Mendelian heredity is discontinuous or atomic (in the original sense of not infinitely divisible), like matter and electricity, and unlike time and space. This is parallel to the concepts of digital as opposed to analog operations in computation. The latter can lead to chaos because of the indeterminacy of initial conditions, since on the line of real numbers there is a super-infinity of points. It is known that digital disks and tapes are clearer than analog ones.

So when replicators (RNA and DNA) entered into incipient life forms, they converted the previous protein system from an analog one to a digital one. Replication and reproduction is digital, like iteration in mathematics and in computation. All computers have clocks, as do organisms. Both iteration operations and reproduction consist of discrete steps called generations. Since life is basically a conglomerations of information systems, being digital makes the transmission of messages more clear and distinct. Cycles, like the Krebs cycle of oxidative respiration or the dark reaction of photosynthesis, are also discrete batch processes, although they run continuously like a conveyor belt.

Discrete steps (rises and runs of a staircase) also characterize the “Devil’s staircase”, a fractal “curve” which has no tangent. I prefer to call it the Angel’s Staircase, as in Jacobs dream of a ladder extending to Heaven, with angels ascending and descending. A discontinuous ladder or staircase is better than a continuously sloping ramp. Saltation in the origin of new species is better than continuous gradual evolution from small variations, as in Darwin’s original scheme. .