Similar Discovery Phenomenon
Findings like this give me goose bumps. It almost makes the concept of innovation (as we tend to see it) null and void, and stresses the extent to which ideas are a product of their environment.
The pages of the history of science record thousands of instances of similar discoveries having been made by scientists working independently of one another. Sometimes the discoveries are simultaneous or almost so; sometimes a scientist will make anew a discovery which, unknown to him, somebody else had made years before.
Such occurrences suggest that discoveries become virtually inevitable when prerequisite kinds of knowledge and tools accumulate in man's cultural store and when the attention of an appreciable number of investigators becomes focused on a problem, by emerging social needs, by developments internal to the science, or by both.
The sheer fact that multiple discoveries are made by scientists working independently of one another testifies to the fact that, though remote in space, they are responding to much the same social and intellectual forces that impinge upon them all.
Source: Excerpts from "Resistance to the Systematic Study of Multiple Discoveries in Science" by Robert Merton. Eur. J. Sociol. 4:237-82, 1963. Full report available here.