"Ernst Mayr" (2005)

Ernst Mayr

"The Daily Telegraph" 08 Feb 2005

Ernst Mayr, who died on February 3 aged 100, was widely considered to be the
world's most eminent evolutionary biologist, a reputation he earned by
synthesising Darwin's theories of evolution with modern thinking on genetic
inheritance and evidence from fieldwork on animal populations and diversity.
Darwin's theory of natural selection suggested that living creatures
constantly develop minor changes, and that those which develop
characteristics that make them better adapted to their environment are the
ones that survive. Though the theory was generally accepted, Darwin had
offered no coherent account of how these changes occur and how new species
arise.

By the early decades of the last century, some scientists were beginning to
question whether a slow process of accumulated changes could possibly
account for the huge variety of species which exist. In the 1930s, the
leading geneticist Richard Goldschmidt suggested that the creation of new
species came from sudden, wholesale genetic mutations that led to the
emergence of "hopeful monsters", very different from their parents. Those
that were better adapted to their environment survived and became new
species. Those that did not died out.

Mayr, a biologist and curator at the American Museum of Natural History, was
convinced that Goldschmidt's theory was wrong. He had noticed, on field
expeditions to New Guinea and the Solomon Islands, that individual species
of birds tend to occur in small geographic pockets physically separated from
closely related, yet different, species. In a series of articles beginning
in 1940, he argued that new species emerge over long periods in geographic
isolation. In such communities with a limited gene pool, small genetic
mutations accumulate more rapidly, leading to the development of new
populations and eventually to new species no longer capable of interbreeding
with other descendants of their ancestors. Mayr's theory, known as
"allopatric speciation", was widely accepted when it was published in
Systematics and the Origin of Species (1942), and became one of the
foundations for the punctuated equilibrium theory of Niles Eldredge and
Stephen Jay Gould.

The son of a judge, Ernst Walter Mayr was born on July 5 1904 at Kepten,
Bavaria. He began his career as a medical student at Greifswald University,
but his real interest was bird-watching. In 1923, on a lake near his home,
he spotted a pair of red-crested pochards, a species not recorded in central
Europe for 77 years, and was summoned to Berlin to give an account to the
ornithologist Professor Erwin Stresemann, curator of the city's Natural
History Museum.

Stresemann was so impressed by the young man's knowledge of natural history
that he invited him to spend that summer at the museum as a volunteer,
classifying tropical bird specimens. Before he was due to receive his
degree, Stresemann offered to send him to the tropics if he delayed his
medical career and took a doctorate in ornithology. Mayr decided to abandon
his medical studies altogether and completed his doctorate in just 16
months.

In 1927, at a conference in Budapest, Mayr met the zoologist Walter
Rothschild, who was engaged in building up a collection of bird skins at his
private museum at Tring, Hertfordshire. Lord Rothschild was urgently seeking
a new bird collector after the unexpected death of his staff naturalist in
New Guinea. Mayr was hired immediately, and over the following year he
ventured into six unexplored mountain ranges in New Guinea, collecting more
than 3,400 bird skins and discovering 38 new species of orchid.

In 1928 he was invited to lead a collecting expedition to the Solomon
Islands for the American Museum of Natural History. The expedition proved
highly successful, discovering scores of new species and bringing back
enough specimens to fill a new hall. In 1931, Mayr joined the museum as a
research associate in ornithology; a year later, when it acquired Lord
Rothschild's collection of 280,000 bird skins, Mayr was sent over to England
to supervise the shipment of the collection, of which he was subsequently
appointed curator. He took American citizenship in 1932.

Mayr's taxonomic analysis of the Rothschild collection led in 1941 to the
publication of his exhaustive List of New Guinea Birds. In the course of
this work, he became involved in the dispute among biologists about species
differentiation. Traditional Linnaeans defined species identity simply by
physical appearance, but a more modern school of biologists had begun to
rely on genetic makeup. Both methods, as Mayr observed, had drawbacks. His
suggestion in Speciation Phenomena in Birds (1940) that species are groups
of animals that can interbreed and produce offspring quickly won acceptance
as a more objective and logical rule of thumb.

In 1953 Mayr was recruited to Harvard as Professor of Zoology and became
director of the university's Museum of Comparative Zoology in 1960. In this
new environment, he developed a new interest in the history and philosophy
of biology and worked hard to establish the subject as a discipline as
rigorous and important as physics or chemistry.

Although he formally retired in 1975, he did not give up working, and his
later years saw the publication of eight major works. His last book,
published a month after his 100th birthday, was What Makes Biology Unique.
At the time of his death, he was said to be pursuing five lines of
research - one aimed at shattering the creationist doctrine of "intelligent
design".

Mayr received numerous honours for his work, including the Balzan Prize
(1983), the International Prize for Biology (1994), the Crafoord Prize of
the Royal Swedish Academy of Sciences (1999) and the Royal Society's Darwin
Medal (1984).

Ernst Mayr married, in 1935, Margarete Simon, who died in 1990. They had two
daughters.