4 ms·

Unified Theory of Evolution

24 points by yawz 10y ago

FullMtlAlcoholc 10y ago
Interesting. I wonder if the Environmental changes caused by climate change would accelerate epigenetic change. Also would it matter in a post-crispr era.?
mudil 10y ago
I am reading (for a review) upcoming book by Denis Noble called "Dance to the Tune of Life: Biological Relativity" (Cambridge Univ Press). In the book he lays out many important problems with neo-Darwinism, and neo-Lamarckism showing up in unexpected places. The big idea of the book is what we are seeing now with biology is what happened to physics when geocentric/antropocentric view of the world collapsed with Copernicus-Galileo-Newton-Einstein, and there was no center any more. Basically while Dawkins and other "high priests of neo-Darwinism" believe in centrality of genes (replicators), the new paradigm that is emerging is that there is nothing central to genes. "The genome is an organ of the cell," as Barbara McClintock said. DNA is just a dead molecule. There is so much more to evolution to consider than just building organisms around replicators, because there are so many different scales we need to consider: subatomic-atoms-molecules-polymers-organelles-cells-tissues-etc etc. And since it's hacking forum, the book discusses the other problem with DNA being the only book of life: it's an incomplete program to be responsible for creating a fully functional output, because it is linear without true logic elements.
Obi_Juan_Kenobi 10y ago
This is nonsense. Epigenetics did nothing to contradict Darwinian evolution, so no 'revision' is necessary. The references to Lamarck are utterly bizarre; giraffes are not lengthening their necks via epigentics, and the 'will' of organisms remains irrelevant to evolution. It is descriptive only insofar as it's somehow 'outside' Darwinian evolution, but that is not true. Epigenetics did a few things: * It showed that some multi-generational effects can be made from environmental influence. This is very interesting, with many fascinating effects, but this ultimately is controlled by the primary nucleotide sequence. Epigenetic regulation cannot occur without the proper target sequences, and no epigenetic modification can be maintained indefinitely. * It can do some 'tricks' (e.g. paramutation) that actually confound Mendelian inheritance, thus requiring revision in that sense. * It showed that gene regulation, viral defense, and defense from self-replicating genetic elements are all related in a wonderfully fascinating way. None of this overturns Darwinian ideas; they fit squarely on top of them. It is a further elaboration of the primary genetic sequence in much the same way that protein translation is. Evolutionary novelty still comes from changes to nucleotide sequence, and those sequences prosper according to chance and natural selection.
- somestag 10y ago
  In my reading of the article, I never detected a suggestion that Darwinian evolution was flawed or incorrect. In fact, as far as I can tell, the article says exactly what you're saying: that a complete understanding of evolution involves understanding that both evolutionary and epigenetic forces are at play. In other words, the template changes, but so does the expression of that template. In fact, the summary paragraph in the article says we need to add epigenetics to Darwinian evolution, just as you say these newer ideas "fit squarely on top" of Darwin's.
lvs 10y ago
Wow, OK. This article is awful and shouldn't be propagated. First of all, nobody serious is promoting any Lamarckian theory of evolution. The claim that mutation rates are too slow to explain phenotypes is completely bizarre. Nothing about modern measurements of mutation rate undercut Darwinianism or promote Lamarck. This is utter nonsense. If the framing was intended to present a molecular mechanism for inheritance via epigentics that is distict from classical genetics, then nothing about Lamarckianism is relevant whatsoever. We simply have expanded our understanding of genetics and short-term heritability to include epigenetic modifications, but modern genetics is not somehow in conflict with Darwin. Epigenetic changes occur during development and may be affected by externalities within an individual in a manner that biases the propagation of genotypes. But epigenetics is in no way teleological in the manner that Lamarck proposed.

24 points by yawz 10y ago

Interesting. I wonder if the Environmental changes caused by climate change would accelerate epigenetic change. Also would it matter in a post-crispr era.?

mudil 10y ago

I am reading (for a review) upcoming book by Denis Noble called "Dance to the Tune of Life: Biological Relativity" (Cambridge Univ Press). In the book he lays out many important problems with neo-Darwinism, and neo-Lamarckism showing up in unexpected places. The big idea of the book is what we are seeing now with biology is what happened to physics when geocentric/antropocentric view of the world collapsed with Copernicus-Galileo-Newton-Einstein, and there was no center any more. Basically while Dawkins and other "high priests of neo-Darwinism" believe in centrality of genes (replicators), the new paradigm that is emerging is that there is nothing central to genes. "The genome is an organ of the cell," as Barbara McClintock said. DNA is just a dead molecule. There is so much more to evolution to consider than just building organisms around replicators, because there are so many different scales we need to consider: subatomic-atoms-molecules-polymers-organelles-cells-tissues-etc etc. And since it's hacking forum, the book discusses the other problem with DNA being the only book of life: it's an incomplete program to be responsible for creating a fully functional output, because it is linear without true logic elements.

Obi_Juan_Kenobi 10y ago

This is nonsense. Epigenetics did nothing to contradict Darwinian evolution, so no 'revision' is necessary. The references to Lamarck are utterly bizarre; giraffes are not lengthening their necks via epigentics, and the 'will' of organisms remains irrelevant to evolution. It is descriptive only insofar as it's somehow 'outside' Darwinian evolution, but that is not true. Epigenetics did a few things: * It showed that some multi-generational effects can be made from environmental influence. This is very interesting, with many fascinating effects, but this ultimately is controlled by the primary nucleotide sequence. Epigenetic regulation cannot occur without the proper target sequences, and no epigenetic modification can be maintained indefinitely. * It can do some 'tricks' (e.g. paramutation) that actually confound Mendelian inheritance, thus requiring revision in that sense. * It showed that gene regulation, viral defense, and defense from self-replicating genetic elements are all related in a wonderfully fascinating way. None of this overturns Darwinian ideas; they fit squarely on top of them. It is a further elaboration of the primary genetic sequence in much the same way that protein translation is. Evolutionary novelty still comes from changes to nucleotide sequence, and those sequences prosper according to chance and natural selection.

somestag 10y ago
In my reading of the article, I never detected a suggestion that Darwinian evolution was flawed or incorrect. In fact, as far as I can tell, the article says exactly what you're saying: that a complete understanding of evolution involves understanding that both evolutionary and epigenetic forces are at play. In other words, the template changes, but so does the expression of that template. In fact, the summary paragraph in the article says we need to add epigenetics to Darwinian evolution, just as you say these newer ideas "fit squarely on top" of Darwin's.

lvs 10y ago

Wow, OK. This article is awful and shouldn't be propagated. First of all, nobody serious is promoting any Lamarckian theory of evolution. The claim that mutation rates are too slow to explain phenotypes is completely bizarre. Nothing about modern measurements of mutation rate undercut Darwinianism or promote Lamarck. This is utter nonsense. If the framing was intended to present a molecular mechanism for inheritance via epigentics that is distict from classical genetics, then nothing about Lamarckianism is relevant whatsoever. We simply have expanded our understanding of genetics and short-term heritability to include epigenetic modifications, but modern genetics is not somehow in conflict with Darwin. Epigenetic changes occur during development and may be affected by externalities within an individual in a manner that biases the propagation of genotypes. But epigenetics is in no way teleological in the manner that Lamarck proposed.