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
Leopard (pattern) insects such as the giant leopard moth, and fish species such as the leopard darter, leopard shark, and the leopard eel. Examples of plants that use the term include the leopard lily, and the leopard flower. The "Lp" (leopard complex) gene is responsible for the leopard color pattern in horses, which not only produces a spotted coat color but also causes mottling of the skin, a white sclera around the eye, and striped hooves. Horses with the "Lp" gene may be spotted all over, or may have concentrations of spots in various patterns. Leopard (pattern) A leopard pattern is a