These are excerpts and elaborations from my book "The Nature of Consciousness"
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Design Without a Designer In 1859 Darwin published "The Origin Of
Species". His claim was simple: all existing organisms are the descendants
of simpler ancestors that lived in the distant past, and the main force driving
this evolution is natural selection by the environment. This is possible
because living organisms reproduce and vary (make children that are slightly
different than the parents). Natural selection selects the fittest children,
and the process continues, generation after generation, causing evolution.
Through this process of evolution, organisms acquire characteristics that make
them more "fit" to survive in their environment (or better
"adapted" to their environment). Darwin based his theory of evolution
on some hard facts. The population of every species can potentially grow
exponentially in size. Most populations don't. Resources are limited.
Individuals of all species are unique, each one slightly different from the
other. Such individual differences are passed on to offspring. His conclusion
was that variation (the random production of different individuals) and
selection ("survival of the fittest") are two fundamental features of
life on this planet and that, together, they can account for the evolution of
species. To visualize what is so
special about Darwin's idea, imagine that you
are in a quandary and the situation is very complex. You have two options: 1.
You can spend days analyzing the situation and trying to find the best strategy
to cope with it. Or 2. You can spend only a few minutes listing ten strategies,
which are more or less random and all different one from the other. In the
former case, you are still thinking. In the latter case, you start applying
each of the strategies at the same time.
As you do so, some strategies turn out to be silly, others look
promising. You pursue the ones that are
promising. For example, you try ten different (random) variations on each of
the promising ones. Again, some will prove themselves just plain silly, but
others will look even more promising. And so forth. By trial and error (case
2.), you will always be working with a few promising strategies and possibly
with a few excellent ones. After a few days you may have found one or more strategies that cope perfectly well
with the situation. In case 1., you
will be without a strategy for as long as you are thinking. When you finally
find the best strategy (assuming that you have enough experience and
intelligence to find it at all), it may be too late. In many situations,
"design by trial and error" (case 2.) tends to be more efficient than
"design by a designer" (case 1.). So Darwin opted for "design without
a designer": nature builds species which are better and better adapted and
the strategy it employs is one of trial and error. The idea of evolution
established a new scientific paradigm that has probably been more influential
than even Newton's Mechanics or Einstein's Relativity. Basically, evolution takes
advantage of the uncertainty left in the transmission of genes from one
generation to another: the offspring is never an exact copy of the parents,
there is room for variation. The environment (e.g., natural selection)
indirectly selects which variations (and therefore which individuals)
survive. And the cycle resumes. After enough generations have elapsed, the
traits may have varied to the point that a new species has been created. Nobody
programs the changes in the genetic information. Changes occur all the time.
There may be algorithms to determine how change is fostered. But there is no
algorithm to determine which variation has to survive: the environment will
make the selection. Living organisms are so
complex that it seems highly improbable that natural selection alone could
produce them. But Darwin's theory of variation and
natural selection, spread over millions of years, yields a sequence of
infinitesimally graded steps of evolution that eventually produce complexity.
Each step embodies information about the environment and how to survive in it.
The genetic information of an organism is a massive database of wisdom accrued
over the millennia. It contains a detailed description of the ancient world and
a list of instructions for surviving in it. The gorgeous and majestic
logical systems of physical sciences are replaced by a completely different,
and rather primitive, system of randomness, of chance, of trial and error. Of course, one could object
that natural selection has (short-term) tactics, but no (long-term) strategy:
that is why natural selection has never produced a clock or even a wheel. Tactics, on the other hand, can achieve eyes
and brains. Humans can build clocks,
but not eyes. Nature can build eyes, but not clocks. Whatever humans build, it has to be built within a lifetime
through a carefully planned design. Nature builds its artifacts through
millions of years of short-term tactics. "Design" refers to two
different phenomena when applied to nature or humans. The difference is that
human design has a designer. Darwinism solved the problem
of "design without a designer": variation and selection alone can
shape the animal world as it is, although variation is undirected and there is
no selector for selection. Darwin's greatest intuition was that design (very complex design) can emerge
spontaneously via an algorithmic process. To be fair, Darwin already realized that natural
selection alone was not enough to explain the evolution of very complex traits
(such as the human brain itself). Thus he later introduced a second kind of
selection, that, while not as popular as natural selection, could actually
account for rapid development of complex organs in primates: sexual selection.
Sexual selection is due to the different way males and females of a species
behave towards reproduction: males compete for females, females choose males.
Thus males and females are under pressure to develop features that not only
will improve their chances of surviving in a hostile environment but will also
improve their chances of reproducing with a member of the other sex. Primates
are under the pressure of both natural selection and sexual selection
(competition for survival and competition for reproduction). Sex is not only
a footnote. Back to the beginning of the chapter "The Evolution of Life: Of Designers and Design" | Back to the index of all chapters |
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