Evolution, and the Trouble with Medical Research

I love the blog at the British Medical Journal, and I have a been a subscriber for some time. Typical of its great stuff are the following two summaries from the current NEJM:

The trouble with medical research is that it involves so much boring hard work. First carry out 2,446,431 person-years of follow-up involving questionnaires on aspirin use every two years. Having picked up 636 incident colorectal cancers, get all the paraffin-embedded histology specimens of these cancers and test them for the expression of cyclo-oxygenase-2 activity. Then analyse the data to determine the preventive effect of aspirin on colon cancers with and without COX-2 expression. You write up and rewrite the thing for the New England Journal and, hey, with luck you may be able to move yourself and your family to another ill-paid but more prestigious job in a distant university. Thank God there are people willing to do it.

And this:

By the time we turn 45, Evolution has largely lost interest in us, despite all the arguments about survival advantage from the extended family, altruism, and so forth. The human urinary tract is a good example. The Universe cares little whether older women leak when they cough, or older men get big prostates.

The second point is an interesting one. Will widespread longer life spans eventually mean that evolution ceases turning a blind eye to people over 45? One might think so, but then again, most of those people are past the point where they are propagating the species, so it remains more likely that evolution will continue to not favor middle-aged sorts.


  1. franklin stubbs says:

    Umm, yes. Err, no. Both.
    E.O. Wilson observed that we are the first species to have decommissioned natural selection.
    i.e. think of all the humans who thrive today thanks to some basic medical technology — including mundane stuff like footwear, eyeglasses, and penicillin — who would not have been able to survive in a non-technology enabled environment. To the degree that we can combat fitness landscape deficiencies with technology, we decommission the natural selection process for a host of vulnerable traits spanning all age groups.
    And yet, who’s to say that evolution only involves genes? In fact, who’s to say that evolution should be spoken of like some discrete ectoplasmic force in the first place?
    Maybe technological and cultural advancements ultimately represent a form of evolution just as powerful as, or even more powerful than, the traditional gene-based kind.
    In that regard, 45 year olds could be subject to just as many evolutionary forces as any other age group.
    And even here you can’t separate genes from the equation, as technology, culture, environment and genes are all mixed together in one glorious inseparable mess. Maybe in certain types of macro-economic environment, the entrepreneur gene thrives. Whereas in other environments, the bureaucrat gene thrives. (A gross oversimplification, but one with a point.) Maybe longstanding cultural trends filter back into RNA, via the same manner stressed female mice pass direct modifications onto their offspring. And so on.
    Sorry for the ramble. I just think this stuff is cool. (Can you dig it?)

  2. “Maybe technological and cultural advancements ultimately represent a form of evolution just as powerful as, or even more powerful than, the traditional gene-based kind.”
    The problem is that technological and cultural advancements don’t come with us, and can be lost.
    How many basic agricultural and industrial techniques have Americans forgotten because we’ve either progressed to more technologically-dependent methods or have completely shipped that work offshore?
    If all technological artifacts on Earth disappeared tomorrow, I suspect the people with an advantage would be those in the third world, who are more likely to know how to start again from scratch with sticks and rocks and plant fibers, and where fewer people have survived into adulthood because of technology.

  3. Thanks Jon. You beat me to it. While there can be little doubt that we pass on cultural/technical advancements, and that does represent a sort of advancement, it’s Lamarckism to suggest that it is anywhere near as blind-watchmaker resilient or important as evolution.

  4. franklin stubbs says:

    He he. Of course technology and culture are lamarckian — darwinian evolution is just too bloody slow to be of any use.
    As for resilience as some kind of quality descriptor elevating the importance and impact of darwinian evolution over lamarckian, I find that notion amusing… touchingly romantic in a weird luddite sort of way. There is no analogue for what exists now in our darwinian past… but why would you want there to be? Do you really mean to infer that an average lifespan of 30, with high possibility of violent death at all points between, is preferable to the trappings of modern society?
    And does primitive man really have superior survival capabilities in comparison to modern man? What possible scenario, for example, would cause “all technological artifacts on earth to disappear” without also causing the human race to disappear? It’s not plausible even in the conceptual realm, just as imagining a world without electricity is not plausible — because electrical processes are fundamental to physics and life, not just machines.
    Such a mindset sounds to me like advocating businesses not use computer networks because the network might break down — or suggesting there is some kind of hidden luddite advantage in such. I don’t see one.
    Darwinian evolution has no agenda and plays no favorites. (How could it? It’s not even an “it.”) As such, the supposed “resilience” of evolution could be a mere statistical fluke, as far as mankind’s survival is concerned.
    Michio Kaku points out that mankind’s long-term is ultimately dependent on mastery of technology on a grand scale. Why? Because, at some point, some unprecedented natural event will come along that kills us. An ice age, a meteor, a comet storm, a supernova, who knows. When that event comes, as odds predict it must at some point, the human race will have to rely on technological advances to prevent it, mitigate it, and / or otherwise survive it.
    In that sense, truly long-term survival of the species depends on evolution of the lamarckian kind. Unless we intend to join the 95%+ (or whatever the number is) of species whom mother nature has blithely sent to the wall.

  5. franklin stubbs says:

    p.s. and by the way — we don’t know enough to say for certain that Lamarckian processes never impact Darwinian processes.
    Cultural shifts are a Lamarckian process — in the sense that they are passed from one generation to the next within a lifetime — and studies of female mice have shown single-generation gene changes based on environmental stresses are possible also.
    ‘Lamarckism’ is not everywhere an insult. Lamarck just got things wrong in applying his ideas directly to genes. His concepts apply in cultural form, and now we see that evolution is strange enough, and in some cases rapid enough, for culture to have a potential short term effect on genes.