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As a tool, evolution is good for three things: -
How to get somewhere you want but can't find the route to.
- How to get to somewhere you can't imagine.
- How to open up entirely new places to get to.
The third use is the door to an open universe. It is unsupervised,
undirected evolution. It is Holland's ever-expanding perpetual novelty
machine, the thing that creates itself.
Amateur gods such as Ray, Sims, and Dawkins have all expressed their
astonishment at the way evolution seems to amplify the fixed space they
thought they had launched. "It's a lot bigger than I thought" is the
common refrain. I had a similar overwhelming impression when I stepped
and jumped (literally) through the picture space of Karl Sims's
evolutionary exhibit. Each new picture I found (or it found for me) was
gloriously colored, unexpectedly complex, and stunningly different from
anything I had ever seen before. Each new image seemed to enlarge the
universe of possible pictures. I realized that my idea of a picture had
previously been defined by pictures made by humans, or perhaps by
biological nature. But in Sims's world an equally vast number of
breathtaking vistas that were neither human-made nor biologically
made -- but equally rich -- were waiting to be unwrapped.
Evolution was expanding my notions of possibilities. Life's biological
system is very much like this. Bits of DNA are functional units -- logical
evolvers that expand the space of possibilities. DNA directly parallels
the operation of Sims's and Koza's logical units. (Or should we say
their logical units parallel DNA?) A handful of units can be mixed and
matched to code for any one of an astronomical number of possible
proteins. The proteins produced by this small functional alphabet serve
as tissue, disease, medicines, flavors, signals, and the bulk
infrastructure of life.
Biological evolution is the open-ended evolution of DNA units breeding
new DNA units in a library that is ever-expanding and without known
boundaries.
Gerald Joyce, the molecular breeder, says he is happily into "evolving
molecules for fun and profit." But his real dream is to hatch an
alternative open-ended evolution scheme. He told me, "My interest is to
see if we can set in motion, under our own control, the process of
self-organization." The test case Joyce and colleagues are working on is
to try to get a simple ribozyme to evolve the ability to replicate
itself -- that very crucial step that Tom Ray skipped over. "The explicit
goal is to set an evolving system in motion. We want molecules to learn
how to make copies of themselves by themselves. Then it would be
autonomous evolution instead of directed evolution."
Right now autonomous and self-sustained evolution is a mere dream for
biochemists. No one has yet coerced an evolutionary system to take an
"evolutionary step," one that develops a chemical process that
heretofore didn't exist. To date, biochemists have only evolved new
molecules which resolve problems they already knew how to solve. "True
evolution is about going somewhere novel, not just reeling in
interesting variants," says Joyce.
A working, autonomous, evolving, molecular system would be an incredibly
powerful tool. It would be an open-ended system that could create all
possible biologies. "It would be biology's triumph!" Joyce exclaims,
equivalent, he believes, to the impact of "finding another life form in
the universe that was happy to share samples with us."
But Joyce is a scientist and does not want to let his enthusiasm run
over the edge: "We're not saying we are going to make life and it's
going to develop its own civilization. That's goofy. We're saying we
are going to make an artificial life form that is going to do slightly
different chemistry than it does now. That's not goofy. That's
realistic."
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