Cats' paws and catapults : mechanical worlds of nature and people

Humanoid giants (4 m tall) would be incapable of moving, since doubling the length and width in a proportional manner increases volume and therefore weight by several times, so if such huge creatures exist, either they cannot resemble humans or they are not able to move. This is how the author addresses issues like shape, area and volume as well as their relation to weight. His amusing approach would have made physics a lot more fun at school. He also explains practical matters like "how many books can a standard shelf support without bending and what if you double the lenght..." The author explains supporting structures like skeletons, towers, pillars, etc. and their stability if they rely on 1, 2, 3, 4 or more legs as well as their mobility (motion on ground, motion in water and flight). Probably the main differece between nature design and human engineering is a matter of scale, since the majority of living beings are a lot smaller than humans (the scale is shown in an extremely interesting graph). The author mentions that the main difference when choosing a flying method between an airplane and a bird is size and therefore weight, since weight multiplies faster than area. This is why an airplane requires a lot more flight speed. This section is extremely interesting, I will probably read it again. Other chapters deal with pumps, valves, motors, engines and propulsion systems. I must say that reading through this section was quite difficult, some notions in mechanics are probably helpful. In the end I could manage to understand them after a second reading of some paragraphs (at least the basic concepts or underlying principles, though not the mechanics of the engines itself). This was the only thing that made the book a bit less enjoyable to me. Finally, the author explains the materials preferred by nature and by the human engineer, as well as their properties (metals as opposed to compound materials like wood, bone, cartilage, etc.). He explains flexibility, rigidity, strength, etc. he basically explains how all this materials react differently to tension, pressure, weight, heat, etc. Metals for example tend to create more heat by friction than natural materials, so cooling systems are an essential part of human made engines. "Full of ideas and well-explained principles that will bring new understanding of everyday things to both scientists and non-scientists alike."R. McNeill Alexander, Nature 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 wheelsand on rotating pulleys, gears, shafts, and camsyet 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."This elegant comparison of human and biological technology will forever change the way you look at each."Michael LaBarbera, American Scientist Illustrated "Full of ideas and well-explained principles that will bring new understanding of everyday things to both scientists and non-scientists alike."—R. McNeill Alexander, Nature 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. "This elegant comparison of human and biological technology will forever change the way you look at each."—Michael LaBarbera, American Scientist Our human technology has emerged from ten thousand years of design, trial, and error. Nature's mechanical designs, the function of plants and animals are billions of years older. Both "technologies" share the same physical environment - the same materials, atmosphere, and temperature range - and both are subject to the same gravitational pull. But they've turned out to be wildly dissimilar. Steven Vogel examines the many questions that arise from these differences. Cats' Paws and Catapults is about the ways living things work - and walk, run, jump, and fly - and how they grow. It introduces the reader to the field of biomechanics and explains how the nexus of physical law and historical accident determine the designs of both people and nature. It asks, in the end, how looking at nonhuman - natural - technology might enrich our understanding of what we do and have done. Human technology has taken 10,000 years to develop; natures mechanical designs are billions of years old. Both technologies share the same physical environment but produce vastly different results. Human designers love right angles, but nature is typically rounded and its angles are diverse. We use wheels in numerous ways, yet nature's only true wheels lie in bacteria. We prefer to make surface ships, while nature swims. Our hinges turn because their parts slide, whereas natural hinges (such as a rabbit's ear) turn by bending their flexible materials. This book is about how the ways of living things work and how they grow. It introduces the reader to the field of biomechanics and explains how physical law and historical accident determine the designs of both people and nature. Explores the differences in the mechanical workings of nature and technology and attempts to determine whether the designs of nature, such as the functions of animals; or the designs of man, such as the functions of cars; should be viewed as superior Examines The Workings Of Nature's Mechanical Designs And Man's Technology And Compares The Design Similarities And Differences Of Both Human And Natural Technologies When some of us were much younger-for me the late 1940s-we read Flash Gordon every Sunday in the comics.