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Keyboards, Codes and the Search for Optimality

In biology, as in technology, we should not confuse persistence with perfection

Robert L. Dorit

The Early Bird

As evolutionary biologists, we know how to test optimality, even in keyboards. If an optimal keyboard embodies the ideal response to a specific set of challenges imposed both by the machine (avoid the jamming of hammers) and by the users (enhance typing speed and accuracy), we would predict that a significant change in these selective forces would surely change the resulting optimum. Two such tests of keyboard optimality are already underway.

The first test involves the advent of the computer, which has done away with the problem of jamming hammers. Freed from this constraint, the keyboard should, in principle, now be free to evolve to a new optimal design. The second, even more radical experiment is tied to the phenomenon of texting—using handheld devices to type and send written messages. Texting represents a radical shift in the interaction between humans and keyboards: Digits that were previously deemed only suited for pressing the space bar (thumbs) have become central players in communication.

Yet despite these radically changed circumstances, one look at a computer or a handheld device reminds us that the keyboard layout has not changed much since Sholes and Densmore were granted a patent for it in 1878.

August Dvorak's alternate keyboard layoutClick to Enlarge ImageThe persistence of the QWERTY keyboard, and of its related but subtly different counterparts in other languages, testifies to the power of history. The design persists not because it is the best of all possible keyboards, but because it is good enough to do the job. Over time, QWERTY has prevailed because that keyboard has become deeply embedded in the technology of manufacture, in the training of users, and in our muscular and technical consciousness. QWERTY links us, inextricably, to a vast network of mechanical, muscular and symbolic interactions that would make replacing the arrangement of the keyboard—even by a more optimized design—an enormously complex task. Even so, the experiment has been tried. In 1936 a patent was issued for the Dvorak keyboard, a keyboard design that the patent stated to be:

a scientific plan of arranging the keys which will decrease the possibility of typing errors … [It will] increase operating speed by eliminating awkward sequences … lessening the fatigue of the typist, because of fewer interruptions due to errors, because of better arrangement of the keys for typing the sequences most frequently used, and the rhythmical flow of typing induced thereby, and because of more evenly distributed labor for the individual fingers and the two hands.

To be sure, its inventors assumed that the factors that defined the ultimate keyboard could be identified, isolated and optimized. (Nowhere, for instance, do the inventors consider the possibility that errors or operator fatigue might emerge from the alienating character of the typist’s job in the then-emerging machine economy).

The Dvorak keyboard sought to incorporate what was known then about the physiology of muscular action, the ergonomics of the hand, and the frequency of individual letters and of letter pairs in English. Although there is still some question about just how much of an improvement the Dvorak keyboard represented, its layout certainly allowed users to type most common letters without leaving the home (central) row and to alternate hands when typing the most common letter pairs. It was a beautiful attempt to design an optimal keyboard from first principles. But, perhaps most important, it was a layout that arose too late in the game, because 73 years later, the Dvorak keyboard remains the province of the few and the fiercely committed. In engineering, as in biology, optimality seldom trumps history.

If the tensions between the constraints of history and notions of optimality are so apparent in the evolution of a human invention, how do these tensions play out in the evolution of biological features? Technological evolution is, after all, quite different from biological evolution. There are designers and a purpose behind the arrangement of letters on the keyboard; neither drives the evolution of biological features. Nonetheless, the hand of history is clearly visible both in technological and in biological evolution.

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