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Haeckel, Ernst (1834–1919) German Evolutionary biologist
Ernst Heinrich Philipp August Haeckel is best known as
the principal champion for Darwinian evolution in late 19thcentury
continental Europe, and for evolutionary concepts
that turned out to be wrong in their original form.
Born February 16, 1834, Ernst Haeckel was a physician
but in 1859, upon reading Darwin’s book (see Darwin,
Charles; origin of species [book]), he abandoned his practice.
He studied zoology at the University of Jena, then became
a professor of comparative anatomy at that university in 1862.
He extensively studied the embryology of invertebrates (see
invertebrates, evolution of) and a group of protists (see
eukaryotes, evolution of) known as radiolarians.
Although Haeckel defended evolution, he like many
other prominent scientists did not agree with Darwin that
natural selection was the mechanism of evolution. In
particular, Haeckel and many other scientists accepted a version
of Lamarckism. He also believed that evolution had a
predetermined direction. This direction was not impelled by
spiritual forces—as many other German scholars believed,
following the tradition of the scientist and writer Johann
Wolfgang von Goethe—but by natural law. This direction
could be glimpsed in the stages of development of an animal’s
embryo. As Haeckel described it in a still famous quote,
“Ontogeny recapitulates phylogeny.” This means that an animal’s
embryo, as it develops, passes through the same evolutionary
stages by which its species evolved. Thus the human
embryo goes through fish, amphibian, reptile, and earlier
mammalian stages, according to Haeckel’s interpretation.
While evolutionary biologists still accept this overall pattern,
it is considered an effect rather than a cause, and they do not
accept it as a natural law (see recapitulation). The figures
that Haeckel published, illustrating stages of embryonic
development, contained errors. In particular, Haeckel used
dog embryos to fill in some missing stages in human embryonic
development. The differences were minor and did not
alter the overall pattern but tarnished Haeckel’s reputation
H
among evolutionary scientists. He remained popular with the
reading public.
Haeckel also championed eugenics. He stated that “Politics
is applied biology,” by which he meant that evolution
led upward toward white Europeans and that politics should
advance the social and biological interests of white Europeans.
After Haeckel’s death, the Nazis used this quote and his
justifications for racism, nationalism, and social Darwinism
to support their cause.
Haeckel applied his scientific concepts broadly, as an
amateur scholar in anthropology, psychology, and cosmology.
He used evolution as the basis for attacking religious
views. He could be considered the German counterpart of T.
H. Huxley (see Huxley, Thomas Henry) but without Huxley’s
rigorous regard for facts. Haeckel died August 8, 1919.
Further Reading
Gasman, D. The Scientific Origins of National Socialism: Social Darwinism
in Ernst Haeckel and the German Monist League. London:
MacDonald, 1972.
Museum of Paleontology, University of California, Berkeley. “Ernst
Haeckel (1834–1919).” Available online. URL: http://www.ucmp.
berkeley.edu/history/haeckel.html. Accessed April 28, 2005.
Haldane, J. B. S. (1892–1964) British Zoologist John
Burdon Sanderson Haldane was an idiosyncratic genius who
contributed to the modern understanding of evolution in several
important ways. His father, John Scott Haldane, was a
professor of physiology at Oxford University, whose diverse
studies included parasites, heatstroke, and altitude sickness. J.
S. Haldane also studied the intervals that were necessary during
an ascent from deep diving in order to avoid the bends. A
fearless researcher, J. S. Haldane even took notes on his symptoms
while mildly poisoning himself with carbon monoxide.
Born November 5, 1892, J. B. S. Haldane worked alongside
his father, J. S. Haldane, and conducted his own experiments,
even in childhood. As a teenager, he bred guinea pigs