3 The New York Years (1931–1953)

Erwin Stresemann—Teacher and Friend 41
In an appreciation of Stresemann’s influence Mayr (1997l: 853) wrote:
“I was only 12 years old when my father died and in the course of time Stresemann
had become a replacement father figure for me. As the average son would
turn to his father for advice, so I always turned to Stresemann when in need. He
greatly honored me in 1930 (after my return from the expedition) by, so to speak,
moving me up to the rank of the younger brother. [From then on they used the
personal ‘Du’ in German and addressed each other in their numerous letters with
theMalaywords‘adek’(youngerbrother=Mayr)and‘kaka’(olderbrother=Stresemann).]
Yes, there were only 15 years of age difference between us and indeed
I became more and more like his younger brother. Sometimes even to the point
where there were the little competitive jealousies between us as there are between
two brothers. He was my closest friend, indeed I had no other close friend. Yes,
in those years I regularly went into the field with Gottfried Schiermann but this
was an entirely different thing. Stresemann clearly was my closest friend until my
friendship with Dobzhansky developed. For Stresemann I was not only a friend but
even more so a disciple. He was delighted when I was invited to come to New York
and work on the collections because it would mean that his influence would now
begintospreadinAmerica.Inaway,ofcourse,hemusthavebeenslightlyjealous
of the wonderful opportunities which I had in New York, but he never mentioned
it. Fortunately, at least in the early 1930s, he had the Heinrich collections to work
on. It was at this time, particularly in connection with his work on the Aves,thathis
interest shifted from avian species systematics to the morphology and physiology
of birds. With no more collections coming in, such a shift in interest had become
a necessity. I certainly had become his disciple. And virtually all the ideas I had in
the field of systematics I had acquired from Stresemann, including the biological
species concept.”
When Mayr first came to see him in April 1923, Stresemann had immediately
recognized the young student’s scientific abilities and “systematic instinct.” Therefore,
he treated him from the start almost like a colleague sending him long letters
written in a rather leisurely style despite his busy schedule. Mayr became deeply influenced
by Stresemann’s thinking, more by reading his publications than through
discussions. He acquired from Stresemann (and also from Rensch) the principles
of “the new systematics,” including the biological species concept and the model
of allopatric speciation, as well as the ideas of a dynamic faunal zoogeography.
Mayr could not have had a more charismatic, erudite, and scholarly teacher with
wide-ranging interests (including the history of ornithology) than Erwin Stresemann
and they became close personal friends, as Mayr confirmed on a return trip
toNewYorkfromavisittoGermany:
“It is no exaggeration when I say that you are my best friend. Nobody else takes
the trouble to point out to me my mistakes, and nobody knows better than you to
stimulate my imagination and ambitions. I miss such a person in New York now
and bitter experiences must replace my friend’s advice” (6 October 1934; transl.).
Throughout his life Mayr remained grateful to his mentor thanking “his fate that
grantedmetobecomeyourdisciple.Thiswasthebasisonwhichmyentirecareer
rests” (19 November 1946). The publication of Stresemann’s book, Ornithology