Cat's Paws and Catapults: Mechanical Worlds of Nature and People
Fisher, Cary, ASEE Prism
Cat's Paws and Catapults: Mechanical Worlds of Nature and People By Steven Vogel. W.W. Norton; 1998; 382 pp., $27.50.
Reviewed by Cary Fisher
In Cat's Paws and Catapults, Steven Vogel has done an exceptional job of making connections between biology and mechanics, and between nature and technology. His endnotes and extensive reference section combine to make this book both authoritative and an easy read. I have already used some of his examples in my freshman mechanics classes.
Vogel, a Duke University zoology professor, postulates that engineers are as curious about biology as biologists are about our world of manmade technology, asking questions such as: Is nature a good designer? Can we learn (have we learned?) useful design tips from flowers, or from fish?
In Chapter 2, Two Schools of Design, Vogel captures the essential difference between the worlds of biological and engineering design:
Almost anything starts from a plan, whether a blueprint, template, some macromolecular chemical code, or just a scheme held in the mind. But no plan is without antecedent, whether in an individual's mysterious alchemy of experience or as a result of innumerable ancestral adjustments. And neither human nor natural technology represents a single act of creation. But nowhere do they diverge more than in how their plans originate, in the process we call design.
Vogel identifies nature's design process as evolution by natural selection, as contrasted with engineering design loosely based on invention, discovery, development, or planning. He illustrates the severe constraints in evolutionary "design" by focusing on the fact that every organism must grow without loss of function:
Nature, in effect, must transmute a motorcycle into an automobile while providing continuous transportation. …