisms, which enable the epigenetic effects, are the same in plants.
Does anyone think the molecular mechanisms are different enough to allow for the mutation-driven evolution of any extant or extinct species?