Re:Can Darwinian Evolution Explain Lamarckism?
by SamBam on Wednesday May 17, 2017 @12:39PM
(#14360156)
Epigenetic mechanisms are heritable. Just via other methods than DNA base-pair order. For example, through chromatin bookmarking, which effects the state of the DNA (which parts are tightly folded and which aren't), not the code itself:
https://en.wikipedia.org/wiki/Transgenerational_epigenetic_i...
Re:Can Darwinian Evolution Explain Lamarckism?
by biomcgary on Thursday May 11, 2017 @06:54PM
(#14320190)
What I find interesting is that methylation of cytosine, one common epigenetic modification, increases local mutation rates. Methylation typically reduces expression levels of nearby genes. A concomitant increase in local mutation rate may further disrupt transcription factor binding sites, also reducing expression. Thus, multi-generation methylation at a locus could increase the odds of genetically encoding the epigenetic information (assuming that the new selection pressure remains constant).
I've glossed over some details (e.g., somatic vs germ-line methylation patterns).
From the article it seems epigenetic mechanisms aren't inheritable i.e. they do not change the DNA just how the DNA is interpreted and/or which genes are activated. So even though epigenetic mechanisms might get passed on for several generations once the environmental factor affecting the mechanisms is removed the organisms would revert wouldn't they?
It seems all this does is allow some Lamarckian traits to act as a factors in the natural selection process.
Also the two explanations for how Giraffes got their long necks seem pretty ridiculous to me. Does anyone know of legit research into that topic?