5.29.2009

Demonstrating Evolution With Robots?

I'm finding it hard to see how this is a demonstration of evolution:

Robots with fins, tails demonstrate evolution
POUGHKEEPSIE, N.Y. (AP) — Robots wag their tail fins and bob along like bathtub toys in a pool at a Vassar College lab. Their actions are dictated by microprocessors housed in round plastic containers, the sort you'd store soup in.

It hardly looks like it, but the two swimming robots were set loose in the little pool to study evolution, acting out predator-prey encounters from roughly 540 million years ago.

The prey robot, dubbed Preyro, can simulate evolution.

This is not like robot evolution in the "Terminator" movie sense of machines turning on their human masters. Instead, Vassar biology and cognitive science professor John Long and his students can make changes to the tail of Preyro to see which designs help it avoid the predator robot.

"We're applying selection," Long explains, "just like natural selection."

It's selection all right, just not natural selection. These roboticists are tweaking their design towards meeting a predetermined fitness criteria. They're assuming what nature would select for without really knowing. If their robot swims faster, does that indicate their hypothesis is correct and that they know what nature's criteria was? No. Evolution is random mutations with unguided natural selection. This isn't the same thing. It's interesting nonetheless, but this work does not "demonstrate evolution".

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