Tonight I found this article in the New York Times that talks about mismatch:
Regarding proximate vs. ultimate (evolutionary) causation I also want to post a nicely worded quotation from an article by Harris and Malyango, regarding “evolutionary causes for human disease, disorders, malfunctions and apparent design failures”
“To clarify what we mean by evolutionary causes it is useful to make a distinction from a different level of causality in biology, that of proximate causes. Proximate causes are at the level of the immediate mechanisms that give rise to disease, disorders, and malfunctions. These include detailed accounts of physiological processes, embryological development, and anatomical relationships and functions.
Evolutionary explanations, in contrast, are obtained via researchers taking an historical perspective… They look back in time, through lenses of scientifically established evolutionary principles, in order to investigate medical problems and ailments. An evolutionary approach would ask such questions as: “Why hasn’t natural selection eliminated a particular disease?” “Why do our bodies have certain flaws of engineering that make us susceptible to particular medical complications?” “Might certain modern diseases and ailments be the result of a mismatch between our biological heritage and our modern-day lifestyles?” and “Are characteristic physiological responses to disease in fact adaptive defenses that have developed over evolutionary time?”
Harris and Malyango 2005. BMC Medical Education, 5:16