"Surfaces of and within organisms are curved, most commonly cylindrical ... flat surfaces are less common. By contrast people make load bearing flat surfaces in profusion -- floors, roofs, walls ... Cylindrical elements -- pipes, cans, bicycle frames -- are certainly not scarce but don't dominate."
"Our technology is rife with right angles -- never mind pyramids, it's the 90 deg. angle to which we seem addicted. It appears in almost every door, window, floor tile, box, book pages, many letters of our alphabet, the pockets of my shirt, and on and on. Yet right angles are surprisingly rare among organisms. Tree trunks are generally at right angles to the ground or horizon, but other examples are not easy to find." (Ed.: look closely where a tree trunk enters the ground!)
"We use a few pliant materials -- plastic hinges, elastic bands, rubber pads and so forth; but relative to the abundance of our stiff stuff, soft and stretchy substances are unusual. "
"Our preferred structural materials are most often made of single components above the molecular level, and the values of their properties are the same (isotropic) whatever the direction of measurement -- we mostly use metals and ceramics. Nature's materials are composites, combinations of two or more components, almost always arranged so that the material's mechanical behavior depends on the direction in which they're loaded. "
"Substantial pieces of metal, either pure or alloyed, never occur in nature, even though metallic atoms are crucial to the biochemistry of all organisms... Ours is an overwhelmingly metallic technology ..."
"Both gases and liquids resist being squeezed and thus can be used as structural materials; air and water are the cheapest and most available of substances. ... nature makes elaborate and extensive use of water as a compression resisting material ... but we use it in only a few devices."
"Life may tolerate a reasonable range of ambient temperatures, but organisms are basically isothermal machines rather than heat engines and do their business without depending on large internal differences in temperature. Heat conduction is not a major issue in organisms ... Human technology makes impressively elaborate use of heat conduction bus less of diffusion." Life's Devices
by Steven Vogel, pp. 12-13