Evolving Thoughts

Book review: Freaks of Nature

“Freaks of Nature: What Anomalies Tell Us About Development and Evolution” (Mark S. Blumberg)

This book came to me well recommended, and as far as the content goes, I am very impressed. The writing style, however, and the intended audience, are at odds with each other.

Blumberg is a developmental biologist who has a real grasp of the topic, is enthusiastic about it, and has a clear target in his sights. That target is sometimes misleadingly called “The Modern Synthesis”, although a better term might be something like “gene centrism”; the view often expressed in words like “genes are the program that controls the development of the organism”, or “genes are information about the phenotype”. Rightly so, Blumberg attacks this in what starts out as an accessible argument, based initially on the developmental errors that lead to one, three or four eyes in vertebrates, which are errors of timing based on the expression or not of (among other things) the Sonic hedgehog homolog gene, or Shh.*

He traverses the past century or more of experiments on developmental errors, and shows how the notion of the gene centrists that “it’s all in the genes” has effectively been abandoned, although the terminology remains and many authors still fall back into the mindset when they aren’t being careful. Implications of this include the total destruction of the “nature-nurture” divide. You simply can’t have genes do anything (nature) without there being an environment that triggers, delays, and generally shepherds the development of the organism. If you doubt this, by the way, consider what genes do in a fetus in a vacuum.

Thus far, engrossing and interesting. He then moves into sex determination, covering everything from fishes that swap sexes serially to intersex children among humans, and the lack of total control by any single set of causes. But here the message of the book starts to move away from the initial target a bit, and it becomes technical, with apologies for the acronyms appearing in the body of the text. While anyone who has an acquaintance with biology will cope, the ordinary reader who is not scientifically aware may struggle. It’s not a complete obstacle, but it is guaranteed to reduce the audience of this crucial message.

And the message itself struck me as left in the air a bit – something I am especially attuned to as I do it myself so often. There is a deep and important implication of the developmentalist challenge to gene centrism: taxonomic entities like races, genders, species and other groups of organisms simply lack a genetic “essence”. Blumberg didn’t bring that out. Maybe he has other concerns, but I would love to have seen a chapter on that.

These quibbles aside, I do recommend this book for the science enthusiast, the undergraduate science student, medical professionals, conservationists and so on. It is a good entré into a field that is resurging even as the molecular hegemony seems to have carried all before it.

* In technical papers, the gene is always written in italics, and the product of the gene, a protein which often has the same name, is written in roman text: Shh.

Comments

  1. #1 Roberto Keller
    February 3, 2009

    Oh, this book has been in my Amazon shopping card for a couple of weeks now. I guess is time to stop being so cheap and click that buy button.

    P.S. Like the new banner better.

  2. #2 Frasque
    February 4, 2009

    I definately want to check this out, it sounds similar to LeRoi’s “Mutants”, which I enjoyed quite a bit.

  3. #3 Chris L
    February 4, 2009

    I haven’t seen this book, but I’m glad someone has written it. Mary-Jane West-Eberhard’s opus is massively complete, but massively hard to read…

  4. #4 origin
    February 8, 2009

    Wilkins:

    Jerry Coyne had a review of this book that was recently published in Nature:
    http://www.nature.com/nature/journal/v457/n7228/full/457382a.html

    Coyne’s review has quite a different tone than yours. I was wondering if you would be so kind as to comment on Coyne’s response, point out if your views differ where and why, etc.

  5. #5 Mark Blumberg
    February 10, 2009

    In response to Origin’s comment regarding Coyne’s review of my book, Freaks of Nature, I only ask that you not assume that my book was described accurately in that review (it wasn’t). A brief response to Coyne’s review will be published in Nature this week and I hope to have a more extended response available soon on a blog as yet to be determined.

  6. #6 John S. Wilkins
    February 10, 2009

    Having now seen Coyne’s review, I tend to agree. Coyne is holding out for the view that genes are the base and all of evolution, while Blumberg is explicitly of the view that development cannot be ignored when looking at the effects of genes and that genes very often “code for” an inductible range of traits rather than a particular trait. With Coyne I get the impression he’s defending the Maginot Line for Neo-Darwinism.

    Those who defend gene centrism hold that at base everything is genetic. A simple thought experiment shows otherwise – what will genes do in an organism in a hard vacuum? Environmental range matters crucially and ineliminably, such that the “meaning” of a gene depends on that context. None of the evo-devo leaders strike me as saying genes are irrelevant (not even, if you read them carefully, the epigenetics folks); merely that as the so-called Parity Thesis has it, genes are first among equals (prima inter pares) in the developmental resources on which evolution acts.

    I look forward to reading the rebuttal.

  7. #7 Mark Blumberg
    February 14, 2009

    Here is my response to Jerry Coyne’s review, just published in Nature:

    http://www.psychology.uiowa.edu/Faculty/Blumberg/Reprints/Freaks.NatureResponse.pdf