16 Responses to “Open Thread: Basket Kittens”
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The Design Matrix: A Consilience of Clues by Mike Gene 
Your Inner Fish: A Journey into the 3.5-Billion-Year History of the Human Body 
Catalyzing Inquiry at the Interface of Computing and Biology 
System Modeling in Cellular Biology: From Concepts to Nuts and Bolts 
The Plausibility of Life By Marc W. Kirschner and John C. Gerhart 
Agents Under Fire by Angus Menuge 
Life's Solution by Simon Conway Morris 
Information Theory, Evolution and the Origin of Life by Hubert P. Yockey 
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Nature, Design, and Science by Del Ratzsch 
Origination of Organismal Form by Muller & Newman 
Biased Embryos and Evolution by Wallace Arthur 
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Evolution in Four Dimensions by Eva Jablonka & Marion Lamb 
The Evolution-Creation Struggle by Michael Ruse
April 17th, 2009 at 10:06 pm
Hey all,
As much as I love the politics and theology I would like to see a little more science around here.
Here is some recent stuff with implications for frontloading
Can you say modularity
Cold blooded animals acting like warm blooded ones? Who you calling primitive ?
Here is one for Joy.
Lamarck any one.
peace
Comment by fifth monarchy man — April 17, 2009 @ 10:06 pm
April 17th, 2009 at 10:22 pm
Let me quote from Eugene Koonin’s recent paper, “Darwinian evolution in the light of genomics” (Nucleic Acids Research, 2009, 1–24). These are two excerpts from where he is outlining the principal concepts of the Modern Synthesis.
And
Now, I have two questions:
Why did Darwin insist on "strict gradualism as an essential staple of his theory"?
Why did most proponents of the Modern synthesis reject "drift as an important evolutionary force, and adhered to a purely adaptationist model of evolution"?
Comment by MikeGene — April 17, 2009 @ 10:22 pm
April 17th, 2009 at 10:22 pm
Thanks for the links, FMM. Interesting stuff!
Comment by nullasalus — April 17, 2009 @ 10:22 pm
April 18th, 2009 at 7:34 am
From the worm link
quote:
In fact, they even use steroid hormones to do this, just as we do to regulate our temperature," she said, noting that this might have been a very early evolutionary link between cold- and warm-blooded animals.
end quote
It seems that a mechanism for regulating body temp was there millions of years before warm blooded animals put it to use for that purpose. Perhaps it was there from the very beginning of multicellularity.
I would not be surprised if the genes involved are very very similar and all that was needed was a minor tweak to their expression.
I’ll go out on a limb and call that my fifth frontloading prediction.
To bad FLE is scientifically vacuous It could lead to all kinds of interesting research.
peace
Comment by fifth monarchy man — April 18, 2009 @ 7:34 am
April 18th, 2009 at 9:35 pm
My goodness. Are critics so engrossed in defending contemporary politicicians that they neglect to respond to Mike Gene's doubts about prevailing biological wisdom?
Comment by Bradford — April 18, 2009 @ 9:35 pm
April 19th, 2009 at 4:57 am
Bradford:
It seems to me that MIke Gene tried to express doubts about outdated biological wisdom rather than prevailing biological wisdom. Maybe the critics are not too interested in attacking straw men?
But very briefly then:
Why did Darwin adhere to strict gradualism? [late 19th century wisdom] Presumably because he had the wrong idea about the mechanisms of inheritance and mutation.
Why did most modern synthesis proponents reject drift as important? [mid-20th century wisdom] Perhaps they were convinced by Fisher's arguments. Selection (adaptation) is more efficient in large populations.
BTW, Fisher also gave reasons why small rather than large mutations are more likely to be the generator of adaptive variation. He also believed that all mutations were created by God, hardly RM.
Comment by Raevmo — April 19, 2009 @ 4:57 am
April 19th, 2009 at 11:44 am
I’m not expressing doubts or raising straw men. I merely quoted two excerpts from Koonin and asked two questions about history.
That’s part of it, but there is more. Nevertheless, according to Koonin, the Modern Synthesis adhered to strict gradualism. We can’t blame that on those wrong ideas about the mechanisms of inheritance and mutation. So why did the modern synthesis insist on strict gradualism?
Are you saying they rejected drift because they thought evolution only occurred in large populations?
Comment by MikeGene — April 19, 2009 @ 11:44 am
April 19th, 2009 at 12:40 pm
Mike Gene:
So you already know the answer and your question was rhetorical?
Well, the MS was formulated before the discovery of the structure of DNA and the nature of genes, etc. Not much was known about the mechanisms of inheritance and mutation.
I don't know that the MS "insisted" on gradualism. It may in part be explained by the fact that the MS tried to unify the biometricians who studied continuously varying traits and the mendelians who studied particulate inheritance. The mathematical machinery of the MS models was partly borrowed from the differential equation approach in physics.
No. However, it can be argued, as Fisher did, that adaptations are more likely to evolve in large populations. But another main "architect" – and enemy of Fisher – of the MS, Sewell Wright, did not reject drift at all but believed it to be very important for local populations to "cross fitness valleys" and not get stuck on local fitness peaks. There have always been a variety of views on the relative importance of neutral and deterministic processes in evolution.
But I have the feeling that you have your own answers already.
Comment by Raevmo — April 19, 2009 @ 12:40 pm
April 19th, 2009 at 6:02 pm
BTW, Mike, if you're interested in the history of the ideas, may I recommend "The Origin of Theoretical Population Genetics" by William B Provine (1971) and "A Reason for Everything" by Marek Kohn (2004). I can send you my copies if you promise to send them back.
Comment by Raevmo — April 19, 2009 @ 6:02 pm
April 19th, 2009 at 7:31 pm
Hi Ravemo,
I don’t claim to know the answer. I do know that when it comes to questions like “why?”, often times more than one factor is in play. And while I do have my own hypotheses, I was hoping to hear the opinions of others who are more knowledgeable.
As far as the MS and heredity goes, yes, I know DNA had not been characterized yet. But as Allen MacNeill notes, “As a result of their work, Darwin's theories of natural and sexual selection were combined with Mendelian genetics, biometry and statistics, demography, paleontology, comparative anatomy, botany, and (more recently) molecular genetics and ethology to produce a "grand unified theory" of the origin and evolution of life on Earth.”
In other words, while Darwin may have been influenced by blending theory while speaking of gemmules, this would not apply to the MS.
So I am still left wondering why strict gradualism, starting with Darwin and culminating in the MS, was deemed to be such a principal concept.
As far as the rejection of Neutral Theory, we’re still left with Koonin’s description: “the Modern Synthesis, in its ‘hardened’ form (13), effectively, rejected drift as an important evolutionary force, and adhered to a purely adaptationist model of evolution (17)"” and I’m left wondering why this was.
I did find this from Gert Korthof:
Interesting, as this would also partially explain the devotion to strict gradualism.
Anyway, thanks for the book offers. I’ll see if my library has them and try to get one or two over the summer. If I had to choose one, which would you recommend?
Comment by MikeGene — April 19, 2009 @ 7:31 pm
April 19th, 2009 at 7:39 pm
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Pingback by Welcome Cat « The Design Matrix — April 19, 2009 @ 7:39 pm
April 20th, 2009 at 12:34 pm
Mike Gene:
I'm still wondering what you mean by "strict gradualism". I take gradualism to mean that phenotypic evolution proceeds primarily by the accumulation of many relatively small steps. Anyway, during the late 19th centure and early 20th century there was a fierce battle between the proponents of "discontinuous" (saltationist if you like) evolution and "continuous" (gradualistic) evolution. From 1918 onwards, Fisher, Haldane, Wright et al. showed mathematically that particulate Mendelian inheritance of multiple genes can easily lead to continuous variation in traits, and moreover that weak selection on small variations can be surprisingly effective in producing large phenotypic changes over relatively little time. A lot of work on experimental selection at the time supported these conclusions and contradicted those of the "saltanionists". Thus it is not surprising at all that the architects of the MS believed gradualism to be such a principal concept.
Like I said before, some major players like Wright and, to a lesser extent, Haldane did consider drift to be important, but I think mostly for theoretical reasons. Perhaps there simply wasn't that much evidence for the importance of drift, compared to the many studies that had shown the effectiveness of selection in bringing about change.
I don't follow.
Provine's. It's more scholarly historic. Kohn's is more anecdotal (and hilarious at times) and focuses on English academia.
Comment by Raevmo — April 20, 2009 @ 12:34 pm
April 21st, 2009 at 2:49 pm
The larger financial institutions which received TARP money now wish to repay the money but must get permission to do so. That's one difference between a private and government lending source. Normally repayment of a loan would be a welcome development. But if the government accepts the money, which was derived from the taxpayers and still should be considered their money, it would lose its basis for control of the banking sector of the economy. Since there is no longer even a perceived threat of economic collapse political threatiness has lost whatever credibility it had. Take the money back Geithner.
Comment by Bradford — April 21, 2009 @ 2:49 pm
April 23rd, 2009 at 11:55 pm
Hi Raevmo,
Ask Eugene Koonin. I’m merely quoting from him: “Darwin insisted on strict gradualism as an essential staple of his theory”
Darwin did not insist on “relatively” small steps (relative to what?). Darwin wrote, “Natural selection can act only by the preservation and accumulation of infinitesimally small inherited modifications, each profitable to the preserved being”
Comment by MikeGene — April 23, 2009 @ 11:55 pm
April 24th, 2009 at 8:32 am
Of course it was relative, relative to the phenotypic variation that Darwin observed in populations.
There is a typical distribution of trait specifics around a mean, and natural selection works within this distribution. This tends to bunch the variation into a narrow spectrum, and the hypothesis was that new variations would be introduced by some yet unknown mechanism. The discovery of genetics and mutations revealed part of this story. One important facet was that variation was discovered not to be continuous, but particulate. That is, not indefinitely small, but in *discrete* quantities.
Darwin allowed for differing rates of evolution, but believed that adaptation proceeded in small increments. There are many examples of this incremental process in historical evolution. This is a valid first-order approximation.
It turns out that evolution can proceed much faster, and does proceed much faster, than Darwin could readily admit, under certain circumstances. This can result in discontinuities on the geological scale. But in this view, evolution is still gradual on the order of generations. A second-order approximation.
Evolution is still seen as largely incremental, though even this may not always be correct. Modern models might resemble scale free histories; lots of small changes, a few big changes, and the rare revolution.
Comment by Zachriel — April 24, 2009 @ 8:32 am
April 24th, 2009 at 1:12 pm
Yet another example of the Santa Claus mentality pervading contemporary America. This from Yahoo news:
This report did not mention that GM has plans to shut down manufacturing plants for nine weeks during the summer. A good idea when supply exceeds demand but workers will be paid for the entire nine weeks. A nine week paid vacation from a company that is broke. No wonder our companies do not compete well. The solution is not to take money from productive companies and taxpayers and funnel it to inefficient companies. But we can have it all. Right? Uncle Sam can play Santa with no repercussions. Free lunches gone wild. This stuff will come home to roost.
Comment by Bradford — April 24, 2009 @ 1:12 pm