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Introduction to the Topic
Scientific American recently declared Charles Darwin
to be the most influential scientist of the past millennium.
(The subtitle on the cover was "Sorry, Einstein . . .")
. The volume of material written on Darwin is enormous and continues
to grow. His writings have come to occupy a peculiar niche. While
even most successful scientists' works generally cease to be read
after their ideas have been accepted and absorbed, Darwin's books
are still read today both by scientists and by non-scientists,
and they even continue to be cited with some frequency in scientific
publications. What can account for this continued interest more
than a century and a half after his birth?
Because Darwin's ideas had powerful implications for core issues of origin, identity, and destiny, they naturally reverberated across a wide range of human concerns from their first appearance onward. As we begin a new millennium, there are several issues in the spotlight that are once again strongly linked to Darwin. It is these linkages, and the broader implications of his work in so many areas that, no doubt, enabled Darwin to beat out Einstein in the scientist-of-the-millennium battle. Most notably, the first complete sequencing of a human genome, accomplished earlier this year, opens up a future in which we will know every detail of the physical structures and processes that make us who we are. This detailed knowledge of genetic material, human and non-human, is enabling us to trace inheritance and relatedness across species and between individuals with increasing exactitude. Darwin's fundamental insight that diverse forms of life arise from natural selection, that is, from an ultimately explainable physical process, is thus being extended to one of its crucial terminal points.
As this terminal point is reached, the starting point begins
to be illuminated more and more brightly as well. While as of
today there haven't been any genome-like dramatic breakthroughs,
scientists are edging closer to an understanding of the origins
of life. It is possible, for instance, that in the near future,
an independent, self-replicating life form will be synthesized
in the laboratory. Such experiments, however, as dramatic as
they may be, are unlikely to fully explain life's origin on earth.
The origin of life could in fact be inherently inexplicable. A small, highly vocal minority of scientists argues that the structures and systems that sustain life at the molecular level are too complex to have appeared spontaneously. Because the question of life's origin remains essentially unexplained (though science seems to be getting closer) no one can as yet answer it with complete authority. It therefore has the character of a true mystery-intriguing clues abound, but the denouement is yet to be reached.
Darwin said very little about life's initial appearance in
The Origin of Species. Because the science of his day
could offer so little insight into the issue, he limited himself
to one sentence of speculation, suggesting that all of life may
have sprung from a single source. Life's origin is therefore
a tantalizing question that Darwin could only guess about, but
which may soon be answered-or it may not. In any event, we are
living at an exciting time, when answers to fundamental questions
could appear in tomorrow's headlines.
One of the foremost researchers in the area of life's origin
happens to be a Grinnell graduate, Thomas Cech '70. Dr. Cech,
who received the Nobel Prize in Chemistry in 1996 (?), has generously
agreed to meet with us in a video conference. This video conference
will give us a glimpse into the frontier of this fascinating area
The question of life's origin is closely linked to questions
regarding earth's history, and the history of the solar system.
These lines of inquiry lead, in turn, to questions regarding
the probabilities surrounding life's appearance on earth.
(What were the conditions on earth when life appeared? Given
those conditions, was life's appearance inevitable, or was it
a highly unlikely occurrence?) Recent discoveries of bacterial
life forms in extreme environments deep within the earth's crust,
at extreme temperatures and pressures near deep sea vents, and
in the absence of light and oxygen, have tended to expand the
types of environments deemed suitable for microbial life, and
thus to increase the estimation of life's probability. This
question of life's probability is ultimately unanswerable, however,
without considering the probability of extra-terrestrial life.
While extra-terrestrial life was formerly a fringe issue, it has
thus moved further into the scientific mainstream. NASA has recently
put the search for extra-terrestrial life near the top of its
list of priorities. In the coming years, exploration of the solar
system therefore has the potential of yielding answers in this
On the surface, the search for ET would seem to be very distant from our topic. The linkages that bring us to it are not particularly strained, however. Instead, they are indicative of a newly emerging synthesis in the sciences. In probing the question of life's origin, many areas of science that once were widely separated, such as oceanography, astronomy, molecular biology, geology, astrophysics, archeology (the list continues) are increasingly dependent on one another as they collaborate to create a coherent overall picture of life on earth.
One would think that by now we have listed plenty of evidence
to show that Darwin's impact is wide enough to warrant the millennial
prize, but we've only just started. Darwin's legacy is by no
means limited to the scientific frontiers mentioned thus far;
his ideas also have an impact in social, religious, and philosophical
contexts as well. While Darwin said next to nothing about human
origins in his first book, On the Origin of Species,
he did devote the entirety of his second, larger book (The
Descent of Man, and Selection in Relation to Sex) to the topic.
The central idea of the Origin of Species-that biological
diversity emerged as a result of a gradual process of "natural
selection"-has been widely accepted, the central thrust of
his second book, on the other hand, remains controversial.
To state its point in the most bald terms, The Descent of
Man asserts that the totality of the human organism, its physical
form, as well as its behavior and even its culture, is, like all
of nature on earth, descendant from pre-existent forms as a result
of the processes of natural and sexual selection. Many scientists
who ardently support Darwin's ideas in nature as a whole, at the
same time strongly resist applying his ideas to the area of human
behavior and culture. The complexity of human culture is seen
by them to exist on a different, quasi-independent plane from
the rest of nature. The attempt to extend Darwin's ideas into
the human arena generates mere "just so stories," unsupportable,
unscientific explanations concocted after the fact. Moreover,
such attempts can be dangerous because of the temptation to use
Darwinian explanations to validate one's own interests. The Nazi's
concept of the "master race" was the most insidious
example of this sort of misapplication of Darwin's ideas. Though
the vociferousness of this debate (referred to variously as sociobiology,
evolutionary psychology, or social evolution) has lessened since
its first appearance about thirty years ago, it continues to be
an ongoing controversy.
For sheer longevity, as well as intensity of debate, however,
none of the issues listed thus far can match the conflict between
Darwin's ideas and religion. Individuals with a scientific bent
are tempted to dismiss all religious qualms about Darwin as a
sort of belligerent ignorance. The outrageous claims of extreme
creationists serve to reinforce this perception. At a deeper
level, however, there are religious and philosophical issues raised
by Darwin's thought that cannot be so easily dismissed.
Initially, the strongest barrier to acceptance of Darwin's
ideas was the fear that such acceptance would lead to a collapse
of social and moral order: If God is not in charge, and if a struggle
for existence rules all of nature, then what is to keep human
beings from behaving like brutes? Though this question sounds
simplistic and reactionary, in its essence, it remains unanswered
to the present day. To restate it in less rhetorical terms: if
human behavior is purely a biological construct, what are we then
to use as our ultimate moral compass?
Our stance toward evolution has a strong link not only on our
moral sense, but also on our understanding of human destiny.
The biblical view places humanity in supremacy over nature. While
Darwin's writings presented a new view in which humanity was fully
integrated into nature, he nonetheless frequently employed value-laden
language that placed humanity in a privileged position as the
pinnacle of evolution. This privileged view of humanity is now
seen by many as a vestige of anthropocentrism on Darwin's part.
It is pure hubris to imagine that evolution has proceeded with
humanity as its ultimate goal. Evolution has no ultimate goals,
no foresight, no direction in mind.
The issue of directionality, or "teleology," in evolution
has thus developed into yet another area where opposing camps
hold strong opinions. A literal biblical view, that humanity
has been placed in supremacy over nature, is difficult to support
scientifically. It is possible, however, to argue for directionality
without invoking a divine agent that guides nature. Humanity
may not be the goal of evolution, but there has arguably been
an overall increase in complexity since life appeared some four
billion years ago. Robert Wright, in Non-Zero, published
earlier this year, uses game theory to argue that an inherent
tendency toward cooperation is part of the evolutionary process.
This tendency toward "non-zero-sum" relationships leads,
overall, to ever larger and more complex living entities. The
internet is a natural outgrowth of this tendency, and there is
a sense in which it should be viewed as a living organism. The
opposing camp would argue that all this talk of directionality
is wishful thinking, or just self-serving, delusional anthropocentrism.
Religious belief itself can be threatened by Darwin's ideas. If our religion entails a belief in a God who exists in some way above or outside of nature, and who created the universe-a deistic approach--then our God tends to be pushed further and further to the margins by science: to the very start of life on earth, or to the first instant of the big bang. In this case, science seems to grow while God seems to shrink. Another approach is to view God as immanent in all things. In that case, God regains stature. Still, the dilemma described above continues to lurk about when we try to use nature as a moral guide. If these philosophical battles leave us exhausted, we can negotiate a truce, and take the stance suggested by Stephen Jay Gould, in which we strictly separate religious/moral issues from the scientific/factual ones: science can never dictate morality; religion can't arbitrate questions of fact.
Darwin was rightly chosen as the scientist of the millennium not because he found the ultimate key to unlock nature's mysteries, but because he unlocked a pandora's box, and the gang of spirits that sprang from it continues to fling thorny questions at us of origin, identity, and destiny-where we came from, who we are, where we are going.
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