Vogel Steven. Cats' Paws and Catapults: Mechanical Worlds of Nature and People

New York: W.W. Norton & Company, 1998. — 382 p. — ISBN: 0-393-04641-9.Nature and humans build their devices with the same earthly materials and use them in the same air and water, pulled by the same gravity. Why, then, do their designs diverge so sharply? Humans, for instance, love right angles, while nature's angles are rarely right and usually rounded. Our technology goes around on wheels―and on rotating pulleys, gears, shafts, and cams―yet in nature only the tiny propellers of bacteria spin as true wheels. Our hinges turn because hard parts slide around each other, whereas nature's hinges (a rabbit's ear, for example) more often swing by bending flexible materials. In this marvelously surprising, witty book, Steven Vogel compares these two mechanical worlds, introduces the reader to his field of biomechanics, and explains how the nexus of physical law, size, and convenience of construction determine the designs of both people and nature.Noncoincident Worlds
Two Schools of Design
The Matter of Magnitude
Surfaces, Angles, and Corners
The Stiff and the Soft
Two Routes to Rigidity
Pulling versus Pushing
Engines for the Mechanical Worlds
Putting Engines to Work
About Pumps, Jets, and Ships
Making Widgets
Copying, in Retrospect
Copying, Present and Prospective
Contrasts, Convergences, and ConsequencesNotes