HOW THE LEOPARD CHANGED ITS SPOTS

The Evolution of Complexity

Brian Goodwin

London, 1994.


There is much to learn from this book, whose main concern is with morphogenesis, the development of form in organisms. Many exciting new ideas and findings are discussed, in well-illustrated chapters on "Life, an excitable medium", and so forth.

The final part of the book draws conclusions about renewing biology and our conception of health, which are thoughtful and progressive. However, there are some very peculiar things going on when (neo-)Darwinism is mentioned.

According to Goodwin,

"A striking paradox that has emerged from Darwin's way of approaching biological questions is that organisms, which he took to be primary examples of living nature, have faded away to the point where they no longer exist as fundamental and irreducible units of life." (p.1)
"They have succumbed to the onslaught of an overwhelming molecular reductionism." (p.2)

What sort of thing has Dawkins been saying?

"however complex and intricate the organism may be, however much we may agree that the organism is a unit of function, I still think it is misleading to call it a unit of selection... I am not trying to belittle the importance of the individual phenotype in evolution. I am merely trying to sort out exactly what its role is." (The Extended Phenotype (EP) p.114)

It seems that Goodwin is indulging in a bit of creationism, in the form of a straw man. Here we find him saying that, because evolution is explained in terms of genes,

"This leads naturally and inevitably to the conclusion that, to understand everything that is essential about organisms, what we need to know is the information in their genes." (p.2)

Then what?

"A vivid metaphor for the evolutionary process then follows: organisms are constantly striving to climb up to the higher peaks in the fitness landscape that represent the various possibilities for survival." (p.156)

So that's what Dawkins and his cronies are saying? Well, no. Dawkins explicitly warns us about such a metaphor:

"Neither individuals nor genes really strive to maximize anything. Or rather, individuals may strive for something, but it will be a morsel of food, an attractive female, or a desirable territory, not inclusive fitness. To the extent that it is useful for us to think of individuals working as if to maximize fitness, we may, with precisely the same licence, think of genes as if they were striving to maximize their survival." (EP p.189)

Goodwin announces he has detected 3 main inconsistencies in neo-Darwinism. Taking a quote from Delisi as representative of this theory, he insists that,

"[the] instructions, which define a genetic program, can determine the molecular composition of a developing organism at any moment in its development, but it [- change of subject to the program -] is insufficient to explain the processes that lead to a heart... or any other organ of the body." (p.33)

Dawkins writes:

"Selective theories of adaptation... can cope with the fact that the relationship between a gene and its phenotypic effect is not an intrinsic property of the gene, but a property of the forward developmental consequences of the gene when interacting with the consequences of many other genes and many external factors." (EP p.176)

Goodwin's second point is that,

"The DNA of an organism is not self-replicating; it is not an independent 'replicator'. The only way in which the DNA can be accurately and completely replicated is within the context of a dividing cell." (p.34)

Is this a rebuff for Dawkins?

"The... view of life which this book advocates lays stress on the genetic replicator as a fundamental unit of explanation... But I am not of course suggesting that small genetic units work in isolation from each other, any more than a chemist thinks that atoms do. Like atoms, genes are highly gregarious. They are often strung together along chromosomes, chromosomes are wrapped up in groups in nuclear membranes, enveloped in cytoplasm and enclosed in cell membranes." (EP p.113)

Further down the same page (p.34), Goodwin goes on to say,

"In order for evolution of complexity to occur DNA has to be within a cellular context; the whole system evolves as a reproducing unit."

But this seems very confused: what unit is doing the evolving? The cell? We know that cells reproduce, and DNA replicates, but surely it's the species that does the evolving? After accusing neo-Darwinists of replacing the organism with the gene, he then replaces the species with the cell.

The third issue concerns Weismann's barrier, the idea that genetic instructions are cellular one-way traffic: characteristics cannot be acquired by the organism and somehow encoded into its genes. There is no avenue or mechanism for such a process. This is why Lamarckism is out, and it is a fundamental principle of neo-Darwinism. Goodwin suggests that there is experimental evidence (John Cairns) that bacteria and yeasts can change their DNA "in a directed, adaptive manner". Although this does not seem to be established, Goodwin concludes that Weismannism is incorrect.

I must stop somewhere, and I will conclude with remarks about Goodwin's persistent concern with metaphors. In a bizarre passage early in the book, he sums up Darwinism, then lists some bits of Christian dogma, and simply states that they are similar sets of metaphors. Then we have, directly, this remarkable inference:

"So we see that the Darwinism described by Dawkins... has its metaphorical roots in one of our deepest cultural myths, the story of the fall and redemption of humanity." (p.30)

He picks up this fancy again towards the end of the book:

"If interactions between organisms are to be understood primarily in terms of conflict and competition, manifestations of selfish genes, then our relationships with other species are naturally those of a dominant species and our instinct will be to subdue and control them, even to extinction. However, this view of life reflects a perspective on evolution that is deeply influenced by our cultural myth of the fall and redemption." (p.191)

As proved on p.30? If life is selfish in this way, not just understood to be, and if "our instinct" cannot be opposed, then the grim consequences may follow. Whether or not life is really like that does not seem to have much to do with whether our view of it has some metaphorical kinship with the fall. How he knows these mysterious things is not explained.

Perhaps what we have here is "Brian Goodwin, an excitable medium"?



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Paul Taylor 2001