Clockwork homeostasis?

The comment thread on Denyse O’Leary’s review of Purpose and Desire at MercatorNet is rich with interesting fodder for discussion. One of the commenters there, Hrafn, has been highly critical of the book, and has staunchly defended his (her?) position. I think he (she?) is wrong on several fronts (no surprise there), but I respect the spirited argument. Argument is what moves us forward. Argument is what I hope the book will prompt. And by argument, I don’t mean argument like one finds in the argument clinic, which sadly seems to characterize much of the discussion over Darwinism and its alternatives.

One of Hrafn’s comments is noteworthy, concerning the evolution of homeostasis:

“It is trivially easy to find a large scientific literature supporting the evolution of homeostatic systems (e.g. The evolutionary basis of thermoregulation and exercise performance, Marino FE, Med Sport Sci. 2008;53:1-13.)”

Hrafn’s intent was to discredit my claim that homeostasis is a fundamental property of life that, among other things, makes evolution an intention-driven phenomenon. Not, by implication, a gene-selection-driven phenomenon. That certainly is a discussion-worthy point (the reason I wrote the book), because the prevailing view is that homeostasis exists because of selection for homeostasis-specifying genes. This view, I argue in Purpose and Desire, has it exactly backwards. The mechanisms of homeostasis—the ‘clockwork homeostasis’, I call it—are the outcome and not the cause of this fundamental property of life.

Hrafn’s reference to the trivially-easy-to-find literature contradicting my argument caught my interest because the evolution of homeostasis of body temperature occupied an entire chapter of Purpose and Desire. The problem of thermal homeostasis was also a significant focus of my early research career. So, I was curious what this trivially-easy-to-find paper said. So, I looked it up.

It was not exactly trivially easy to find. The journal in question (Medicine and Sport Science) was not in any of my university’s journal databases, which are pretty good. Nevertheless, I did manage to obtain a copy through my library’s interlibrary loan system, which is also very good.

Frank Marino’s paper is about the evolution of thermoregulation in humans as it might inform our understanding of heat balance issues in athletic performance, particularly in the defense of brain temperature. I have a few quibbles with the rather broad-brush approach to “evolution” that Marino takes. He starts with the primordial soup (the relevance of that is …?), he assumes that all mammals are strong thermoregulators (they are not), and does not write at all about behavioral thermoregulation (which is especially problematic for the clockwork homeostasis idea). Nevertheless, I applaud his attempt to bring evolutionary thinking to a field where it is sparse, and the rest of Marino’s paper is much better meeting that goal.

One passage, in a section headed “Bipedalism and Teleo-Anticipation” goes right to Hrafn’s point. By teleo-anticipation, Marino means the continual anticipation of future effort to adjust thermoregulatory mechanisms in pursuit of an end-point: a goal. And here is what Marino had to say about that:

“Although there is very little empirical evidence for such an anticipatory strategy being used by early hominids, there can be no other interpretation of the retrospective analysis of the available evidence when considering the environmental challenges faced by early hominids. [It] is possible to speculate that this anticipatory or teleological ability was indeed used by early hominids … ” [emphasis mine]

It seems that Marino is quite emphatic that the evolution of human thermoregulation cannot be explained without purposefulness. This is the very point I make in Purpose and Desire. And it seems to directly contradict Hrafn’s interpretation of it.

Which comes back again to the main point of Purpose and Desire: Is it possible to have a coherent theory of life and evolution without including purposeful mind into the models? I say no. Frank Marino seems to say no as well.

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