So far there are almost 200 votes and "EvoDevo" is leading the pack (Boo!). I'm delighted to see that "Nonadaptive Evolution of Complexity" is getting a substantial number of votes. It suggests that there are people who really do understand Michael Lynch and Eugene Koonin (among others).
"Epigenetics" is way too popular. It is NOT an addition to evolutionary theory, in my humble opinion.
Nobody has voted for "Theistic Evolution."
VOTE NOW!
13 comments :
I find it strange that these "extended synthesis" discussions always manage to avoid mentioning one of the hugest things that has happened in the last 30 years in evolutionary biology, i.e. phylogenetics and "macroevolution" in the sense of lineage dynamics (the factors that influence rates of lineage splitting and lineage ending, ie extinction). "Species sorting" does that a little bit but its basically a term from the 1980s that no one uses...
Obviously a few simple words may sometimes fail to express the different meanings people assign to the same words. I would be interested in what others think--esp. Prof. Moran--but my take on just one issue is the word "epigenetics" is pretty ambiguous.
If one means epigenetics as the current fad of just meaning the changing methyl groups on DNA or similar modification to DNA, I certainly agree it is *not* a major "modification" to evolutionary theory.
If, however, one means epigenetics in its classic meaning of overall development, then it is a major item missing, IMHO. The neoDarwinian synthesis brought together Mendelism and Darwinism, but deliberately ignored the complexity of development and physiology. The classical and many many molecular models in evolutionary theory do a poor job of explaining the developmental and physiological mechanisms between genotype and phenotype and their role in changing system complexity. The cell signalling networks and their gene regulatory network "targets" are both not well explained or understood by the current theory. These two networks exist most strongly in metaphyta and metazoa, of course, but have basic progenitors in unicellular organsisms.
These networks help complexity emerge from an embryo and play a role in changing complexities. As Gould once implied, if there is to be a final synthesis in biology, it will be on the common playing field of developmental biology.
Even when some changes are-in the abstract- "in the genes", I suspect that many of these changes will not be understood among the background of many neutral changes without understanding how these changes play out in developmental networks.
Why's Ray Comfort's theory of evolution not on here? You know, the one where "a dog evolves after millions of years" - but there's no female around because it didn't evolve yet. And where the fact the dog has eyes, ears and a nose is an inexplicable miracle.
That's my all-time favorite "theory of evolution".
Maybe next time?
BTW, that reminds me that I also forgot the "Banana Theory of Evolution."
I wonder how many people would have voted for that?
Epigenetics" is way too popular. It is NOT an addition to evolutionary theory, in my humble opinion
Outside of the media I don't see where epigenetics is more overhyped by its proponents than any other field but for some reason it's singled out again and again. Why is that?
Nobody has voted for "Theistic Evolution."
Well, five people apparently have (so far), even if such a level of support is comparable with quantum vacuum fluctuations.
"Theistic Evolution." Really? That's the ultimate oxymoron. I think it refers to the culling out of some the inconvenient gospels from the "offical" bible back in the Dark Ages I. Dark Ages II is where we're heading if the unholy trinity (Bohner-Cantor-Ryan) gets their way.
I think EvoDevo encapsulates the definition of epigenetics that is actually important in evolution. Done right, it should include the physical processes by which regulatory networks turn into morphology.
Indeed.
Does anyone know when epigenetics came to be defined almost solely as methylation of DNA sequences? It's as if the proponents of epigenetics' importance are shooting themselves in the foot here.
(A good example of epigenetics is the non-genetic structural inheritance of flagella/cilia patterns in protists, as well as prions. (It's discussed in Jablonka and Lamb's Evolution in Four Dimensions, pages 121-126.))
The theory of evolution by Natural Selection can fully explain all the data generated in evolutionary science during the last century and a half; therefore, it makes little sense to just add various secondary evolutionary perspectives to it, which only create confusion.
Take, for example, this statement by Larry Moran displaying a completely confusing situation:
“I'm delighted to see that "Nonadaptive Evolution of Complexity" is getting a substantial number of votes. It suggests that there are people who really do understand Michael Lynch and Eugene Koonin (among others).”
This statement makes little sense considering, for example, a recent publication by one of these authors (i.e. Koonin) entitled: Gene frequency distributions reject a neutral model of genome evolution (available for free at: http://www.ncbi.nlm.nih.gov/pubmed/23315380)
The theory of evolution by Natural Selection can fully explain all the data generated in evolutionary science during the last century and a half; ...
Really? Then explain why there's an approximate molecular clock.
Explain why there's so much variation in most populations.
Explain pseudogenes.
Explain why some people can roll their tongues and others can't.
Explain mass extinctions.
Explain why there are so many marsupials in Australia.
Explain sex.
Explain punctuated equilibria.
Explain random genetic drift.
Give us an adaptationist explanation of junk DNA that most evolutionary biologists will believe.
Claudiu Bandea said,
This statement makes little sense considering, for example, a recent publication by one of these authors (i.e. Koonin) entitled: Gene frequency distributions reject a neutral model of genome evolution
Koonin's group has shown that there is a core group of genes found in all species and that this core group of genes (about 100 genes) is preserved by selection. The gain or loss of most other genes (about 2000) give rise to substantial variation in gene content even between closely related species. That gain or loss is probably neutral over the long term.
Some recent work suggested that a neutral model would account for the gain or loss of ALL genes in the genome, including the core genes.
So, Claudiu, what's your point?
I think you and other evolutionary biologists might be confused by the fact that natural selection has a stochastic dimension, just like many other biological phenomena. For example, the most fitted lion might get struck by lightning, and a less fitted lion might to be at the right place at the right time to mate.
The examples you gave are consistent with the activity of Natural Selection as the only force directing evolution, including the preservation of the so called “junk DNA ’in various genomes as I discussed at length here and elsewhere.
The reason I mentioned Koonin’s model showing that “the neutral model of genome evolution, with the same replacement rate for all genes, can be confidently rejected”, was not to necessarily make the case that the concept of neutral evolution is flawed, but to point out to the confusion generated by all these secondary theories of evolution, which appear and often disappear more or less stochastically from one generation of scientists to another or even faster.
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