"The last word in ignorance is the man who
says of an animal or a plant: 'what good is it?' If the land mechanism
as a whole is good, then every part is good, whether we understand
it or not. If the biota, in the course of eons, has built something
that we like but do not understand, then who but a fool would
discard seemingly useless parts? To keep every cog and wheel is
the first precaution of intelligent tinkering."
--Aldo Leopold, A Sand County Almanac