In tomorrow's New York Times, I take a look at the evolution of intelligence. Or rather, I look at its flip side. Scientists and the rest of us are obsessed with intelligence--not just the intelligence of our own species, but any glimmer of intelligence in other animals. I've written plenty of stories myself on this research, from the social brilliance of hyenas to the foresight of birds. But if these faculties are so great, then why aren't more animals smart? The answer, experiments suggest, is that learning and memory have nasty side-effects. They can even shorten your life (at least if you're a fly). This story has an odd back-story of its own. If you report on scientific research on evolution, sooner or later you'll find yourself reading mind-blowing distortions of the science produced by creationists and people who make the same sorts of distortions and really really really don't want to be called creationists. Sometimes they happen to choose some interesting research to distort, which, for me, is the silver lining in gloomy creationist clouds. A couple years ago I discovered to my surprise that Ann Coulter devoted several pages in one of her books to misreading an article of mine about the appendix. Coulter couldn't seem to understand that despite natural selection's ability to produce adaptations, nature is filled with flaws (like my own defective appendix). One source of nature's imperfection is the inescapable trade-off between the benefits some traits provide and the costs they incur. Coulter scoffed at experiments that suggested natural selection might not favor smart fruit flies. At about that point, I decided I had enough of Coulter and tracked down the original studies. I've been following this fascinating line of research ever since.