Emergence of Digital Life

I saw this article on Slashdot today touting the "first digital simulation of an entire life form," and couldn't help but think of the Karl Sims' "evolved virtual creates" that we saw a few weeks ago during our discussion of evolutionary algorithms. Though the mechanisms and scale of simulation are wholly different (Sims, as I understand it, worked with locomotion mechanisms, while these researchers worked on the cellular level)--the resulting "life forms" existing only in virtual space are quite similar in concept. The premise of both experiments is also remarkably similar in that both groups believed that they could effectively simulate organic life forms using computer algorithms. What I found particularly interesting was the discussion that ensued on Slashdot: many of the posters touched on themes that have come up repeatedly in class. Several tackled the more philosophical "What is life?" question and asked whether or not a life form that exists solely in a virtual context can be "alive." Some argued for and others against, but a sizable contingent argued for the idea that "life is not a binary distinction"--that is, there is a continuum of "life" along which some things are more alive than others. I thought that this concept dovetailed quite nicely with some of our earlier class discussions. It was also interesting to see that Conway's Game of Life found its way into the discussion. Some of the comments along these lines were a bit tongue in cheek, but I do think they raise important questions: If we start from the premise that "digital life" can be created, how do we distinguish between things that are alive on the computer and things that are not alive? Is Conway's Game of Life more or less alive that Karl Sims' evolved creatures or these researchers' evolved virus? If we work from the idea that life forms have some sort of "purpose" or "will", does that mean that, say, a simulation of traffic jams is alive because it has a purpose and unfolds organically? Are CAs alive? Can artificial intelligence create a "living" device? As we start to see more and more of these "computer-based organisms", I think that the "What is life?" question will become even more vexing as the obvious distinctions become less clear.