3 The New York Years (1931–1953)

360 11 History and Philosophy of Biology—Mayr’s Third Synthesis
is the main cause of evolutionary change in species as a whole.” He was aware
of “neutral characters” whose incorporation into the phenotype he explained by
pleiotropy of many genes, and he pioneered the beginning of discussions of the
evolutionofaltruism.
Fisher, Haldane, and Wright were mostly dealing with evolutionary change
as such, that is with the causes and maintenance of adaptedness of populations.
However, they did not have the background to deal with the evolutionary biology
of biodiversity and its origin, geographical variation and speciation (“It was
the major contribution of the naturalists to have brought the evolution of biodiversity
into the evolutionary synthesis;” Mayr 1992f, p. 181). Another evolutionary
cause relatively neglected by Haldane and most other evolutionists in those
decades was sexual selection. However, on the whole, Haldane’s interpretation
of evolution was very sound. In his arguments against creationism, he pointed
out the frequency of extinction, and the frequency and awfulness of parasitism.
In his essay on Daedalus (1923) the young Haldane presented a view into the
future and discussed some of his deepest beliefs and hopes (Mayr 1995d). He
was optimistic about a better future for mankind and was convinced that science,
particularly the science of biology, would lead us to this desired goal. For Haldane
science was “an endless frontier.” He realized that conventional sources of
energy, like oil and gas, are limited and predicted that other sources, like wind
and sun light, will be utilized increasingly in the future. He also prophesied the
shift from agricultural to an almost completely industrialized society; mankind
will be completely urbanized, he thought. He was convinced that “the centre of
scientific interest lies in biology” and discussed eugenics. Mayr (l.c.) believed that
in our days, Haldane would have been less optimistic in view of overpopulation,
pollution, destruction of the environment, and other reasons. He would have been
pleased to see that biology had indeed become the queen of sciences, as he had
predicted, especially in view of the spectacular achievements of molecular biology.
He would have thought a good deal about developments relating to human
health, particularly the study of human nutrition, one of the most neglected fields
of preventive medicine.
Philosophy of Biology
Mayr’s interest in philosophy also goes back to his youth. In his father’s library,
philosophical titles filled several shelves and he always referred to philosophy
with great respect. Discussions with fellow students in Greifswald in 1924 often
concerned philosophical topics. One of Mayr’s notebooks of those years contains
the following passage which refers to himself (transl.):
“The more he thought about the problem of the position of man in nature the
more he saw that there is only one solution: Man and animals form one unit! This
is the absolutely necessary consequence of all biological laws and knowledge. Thus
he finally had a basis for his worldview” (Weltanschauung).