106 James F. Crow
the time till fixation, and the number of individuals in the path to fixation all were
immediately applicable to the neutral theory. This made the theory quantitative
from the beginning, and permitted many quantitative predictions and tests. It
also provided a rational basis for a molecular clock. Remarkably all this happened
in one lifetime, Kimura’s.
For the rest of his life Kimura devoted most of his energies to finding new
approaches to neutral evolution and defending his theory. Each new molecular
discovery was examined from this point of view, and often was used as an additional
argument. Along the way, he discovered a variety of new mathematical techniques,
useful in evolutionary studies and an important part of the permanent repertoire
of mathematical population genetics. Kimura summarized his theory, and much
more, in a readable book[Kimura, 1983].
4 KIMURA THE MANKimura was widely honored during his lifetime. He received honorary doctorates
from the Universities of Chicago and Wisconsin. In addition, he received 14 other
high awards; some of the most prestigious are foreign membership in the Royal
Society of London and the United States National Academy of Sciences, and the
Darwin Medal of the Royal Society.
He wrote well over 150 major papers and several books. His “The Neutral
Theory of Molecular Evolution”[Kimura, 1983]was favorably reviewed and widely
read. It has become a classic.
While a student, Kimura enjoyed discussing all kinds of subjects: genetics, of
course, but also Greek tragedies, music, and science fiction; he especially liked
Arthur Clarke. He also enjoyed philosophy, especially Bertrand Russell. He and
I had many happy times together, starting with his student days and continuing
through his life. He was a delightful companion.
With scientific colleagues and especially advocates of theories contrary to his,
Kimura was not so gracious. He could be argumentative, petty, and vindictive.
A scientific difference often became personal. In the last decades of his life, de-
fending the neutral theory became an obsession. It was hard to get him to talk
about anything else. This singleness of purpose undoubtedly spurred him to more
research, but it marred his relations with colleagues and other scientists that he
regarded as competitors or opponents. Ironically, the theory stood on its own very
well.
In an earlier period, the best-known geneticist in Japan was Hitoshi Kihara.
After his retirement, Kimura took his position. Now Kimura has taken a place
alongside the great population genetics trinity: R. A. Fisher, J. B. S. Haldane, and
Sewall Wright. For Wright’s final evaluation of the work of all four, see[Wright,
1988 ].