Cultural and Social Context
The story of Charles Darwin's life is largely the story
of how he discovered and found evidence for his theory of natural
selection. Darwin's life fits a pattern that was
typical for his era in England. He came from a well-established
family of doctors, businessmen, and clergymen. He idled away his
youth, eventually studying for the clergy at Cambridge. He returned
from a long sea voyage, married, and settled in a quiet parsonage
in the English countryside to nurse his health and work on science.
His involvement in the question of evolution, however, makes his
life emblematic of the ideological and cultural struggles going
on around him. Evolution brought several questions of deep religious
and cultural significance to a head. Among the divisive issues
that evolution brought up were questions of how long the world
had existed, whether or not humans were animals, and whether God
was continuously intervening in the world or had created natural
laws to govern it from a distance.
Although the story of evolution is largely one of scientific research
and argument, it is also influenced by the social and cultural
context within which Charles Darwin found himself. The first and
most obvious enabling feature of Darwin's context was the status
of England as an imperial power in the 19th century. With England's
powerful navy and outposts from Tahiti to South America to Africa,
an English ship had more and easier opportunities than any other
nation's to explore the world. The voyage of the Beagle was
actually part of England's empire-building effort. Without it,
Darwin's theory of evolution would never have gotten off the ground.
A second important cultural factor was the changing political and
ideological attitude in England. When Charles attended Cambridge
to study for the clergy, the conservative Tories were in power. While
he was away on the Beagle, the Tories fell from
power and were replaced by a less conservative government that
emphasized freedom of belief and freedom of commerce. The new attitude
of freedom and competition, exemplified by Malthus's theory about the
"struggle for survival," was a foreshadowing of Darwin's own theory
of competition in the natural world.
Intellectual Context
While Darwin is properly credited with making evolution
the dominant paradigm in biology, he was not the first to come
up with the idea. In fact Darwin's major contribution was to suggest
a mechanism for evolution–natural selection–that did not depend
on the intervention of a divine power. There were three major revolutions in
scientific thought that prepared the way for a successful theory
of evolution.
The first major change in scientific thought was in the
field of biology. Linnaeus, the Swedish biologist, had proposed
the first successful taxonomy of all species of plants and animals.
This taxonomy abandoned the theory of the chain of being that claimed
that all living creatures formed and unbroken scale of complexity
and nobility, terminating with the most complex and noble of all,
humanity. Instead, Linnaeus showed that life could be divided into five
separate kingdoms, each divergent from the others.
The rise of evolutionist thinking made the idea of a chain
of being fall out of favor. By the 19th century, it was increasingly
obvious from archaeological research that some species could become extinct
and others could arise, apparently spontaneously. Conservative
thinkers argued that these extinctions and creations were the work
of an active God. However, others argued that there were natural,
non-religious explanations for the extinction and creation of species.
Darwin's own grandfather, Erasmus Darwin, proposed many of the ideas
about evolution for which Charles would later find evidence. In
his Zoonomia, published in two volumes in 1794 and
1796, he described the varieties of life in the world and suggested
that new species arose from the modification of old ones. Although
Charles claimed to have gotten little from Zoonomia, it
is obvious that he read it carefully during his Cambridge years
and it is likely that its passages on evolution influenced him.
The second major change in scientific thought was in the
field of geology. Traditional Christian geologists held that the
catastrophes described in the Bible, such as Noah's flood, had
actually taken place and caused many of the signs of geological
change that could be seen. This view was known as catastrophism.
An alternative to catastrophism was the view called uniformitarianism.
Proponents of uniformitarianism argued that the world's current
geological state was the result of uniform forces working slowly
over long periods of time. Uniformitarianism was one of the foundations
of evolutionary thought, in part because it provided a geological
analogy for biological change: both were the result of gradual
forces working over extremely long time periods. One of the foremost exponents
of uniformitarianism was Charles Lyell, whose Principles
of Geology Darwin read during the voyage of the Beagle.
The third major change in scientific thought was in the
conception of time. Traditional Christian views held that the world
started with its Creation and would end with the second coming
of Jesus. This concept did not give evolution enough time to producing
anything. 6000 years was not enough time to create the incredible diversity
of life in the world. A second way of viewing time was allied with
uniformitarianism; it was that the earth had existed for an extraordinarily
long time, more than long enough for a slow and gradual process
like evolution through natural selection.
Darwin's theory of evolution brought these strands of
thought together into a clear, cohesive argument about how the
competition for life between individuals with varied traits could
lead to near-infinite divergences in biological structure. It helped
bring life further within the realm of science, and today it forms
the conceptual framework within which all of biology is conducted.
