Friday, February 1, 2013

What Is Life?















Two interesting articles on man-made chemical systems with strikingly lifelike characteristics. This relates more to the first few weeks, but it's still really cool. Check out the video on the first link. It's hard to believe those little guys aren't "alive."

It’s (Almost) Alive! Scientists Create a Near-Living Crystal

The ultimate goal of the work is to study how complicated collective behaviors arise from simple individual properties, perhaps informing molecular self-assembly projects, but it’s hard not to think about the origin-of-life implications.
“Here we show that with a simple, synthetic active system, we can reproduce some features of living systems,” Palacci said. “I do not think this makes our systems alive, but it stresses the fact that the limit between the two is somewhat arbitrary.”
Self-Replication Chemicals Evolve into Lifelike Ecosystem

Life makes more of itself. And now so can a set of custom-designed chemicals. Chemists have shown that a group of synthetic enzymes replicated, competed and evolved much like a natural ecosystem, but without life or cells.
"So long as you provide the building blocks and the starter seed, it goes forever," said Gerald Joyce, a chemist at the Scripps Research Institute and co-author of the paper published Thursday in Science. "It is immortalized molecular information."
Joyce’s chemicals are technically hacked RNA enzymes, much like the ones we have in our bodies, but they don’t behave anything like those in living creatures. But, these synthetic RNA replicators do provide a model for evolution — and shed light on one step in the development of early living systems from on a lifeless globe.

1 comment:

John Latto said...

That is very cool. It seems we have a very intuitive sense of what life is even if we can't define it.