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42 2 The Budding Scientist
from Aristotle to the Present (1951, 1975) made him “again proud to be your
disciple” (5 August 1951) and “This again gives me an occasion to say how much
I owe you in this respect. I would hardly have been able to do so much if I wouldn’t
have had your standard always in front of my eyes. It is so much easier to be
lazy!” (18 July 1964, transl.). Conversely, Erwin Stresemann followed with great
delight Mayr’s brilliant career in the United States. When the latter assumed the
directorship of the MCZ at Harvard University, Stresemann wrote: “We are very
gladwithyouthatyoualreadyclimbedupagainanothersteponthesteepladderof
your successes and that you now sit where once Alexander Agassiz, Tom Barbour
and other men of their caliber had been enthroned” (22 April 1961; transl.).
The line of influence went not always from the older to the younger partner.
When Stresemann had arrived at an interpretation of polymorphism in wheatears
conflicting with current genetic explanations, Mayr invited him to become coauthor
of a paper on polymorphism in Oenanthe (Mayr and Stresemann 1950)
compatible with genetic conceptions. This, so to speak, gave Stresemann an opportunity
to revise his earlier incorrect explanation. He was an orthodox Darwinist
and acknowledged the importance of natural selection. He felt, however, as did
most other German evolutionists of the time, that this mechanism was insufficient
to explain the origin of complex adaptive structures. Until the end of his life he
was searching for an additional evolutionary “factor X” (Haffer et al. 2000).
Their extensive correspondence from 1923 until Stresemann’s death in 1972
consisting of about 850 letters documents the strong emotional bond between
them, it demonstrates the way in which this bond grew stronger over several
decades, how it withstood difficulties and temptations and thus became a beautiful
testimony of the friendship between two scientists. Beyond their scientific contents
and historical significance these letters have in part literary qualities of a culture
of communication which, compared to our age of telefax and e-mail messages,
already seems to belong to another time (Haffer 1997b, 2007b).
Erwin Stresemann is relatively little known in English-speaking countries, becausehepublishedmostofhisbooksandjournalarticlesinGerman.Thetopinternational
ornithologists knew his Aves volume (1927–1934) and his decisive influenceontheadvancedmoderncontentsoftheJournal
für Ornithologie.Theyelected
him as President of the International Ornithological Congress in 1930, when he was
only 40 years old. The English translation of his excellent book, Ornithology from
Aristotle to the Present (1975) eventually made his name more widely known internationally,
at least among historically interested ornithologists. Stresemann was
one of the key figures of ornithology who, from 1921 onward, merged systematic
ornithology and field natural history in the New Avian Ornithology (Haffer 2007a).
Assistant Curator at the Museum of Natural History in Berlin
As a general museum assistant Mayr, like the three other assistants, was assigned
special tasks. His assignment was the Museum’s main library where he decided
which books to buy, how to classify them, which departments should get incoming