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244 6 Life in North America during World War II
away from New York City. Dobzhansky left for Brazil in early 1943 on short notice.
Therefore, cooperation began in 1944 continuing until 1946. The Mayrs usually
spent about two months in Cold Spring Harbor each year. He would commute to
his office in New York, but at least one month was vacation. The results of Mayr’s
experimental work on isolating mechanisms in Drosophila during these years have
been discussed above (p. 228). Natural history observations which Mayr made in
the outdoors included a song sparrow that went every day to an ant nest to ant
himself (Mayr 1948f); yucca moth larvae which remained in the yucca “fruit” until
there was a heavy rain. Then at once they bored themselves free, dropped to the
soft, wet ground and dug themselves in to pupate. Other observations concerned
the species of insects found in CSH mushrooms and photic signaling of fireflies.
Mayr was also a frequent participant of the annual Cold Spring Harbor Symposia
(1946, 1947, 1950, 1955, 1957, 1959) and presented papers at two of them: 1950
on the Origin and Evolution of Man (where he spoke on “Taxonomic categories in
fossil hominids,” 1951g) and 1959 on Genetics and Twentieth Century Darwinism
(his talk entitled “Where are we?,” 1959f).
For Mayr these summer weeks meant an incredibly important development.
It was there that he acquired his extensive knowledge of advanced genetics and
molecular biology. He had numerous long conversations particularly with Bruce
Wallace during the summer of 1950 who taught Mayr the new genetics of “gene
pools,” “in which the selective value of a gene depended on the genetic environment
rather than on having a constant value. The gene pool had a cohesion, or exhibited
homeostasis” (Provine 2004: 1044). “I not only became a close friend of Max
Delbrück and other leading molecular biologists but also of many foreign visitors,
particularly the ‘French contingent’ (Monod, Lwoff, Jacob, Ephrussi) as well as
others,” like Hershey, Dulbecco, Spassky, and Wallace.
“I had perhaps even more contact with local biologists and saw a great deal
of Barbara McClintock who was rather aloof but quite delighted when a visitor
dropped in once in a while. Dobzhansky’s student Bruce Wallace did very interesting
work in population genetics but, perhaps more importantly, was an even
stronger holist than Dobzhansky. Jim Watson was there for several summers and
became a close friend of my daughter Christa. Indeed I met a large percentage of
the more prominent biologists of the period in Cold Spring Harbor. I never would
have had this opportunity at the American Museum. I have often been asked where
I had acquired my extensive knowledge of molecular biology but the answer is quite
simple: at Cold Spring Harbor.
Whenever new discoveries were made at Cold Spring Harbor or elsewhere, they
very frequently became the subject of heated arguments. I remember when Avery
discovered that nucleic acids were the crucial genetic material, Cold Spring Harbor
was split into two camps. The phage group under the leadership of Delbrück
did not believe it nor did Alfred Mirsky and several others, while another group
consisting of Rollin Hotchkiss, Ernst Caspari, Bruce Wallace, and myself accepted
it rather quickly.”