Bird taxonomy is a difficult field because of the severe anatomical constraints imposed by flight. There are only so many ways to design a bird capable, say, of catching insects in mid-air, with the result that birds of similar habitats tend to have very similar anatomies, whatever their ancestry. For example, American vultures look and behave much like Old World vultures, but biologists have come to realize that the former are related to storks, the latter to hawks, and that their resemblances result from their common lifestyle.
Jared DiamondWhy is it that you white people developed so much cargo and brought it to New Guinea, but we black people had little cargo of our own?
Jared DiamondAll human societies go through fads in which they temporarily either adopt practices of little use or else abandon practices of considerable use.
Jared DiamondWe study the injustices of history for the same reason that we study genocide, and for the same reason that psychologists study the minds of murderers and rapists... to understand how those evil things came about.
Jared Diamond