Ch. 9: Searching for Quality
Posted: Thu Feb 16, 2017 11:49 pm
Ch. 9: Searching for Quality
Please use this thread to discuss the above listed chapter of "Darwin's Dangerous Idea: Evolution and the Meanings of Life" by Daniel Dennett.Quality books. Great conversations.
https://www.booktalk.org/
I'm finally getting back into this book and will have to agree with Harry here on several points.Harry Marks wrote:. . . Dennett chose to start out complaining about "some readers' interpretations" of Gould and Lewontin, and then reach some pretty negative conclusions about the work itself without explaining.
It seems to me that Gould and Lewontin are only suggesting that we keep an open mind and to keep looking for other possible adaptive explanations. We have all seen time and again how the real world turns out to be more complex than we had previously imagined. And many biological adaptations have multiple purposes or even change from one use to another over time. This is where the famous reference to spandrels in architecture comes in. But Dennett cites this specific passage and says this:. . . The eskimo face, once depicted as "cold engineered" (Coon, et al., 1950), becomes an adaptation to generate and withstand large masticatory forces (Shea, 1977). We do not attack these newer interpretations; they may all be right. We do wonder, though, whether the failure of one adaptive explanation should always simply inspire a search for another of the same general form, rather than a consideration of alternatives to the proposition that each part is "for" some specific purpose.
You may be scratching your head now, wondering how Dennett could possibly interpret this passage in this way. It seems to me that Dennett is creating a straw man just so that he can attack something. Indeed, take a look at the entire paragraph from Gould’s and Lewontin’s paper:What particularly infuriates Gould and Lewontin, as the passage about the Eskimo face suggests, is the blithe confidence with which adaptionists go about their reverse engineering, always sure that sooner or later they will find the reason why things are as they are, even if it so far eludes them.
So Dennett veers from a thorough, well-reasoned, and truly fascinating argument for adaptionism to this sometimes shrill and poorly argued rant against Gould and Lewontin. Maybe he was trying to inject a little controversy into the book, but he fails to show that Gould is anti adaptionist at all. And I’m not willing to take his word for it.If one adaptive argument fails, try another. Zig-zag commissures of clams and brachiopods, once widely regarded as devices for strengthening the shell, become sieves for restricting particles above a given size (Rudwick, 1964). A suite of external structures (horns, antlers, tusks) once viewed as weapons against predators, become symbols of intra-specific competition among males (Davitashvili, 1961). The eskimo face, once depicted as "cold engineered" (Coon, et al., 1950), becomes an adaptation to generate and withstand large masticatory forces (Shea, 1977). We do not attack these newer interpretations; they may all be right. We do wonder, though, whether the failure of one adaptive explanation should always simply inspire a search for another of the same general form, rather than a consideration of alternatives to the proposition that each part is "for" some specific purpose.