“By asking why, by seeking meaning (not in any final sense, but in the immediate sense of use or purpose), Darwin found in his botanical work the strongest evidence for evolution and natural selection. And in doing so, he transformed botany itself from a purely descriptive discipline into an evolutionary science. Botany, indeed, was the first evolutionary science, and Darwin’s botanical work was to lead the way to all the other evolutionary sciences—and to the insight, as Theodosius Dobzhansky put it, that “nothing in biology makes sense except in the light of evolution.”