Turned up to eleven: Fair and Balanced

Wednesday, June 05, 2002

Yesterday, I breathetakingly (sp?) asserted that human beings seek patterns, both spatially and temporally, and that this creates and inhabits many of the controversies over scientific findings and efforts to understand humanity's origins, essence, and raison d'etre. In any event, I thought that for the purposes of finishing this perhaps not too interesting thread, I can tie this to how people in general talk about Evolution.

"Godless Capitalist", who interestingly, has joined a not-for-profit communal blog (all blogging has to be construed as volunteer work, as far as I am concerned), will be pissed at me for saying this, but Stephen Jay Gould has had some very interesting things to say about Evolution in public debate and policy determinations, in particular about the "narrative" aspects of Evolution (I am sure he is not the only one who said these things, but his books are ones I have read). In particular, in his collection "Full House", Gould discusses the pervasive notion of "Evolution as progress". We use the word evolution commonly to describe things progressing along an axis of increased sophistication or utility. For example, we might discuss the "evolution" of the automobile, from the Model T to the Jaguar X-type (just an example, don't write me long comments about how the XK-8 is much better, I don't care), but this is really very misleading. Technological evolution is, actually, driven by a form of selection (customer preferences), but it is largely driven by advances in engineering that are directed, by the ingenuity and creativity of automotive engineers. Biological evolution, on the other hand, is undirected. Further, human beings, in their interactions with technology, tend to abandon old tech in favor of new tech (perhaps some engineer can give me a counterexample, but I think this holds), and not be bound by old designs when formulating new ideas. This is a critical difference. An organism that needs to improve its swimming ability can't change its bone structure and shape in one generation. Only small changes are possible at any given stage (in physiological terms).

I want to expand on this, because it is very important. Biology is undirected. That means that there is no engineer looking at the design, saying "you know, those eyes would be a lot more useful if they could see in the UV range." Changes occur by several distinct, defined mechanisms (sexual reproduction, recombination, point mutation, horizontal DNA transfer), in a random fashion. Natural selection, with its many differential selection pressures, acts on the phenotypes of the individuals, and optimizes, over long time scales, those phenotypes for life under a given set of conditions. This model is deeply complicated by the fact that conditions change, sometimes on shorter time scales than organisms change. Keep that in mind.

Finally, technological evolution is less niche driven, and more driven by general demands of an entire populace. Although there are certainly those who want minivans, those who want sports cars, those who want luxury sedans, and those who want trucks, there is a general, underlying need for a mode of transportation that is 1)fast, 2)inexpensive, and 3)adaptable. In biological evolution, while the overall common goal of survival and reproduction is present, the mechanisms can be extremely different. Microbes living at deep sea vents using inorganic chemicals (sulfur, nitrogen and iron, primarily) to obtain energy are incredibly different from a cactus using solar energy to grow. They have very, very little in common.

Getting back (finally!) to my original point, humans seek to build a narrative out of this historical record of evolution, and we often imbue that record with "progress". There are some ways in which this is reasonable, for example, it is certainly true that the Earth has progressed, over time, from a planet containing exactly one life form to one containing a frighteningly huge amount of biomass. It is not true, however, that life has "progressed" from single celled to multi-cellular. I believe it was T.H. Huxley who noted that God must "have an inordinate fondness for beetles" (google fact check of myself, it was JBS Haldane), but in reality, God must have an inordinate fondness for bacteria, because prokaryotic organisms are by far the dominant organisms on Earth, by any measure (numbers or biomass), inhabiting essentially every conceivable niche for life to exist in. The "evolutionary bush"(no dirty jokes, please!), is a much better metaphor (tree of life isn't bad, either), because by any reasonable standard, the path of life on earth has been diversification into many, many niches, occasionally marked by catastrophic extinction events, followed by more diversification.

So, why does all this cause problems? Essentially (warning, obvious point ahead!), Evolution has been interpreted as a competing "origins" story with Biblical Genesis (forget that Genesis itself contains 3 competing "origins" stories), and also with disrupting humanity's place as the "chosen" species. This is true, to a large extent, but it fundamentally comes down to the use of scientific methods to determine the answers to questions, rather than mythmaking and oral and written tradition. Evolution creates a fundamentally different narrative about how humanity came to be, and it can be disruptive to people's world views. I think the comparison to gravitation is again apt, but this time going back to Newton's scientific father, Galileo, who used simple observation and calculations (well, simple to us now!) to show that the religious doctrine of the day was at odds with observable reality, and it took many, many years for his work and observations to be understood in the general populace (I believe that the church only recently apologized for its treatment of Galileo). The same is likely to be true for Evolution (although it has been almost 150 years since Origin of Species).