Encyclopedia of Evolution.pdf - Online Reading Center

Eiseley, Loren. Darwin’s Century: Evolution and the Men Who Discovered
It. New York: Doubleday, 1961.
Eldredge, Niles. Darwin: Discovering the Tree of Life. New York:
Norton, 2005.
Healey, Edna. Emma Darwin: The Inspirational Wife of a Genius.
London: Headline, 2001.
Keynes, Richard Darwin. Fossils, Finches, and Fuegians: Darwin’s
Adventures and Discoveries on the Beagle. New York: Oxford
University Press, 2003.
Lamoureux, Denis O. “Theological insights from Charles Darwin.”
Perspectives on Science and Christian Faith 56 (2004): 2–12.
Leff, David. “AboutDarwin.com: Dedicated to the Life and Times of
Charles Darwin.” Available online. URL: http://www.aboutdarwin.
com/index.html. Accessed May 3, 2005.
Moore, James. The Darwin Legend. Grand Rapids, Mich.: Baker
Book House, 1994.
Quammen, David. The Reluctant Mr. Darwin: An Intimate Portrait
of Charles Darwin and the Making of His Theory of Evolution.
New York: Norton, 2006.
Van Wyhe, John, ed. “The writings of Charles Darwin on the Web.”
Available online. URL: http://pages.britishlibrary.net/charles.darwin.
Accessed March 23, 2005.
Darwin, Erasmus (1731–1802) British Physician, Naturalist
Born December 12, 1731, Erasmus Darwin was a prominent
18th-century intellectual. As a physician with wealthy
patrons, he became wealthy, which allowed him the means to
pursue a wide array of studies. He investigated many aspects
of natural history, including botany. He also wrote works of
philosophy and poetry.
In 1794 Erasmus Darwin published Zoonomia, or, The
Laws of Organic Life. This was one of the first formal proposals
of evolution, almost a decade earlier than the French
biologist Lamarck (see Lamarckism). Erasmus Darwin also
expressed his evolutionary ideas in the posthumously published
poem The Temple of Nature, in which he wrote about
the spontaneous origin of life in the oceans, and its development
from microscopic forms into plants and animals:
Nurs’d by warm sun-beams in primeval caves
Organic life began beneath the waves;
First forms minute, unseen by spheric glass,
Move on the mud, or pierce the watery mass;
These, as successive generations bloom,
New powers acquire and larger limbs assume;
Whence countless groups of vegetation spring,
And breathing realms of fin and feet and wing …
Hence without parent by spontaneous birth
Rise the first specks of animated earth.
Erasmus Darwin struggled with the question of how
one species could evolve into another. His explanation was
similar to that of Lamarck, but Erasmus Darwin also wrote
about what we now call competition and sexual selection:
“The final course of this contest among males seems to be,
that the strongest and most active animal should propogate
the species which should thus be improved.” To formulate
his theories, Erasmus Darwin drew upon his extensive observations
of domesticated animals, the behavior of wildlife, and
Darwin’s finches
his knowledge of paleontology, biogeography, classification,
embryology, and anatomy.
Erasmus Darwin died April 18, 1802, before his grandson
Charles Darwin was born (see Darwin, Charles). Erasmus
Darwin’s contribution to Charles Darwin’s intellectual accomplishments
may have been crucial. Charles Darwin, like his
grandfather, integrated knowledge from many fields to reach
his conclusions. Erasmus Darwin’s fearlessness in announcing
an evolutionary theory may have been the stimulus that made
the development of his grandson’s theory possible. Erasmus
Darwin’s fortune contributed significantly to allowing Charles
Darwin to devote all of his time to scientific research.
Further Reading
Browne, Janet. “Botany for gentlemen: Erasmus Darwin and The
Loves of the Plants.” Isis 80 (1989): 593–621.
Desmond, Adrian, and James Moore. “Catch a falling Christian.”
Chap. 1 in Darwin: The Life of a Tormented Evolutionist. New
York: Warner Books, 1991.
Darwin’s finches Darwin’s finches are a group of 14 species
of finches that inhabit the Galápagos Islands off the
coast of Ecuador. The finches, and the islands, are famous
because Charles Darwin (see Darwin, Charles) visited
them in September 1835 during an around-the-world trip on
HMS Beagle. Because evolution is occurring rapidly in these
finches, they represent an almost unique opportunity for
studying evolution in action. Because the species are still differentiating,
some experts classify the finches into a slightly
different set of species than do other experts.
As had every previous visitor, Darwin noticed the giant
tortoises that are unique to the islands. He also observed that
the islands seemed to have similar geography and climate yet
were inhabited by slightly different groups of animals. He collected
specimens of many of the small birds he found. Because
their beaks were all so different from each other, Darwin did
not recognize that the birds were all closely related finches.
When Darwin returned to London, ornithologist John Gould
identified them as different species of finches. Darwin realized
that each island might have had its own species of finch, but
he had not taken careful notes regarding from which island
he had obtained which finch specimen. Fortunately, other
visitors to the islands, including the captain of the Beagle (see
FitzRoy, Robert), had kept more careful notes. When Darwin
published the account of his voyage on HMS Beagle, he
had not yet begun to fully develop an evolutionary theory.
A famous passage indicates that he had already begun thinking
about evolution: “Seeing this gradation and diversity of
structure in one small, intimately related group of birds, one
might really fancy that from an original paucity of birds in
this archipelago, one species had been taken and modified for
different ends.” These finches, then, could be considered the
spark that started the fire of evolutionary theory.
About three million years ago, a group of finches, probably
genus Tiaria, migrated to the Galápagos Islands from the
mainland. From this original founding group, the 14 species
of finches present today evolved (see table). Most of the finch
species live on more than one of the islands, but none live
on all of the islands. No island in the Galápagos archipelago