1st column: evolution 2nd column: to the conditions of their labor 3rd column: Plainly, this second species of Man was subterranean. <span>There were three circumstances in particular </span> <span>which made me think that its rare emergence </span> above ground was the outcome of a long-continued <span>underground habit. In the first place, </span> <span>there was the bleached look common </span> <span>in most animals that live largely </span> <span>in the dark—the white fish of the Kentucky caves, for instance</span>
