How the Snake Lost Its Legs the butterfly, the snake, and the cheetah. Each consists of three to eight sections named in the style of Rudyard Kipling's "Just So Stories", with titles like "How the butterfly got its spots" or "How the snake elongated its body", though a couple of sections use "Why?" rather than "How?", as in "Why the fly twirls his penis" (it rotates during embryonic development under the control of different genes). In these chapters, Held explains the mechanics of evolutionary developmental biology, complete with accounts of what genes such as hox, hedgehog, and engrailed do to shape bodies. The third part is
The Wind (poem) similar use is made of the letters R, S, D, and finally H. Dafydd took this poetic device, known as "cymeriad", from the older poetic form of "awdl", a kind of poem much used by court poets of the preceding centuries for poems of praise addressed to their patrons. He employed it in several of his "cywyddau". "The Wind" is cast in a form closely associated with Dafydd, the poem in which a messenger or "llatai", usually a bird or animal, is sent to the poet's lover. It is a good example of how Dafydd's works in this form can