More FAPPery

Comments (7)

1. This is one of the poor ones. He just hammers on the point that certain traits are causally related to fitness without noticing that FAPP’s argument is meant to ask how we could possibly say of two coextensive traits that one was causally related and the other was not.

   The proper response here is quite simple: selection-for is a judgment made by real people using real background knowledge (about how organisms now interact with their environments). FAPP only allow bare historical data into the causal story: two coextensive traits, successful organism, nothing else. Indeed, with those two pieces of information NO causal story can be given.

   But we have a vast wealth of information that does factor into the selection-for causal judgment: we know now that a heart which did not pump blood but which merely made noise would quickly kill an animal. This causal judgment, just like ALL other causal judgments, is made against a wealth of background knowledge.

   1. FAPP’s argument is meant to ask how we could possibly say of two coextensive traits that one was causally related and the other was not.

      FAPP only allow bare historical data into the causal story: two coextensive traits, successful organism, nothing else.

      Well, I’m going to go off on a mini-rant on this topic again. Ever since the Origin, it was clear that natural selection worked on heritable variation. This particular question has never been controversial. Of course, the details of heridity itself were controversial for quite some time, but I digress…

      Anyway, any minimal but complete description of natural selection MUST MUST MUST admit heredity. If someone thinks they can defeat FAPP’s arguments without needing to adduce genetic evidence, more power to them. But for FAPP to claim victory without treating genetic arguments would be negligent and incomplete on their part.

      And the state of population genetics is sufficiently advanced in both theory and data collection that we can now infer natural selection (and quantify our uncertainty about such inferences) without ever looking at phenotype. Ideally, this purely genetic route would be part of a two-pronged approach and wouldn’t necessarily stand alone. But it could in a pinch.

      Given this state of affairs (and the apparent lacuna in FAPP’s treatment of genetics in a serious way) does this not show a hole in FAPP’s argument that you could drive a bus through? I wonder why nobody has been hammering this home?

      I mean, maybe (maybe) FAPP have a tiny point if they are bound and determined to admit only phenotypes and limited historical data. But why on earth should anyone using even a minimal description of natural selection agree to refrain from skewering FAPP’s argument from the genetic angle?

      For example, one could locate a sweeping or recently fixed allele with predictions that natural selection makes for linkage disequilibrium and/or site frequency spectrum data. Once such inferences are made, then one could leverage QTL mapping + candidate phenotypes or reverse genetics (for example) to figure out the phenotypic differences underlying the genetic change.

      Why does no other reviewer even mentions this in passing? Is it that the popgen / molecular evolution people don’t like to write book reviews? I’m sure Allen Orr could dust off his public intellectual duds, suit up, and ride to battle on this one. Hartl, Clark, Bustamante, Kreitman, Li, Wakeley, Gillespie, Charlesworth, Pritchard…? Nobody out there wants to venture a harsh review of this? Or have FAPP treated this and nobody has seen fit to discuss it in any of the reviews?

2. At the risk of annoying a Darwin guru, what is the focus on Darwin for? The important thing is modern evolutionary theory, not what some guy thought over a century ago.

   Science isn’t like philosophy with schools named after their founders, it’s based in reality.

   When I studied biology at university many years ago, Darwin didn’t get a mention in the several evolutionary biology courses I took. Why? Because we were looking at current theories, not their history.

   People arguing about Darwin’s contribution (a huge one, I have great respect for the chap, and a visit to Down House was a super experience!) are NOT arguing about science, they are arguing about history.

   1. Okay, I ordered a copy, and I will go through it in some detail, because I think there is a deep issue here, about intentionality in selection.

      But you are right – it doesn’t matter about Darwin; in fact, Darwin is out of the scene entirely since Fisher and Wright and Haldane developed the mathematics.

      1. I have to say I don’t understand what the “deep issue” about intentionality in selection is supposed to be. Unless you think there are issues with the intentionality of earthquakes, or comets. Some things can and do happen without intentionality. That includes changes in gene frequency, whether random or systematically biased by gene-environment interactions (aka natural selection).

         I can see from debates like this, as well as the continued popularity of Creationism/Intelligent Design, that this is clearly very difficult for many people to understand, but I’m a bit hazy on why.

   2. Sam C – I don’t think the focus is on Darwin — it’s on the sufficiency (or not) of natural selection to explain a lot of natural history. Just for the sake of contrast, suppose somebody wrote a book called “What Darwin Got Right” which argued that natural selection is, indeed, a vera causa.

3. A reply to Okasha by FAPP
   http://entertainment.timesonline.co.uk/tol/arts_and_entertainment/the_tls/article7110598.ece

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