Apparently, natural selection acting on populations to randomly determine which lineages go forward may not be the only force at work in evolution. Organisms appear capable in some circumstances of adapting their genomes in response to pressures to some degree. I find this surprising but not alarming. I’m no scientist so I wonder what those of you who are think of this. Is it credible?
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Oh, ho! You are now ripe for Greg Bear’s “Darwin’s” books.
I still have the one I checked out of the SF library. But when would I read it? Too many pans on the stove already. I’ve always liked good nonfiction but in the last several years have learned to love good fiction. My fear is that this will be fiction in the service of a rational agenda, essentially propaganda. Am I being paranoid?
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Put down your guard. Bear is wonderful. In the private thread where we talked a it with Martin about Bear’s books, i quoted a section I think will particularly speak to you. What he does in that passage would be anathama to Asimov.
Bear is an entirely different world for me , but a very good one.
- “Neo-Darwinistic Determinism” [Richard Dawkins’ Selfish Gene] vs. “The Third Way: Stochasticity” [Denis Noble].
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Most evolutionary biologists I know take articles such as this as a tempest in a teapot. Of course, one is always learning new details of genetic mechanisms, but this doesn’t overturn the basic ideas of Darwin (or Dawkins) of evolution by natural selection. Here’s a response by Jerry Coyne to such articles (there was one that appeared in the Guardian a few years ago):
*This article in the Guardian really says nothing new beyond what a dozen articles have said already: “There are things we know about evolution that Darwin never imagined, and we’ve made many discoveries that weren’t part of the ‘modern synthetic theory of evolution’ forged in the Thirties and Forties.” I’ve posted a ton about these issues already, many of which are said to form an “Extended Evolutionary Synthesis”, or EES. It turns out that yes, things like the neutral theory and epigenetics weren’t imagined by Darwin, who knew nothing about heredity, or even by the great Theodosius Dobzhansky, but the exponents of the EES sometimes try to pretend that it’s more than an extension of evolutionary biology, but a Kuhnian “revolution” mandating a “new theory of evolution”.
But in fact we do not need a new theory of evolution: the basic theory proposed by Darwin in 1859, which includes gradualism, variation, natural selection as a critical factor responsible for adaptation, splitting of lineages, and the resultant common ancestry of all species and individuals, still holds. But we know a lot more now, and most of it can easily be incorporated into evolutionary biology. In fact, if you look at evolution textbooks from a few years ago, you’ll find phenomena like epigenesis, the neutral theory, “niche construction”, plasticity, and the like not only discussed, but shown to have been part of discussions about evolution for half a century or more. Now they’re simply part of “evolutionary biology”, which, yes, has expanded, but not in a manner that mandates replacing the old theory. Like cosmology, we just add new stuff to the field as it turns up, and ditch the stuff that turns out to be wrong.
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Wow and thank you. I wonder why we don’t hear more about this? Most discussion of evolution does seem too simplistic - but not because it is failing to leave room for supernatural agency. The naïveté of thinking of genes as selfish agents seems like an unintended consequence of someone eager to rule out anything but a mechanistic understanding of life.
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Except that Dawkins never espoused a naive concept of the “selfish gene”…publicists continue to misinterpret what Dawkins was trying to say. Dawkins has said that he now regrets using that term because it has caused so much confusion.
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Well that’s good to hear. Everyone critical of his penchant for anti religious debate nonetheless give him props for his science.
Well he did title a book in a way that would give that impression. But I just wonder why he feels the need to argue against religion by drawing on the science he knows.
Yes, whereas I admire Dawkins for science, I think he steps out of bounds (and reveals a lot of ignorance) when straying into questions of philosophy and religion!
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The same goes for J. Coyne whose blog I quoted above. I think he’s a lucid evolutionary biologist but I read his book “Faith vs. fact: why evolution and religion are incompatible” and nearly threw it across the room several times as I forced myself through. Of course, he chooses the non Christian definition of faith as “believing something in spite of the evidence” or “believing something you know isn’t true”. Uggg.
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It makes anyone question his judgment who isn’t consumed by the polemic on one side or the other.
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I’ve never read anything in the science vs religion genre. Of course if I were a Christian in the sciences I might be more tempted. Hopefully that was enough to inoculate you against the urge to sample anymore aggravation from that well.
Yeah…sometimes one’s reading can be a bit masochistic, eh? Well, I try to read widely, even of people I think I might disagree with, to be exposed to a range of views and to avoid the follies of my own echo-chamber. But all that in small doses 
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In biology, this is called phenotypic plasticity. In the vast, vast majority of cases, any epigenetic changes that occur in response to environmental challenges are not hereditary. Therefore, it is the ability to change phenotypes and change epigenetic patterns that is heritable, and this fits in quite well with long standing theories on evolution. There are a limited number of cases where epigenetic changes are heritable, but these are very limited in their scope. As with everything in biology, there are exceptions to every rule, but this doesn’t make the general rules go away.
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Everyone I read seems to agree about that. But it does suggest that life isn’t just the playing out of deterministic billiard balls, and the selfish gene metaphor is not apt.
That’s a bit of salesmanship. The real situation in biology is very different. The vast majority of biologists have a dim view or the “Third Way” or “The Extended Evolutionary Synthesis” because the very first thing its proponents do is misrepresent both the theory of evolution and what biologists are doing. All of the mechanisms they tout are already a part of the theory, so there really isn’t anything to extend.
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Mutations were found to be random with respect to fitness clear back in the 1950’s, so I don’t think evolution has been considered deterministic for quite some time. At the heart of Neutral theory is the non-deterministic fixation of neutral mutations, as another example.
As to the selfish gene metaphor, I think it still applies. Genes that increase their rate of reproduction compared to competing genes will necessarily increase in number within a population.
Yes, I think this interpretation of a “selfish gene” holds. But some populists of science have misinterpreted “the selfish gene” to mean that Dawkins actually (naively) thought there was a single gene that deterministically encodes “selfishness”.
IMO, one of the best articles on the Extended Evolutionary Synthesis was written by Carl Zimmer in Quanta Magazine.
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