Part One: The Living Machine

The cell is not a bag of chemicals. It is a factory. It builds, transports, repairs, replicates, and powers itself using machinery whose complexity and coordination have no known explanation in undirected chemistry. Every entry in this section describes a molecular machine documented by biologists, biochemists, and physicists—machines that require all components present and functional simultaneously to perform any function whatsoever. The technical term for this property is irreducible complexity. Its implications for Darwinian gradualism have never been satisfactorily answered.

Chapter 1 — The Gear Nobody Designed

The planthopper nymph (Issus coleoptratus) launches itself in approximately two milliseconds. Both legs must fire within 30 microseconds of each other or the insect tumbles sideways. Nerve pulses are too slow to achieve this coordination. The solution, documented in 2013 by Malcolm Burrows and Gregory Sutton of the University of Cambridge, is a set of interlocking cog gears in the insect's hind legs—the first biological gear system ever documented in a living organism.

The gears are precise. Teeth approximately 30 micrometers high cover a curved strip 400 micrometers long. They interlock with matching teeth on the opposite leg. When one leg begins its jump stroke the gear teeth engage and force the other leg into motion within the required window. The system is mechanical, not neurological. The biological gears solve the coordination problem that nerve signals cannot.

The gear system is irreducibly complex. All components—the teeth, the curved surface, the matching geometry on the opposite leg, the tolerances—must be present and functional simultaneously to produce any coordination benefit. There is no survival advantage to half a gear. A partial gear that does not mesh with the opposite leg produces no synchronization at all. The system either works completely or contributes nothing.

Burrows, M. and Sutton, G.P. "Interacting gears synchronize propulsive leg movements in a jumping insect." Science 341, no. 6151 (September 13, 2013): 1254–1256.