THE POWERFUL PRIMATE

A biomechanics scholar examines the history of humankind from the vantage point of evolving technology.

Borrowing a page from Vaclav Smil, Ennos examines our species’ development of bodily extensions—atlatl, bow and arrow, steam engine, and so forth—that enabled us to harness ever greater amounts of power and leverage them in war and peace. Ennos begins at the beginning, literally: An early case study is the protohominid discovery that one could use a rock—a “percussion tool,” that is—to break open nuts, a discovery that leveraged the budding human development of muscles of “contractile force.” Soon enough, those ancestors came up with the “Swiss Army knife” of lithics, the hand ax, which could be used to make other tools as well as cut and hammer at things. But why use muscles when a nutcracker can take care of the job? Ennos’ history moves on to the development of tools, some astonishingly simple: “most notably sticks,” one of the “long cylindrical tools” used in everything from warfare to manufacturing and agriculture. But some tools, too, were complex to begin with and have gotten more complex ever since. Consider, as Ennos does, the history of metallurgy, which eventually begat artillery, huge waterproof ship hulls and boilers that “drove huge paddle wheels and propellers,” and on down to cell phones. Ennos isn’t uncritical: He notes, for example, that James Watt’s vaunted steam engine “had a miserably low efficiency of just 2 percent.” And he is quick to point out examples of overreach, a case in point being the overly heavy irrigation of Mesopotamian farmlands with saline water in antiquity, “possibly the first example of a man-made environmental disaster in history.” We continue that path of overreach at our peril, Ennos warns, though it won’t stop our propensity “to wreak devastation on the planet.”

A nimble, wide-ranging history of homo faber, skillful man.