The talk begins with a warning that evolution has gone beyond Darwinism. Lynch emphasizes, "Mutation, drift, and the origin of subcellular features." If you haven't been able to follow the discussion on the perils of adaptationism, then watch this lecture to get a sense of what it's all about.
I'm a big fan of Michael Lynch and I hope you will also be a fan after you learn more about his views.
I was Lynch's host, and was at the talk and my memory of it was that it was just against naive adaptationism, not against Darwin or "Darwinism". He even endorsed selection-mutation balance for the evolutionary constrained optimization of mutation rate, IIRC. It's not like Lynch beat up the Darwin puppet or anything: https://twitter.com/nickjmatzke/status/565196097917046785
ReplyDeleteIn my naive understanding, adaptations are likely driven by selection, and molecular changes are mostly the result of drift. "Neutral" molecular changes enable or bootstrap adaptive evolution. It seems to me that having a lot of neutral alleles around in a population creates opportunities for adaptation. That would be the fatal flaw in Behe's Edge.
ReplyDeleteIf this is wrong, it is because my understanding is weak. I'd appreciate correction or clarification.
That's a pretty good understanding of my view except that I'd include a lot of phenotypic change in the neutral category ( i.e. not just molecular change).
DeleteI also like to emphasize the fact that slightly detrimental alleles can become fixed in a population.
Larry, let me ask you and the readers of Sandwalk a straightforward question about neutral theory:
DeleteIs any useful biological features, whether at molecular or phenotypic level, maintained by neutral evolution or not?
Doesn't that question answer itself? In so far as they are "maintained"(as in something is actively keeping it in a working state), it isn't strictly neutral.
DeleteIf one defines function as "selected effect", functions are "maintained" by natural selection ex definitione. But, if I understand Lynch correctly, (nearly) neutral evolution has a lot to do with the rise of functions.
Delete"Is any useful biological features, whether at molecular or phenotypic level, maintained by neutral evolution or not?"
DeleteNot.
Thanks for your answers. So, to summarize, unlike evolution by natural selection, neutral evolution can not maintain useful molecular or phenotypic features.
DeleteSo, is it correct to state that only natural selection can preserve a useful molecular or phenotypic feature?
As pointed out by Piotr, however, neutral evolution can apparently "rise" useful molecular or phenotypic features, but without natural selection acting upon them, by definition they can not be useful. Is that correct?
Claudiu,
DeleteIt sounds like you are just learning about this for the first time. Is that true or are you trying to set me up for some rhetorical gotcha?
Either way, you are wasting my time.
I think it is important to understand what is neutral evolution and what it does. For instance:
Delete(i) According to Motoo Kimura and Jack King "neutral evolution" only acts at the molecular level, not at the phenotypic level. True or false?
(ii) At the molecular level, neutral evolution only acts on non-informational genomic sequences. True or false?
(iii) If neutral evolution does not act on genomic sequences that are evolutionary significant, then it is irrelevant. True or false?
(iv) Why can't DNA sequences that are products of neutral evolution be beneficial to the organisms that carry them in the absence of natural selection?
(i) False
Delete(ii) False
(iii) True (but the premise is incorrect)
(iv) Because then the alleles wouldn't be neutral.
Claudiu: As pointed out by Piotr, however, neutral evolution can apparently "rise" useful molecular or phenotypic features, but without natural selection acting upon them, by definition they can not be useful. Is that correct?
DeleteI didn't say anything remotely like this. Please don't put nonsense in my mouth.
Piotr: "I didn't say anything remotely like this. Please don't put nonsense in my mouth.
DeleteWell, what did you mean when you wrote: But, if I understand Lynch correctly, (nearly) neutral evolution has a lot to do with the rise of functions."
Larry:
Delete(i) False
If there are phenotypic traits that evolve neutrally, are these traits biologically functional or non-functional?
(ii) False
Do any of the informational and non-informational sequences that evolve neutrally have biological functions?
(iii) True (but the premise is incorrect)
Why is the premise incorrect?
(iv) Because then the alleles wouldn't be neutral.
Are you saying that the alleles that evolve neutrally are by definition non-functional?
(i) Functional (mostly)
Delete(ii) Yes
(iii) Because it is.
(iv) No
So, apparently, you think that some of the phenotypic features and genomic sequences that evolve neutrally (i.e. in absence of natural selection) are functional. Is that true?
DeleteThanks for your straight answers.
DeleteNick,
ReplyDeleteI copied the title of the post from the beginning of his talk.
OMG!!!
ReplyDeleteLarry, give me a break.!!
Break granted.
DeleteBye.
Watched a little bit.
ReplyDeleteWhy don't most biologists and evolutionary biologists know lots of stuff has happened since Darwin? how could this lack of info occur? how many is that relative to ones up to date?
I thought it was funny he said many specd their whole career trying to see how semection brought this or that about IMPLYING they wasted their career.
A creationist had this hunch long before!
Its so much guessing about unobserved things. Where is the science beyond mere observing present biology etc.?
A creationist had this hunch long before!
DeleteBut you are not understanding the points being made, Robert. Selection in nature will be inevitable. Its just that not all features are adaptive and selected for. So, like many creationist hunches, yours is wrong.
Its so much guessing about unobserved things.
Actually its guessing about observed things. Which is fine as long as speculation does not obscure other possibilities.
Now, if you want to talk about the "guessing about unobserved things", you should examine religious beliefs before taking a stab at scientific matters.
I meant the hunch as that they waste their yime period in figuring out selections trails in leading to this or that.
DeleteIts guessing in almost all of its great attempts to draw conclusion. just like those, he admits, waste their time guessing about selections trails.
It confirms to me that few researchers Actually get into the details.
I am always unsure how many evoltionist researchers there are and how many evolutionists think there are.
I think few and thats why error dominates it , and in the past, and why ID/TEC has so easily become a serious threat to it all.
Our few easily take on their few. relative.
Paul Nelson on EnV
ReplyDeleteLarry Moran, the University of Toronto biochemist and maverick "non-Darwinian" evolutionist, is an admirer of Indiana University evolutionary biologist Michael Lynch.
Maverick... oh dear.
I have to be a "maverick" because, like Michael Lynch, I'm dead wrong about evolution according to Paul Nelson.
DeleteUnfortunately for Paul Nelson, the folks over at Uncommon Descent have decided that Michael Lynch is an authority on evolutionary theory and Paul Nelson isn't.
Unfortunately for Paul Nelson, the folks over at Uncommon Descent have decided that Michael Lynch is an authority on evolutionary theory and Paul Nelson isn't.
DeleteWhich reminds me - have you noticed how many times they have used his papers as "proof" against evolution?
Money quote from Nelson's blog post:
DeleteIf more evolutionary theory were done with this sort of meticulous care, the debate pitting ID versus neo-Darwinism would be a lot more tractable.
That's right. The entire debate is over ID Creationism vs. Neo-Darwinism. Therefore, if Neo-Darwinism is false, then the only logical conclusion is that ID creationism is true. QED.