THERE will be wailing in a certain Seattle think tank tonight! The Scripps Research Institute has issued this press release: Darwin in a Test Tube, subtitled “Scientists at Scripps Research Make Molecules that Evolve and Compete, Mimicking Behavior of Darwin’s Finches.” Here are some excerpts, with bold added by us:
A group of scientists at The Scripps Research Institute has set up the microscopic equivalent of the Galapagos Islands — an artificial ecosystem inside a test tube where molecules evolve to exploit distinct ecological niches, similar to the finches that Charles Darwin famously described in The Origin of the Species 150 years ago.
Let’s read on:
As described in an article published this week in an advance, online edition of the journal Proceedings of the National Academy of Sciences (PNAS), the work demonstrates some of the classic principles of evolution. For instance, research shows that when different species directly compete for the same finite resource, only the fittest will survive. The work also demonstrates how, when given a variety of resources, the different species will evolve to become increasingly specialized, each filling different niches within their common ecosystem.
But … but … we’re told those things have to happen by design! We continue:
Using molecules rather than living species offers a robust way to do this because it allows the forces of evolution to work over the course of mere days, with a trillion molecules in a test tube replicating every few minutes.
Ah, that gives the creationists an out. They used molecules. That’s not evolution! Here’s more:
For several years, Joyce [Scripps Research Professor Gerald Joyce, M.D., Ph.D.,] has been experimenting with a particular type of enzymatic RNA molecule that can continuously evolve in the test tube. The basis of this evolution comes from the fact that each time one of the molecules replicates, there is a chance it will mutate — typically about once per round of replication—so the population can acquire new traits over time.
Fascinating! We thought that stuff was only done with computer simulations. Moving along:
Two years ago, Voytek [Sarah Voytek, Ph.D., a recent graduate of the Scripps Research Kellogg School of Science and Technology] managed to develop a second, unrelated enzymatic RNA molecule that also can continuously evolve. This allowed her to set the two RNAs in evolutionary motion within the same pot, forcing them to compete for common resources, just like two species of finches on an island in the Galapagos.
In the new study, the key resource or “food” was a supply of molecules necessary for each RNA’s replication. The RNAs will only replicate if they have catalyzed attachment of themselves to these food molecules. So long as the RNAs have ample food, they will replicate, and as they replicate, they will mutate. Over time, as these mutations accumulate, new forms emerge — some fitter than others.
This is great stuff. One more excerpt, then you’ll have to click over to the Scripps Research Institute to read it all for yourself:
In the process, the molecules evolved different evolutionary approaches to achieving their ends. One became super efficient at gobbling up its food, doing so at a rate that was about a hundred times faster than the other. The other was slower at acquiring food, but produced about three times more progeny per generation. These are both examples of classic evolutionary strategies for survival, says Joyce.
Here’s a link to the published paper: Niche partitioning in the coevolution of 2 distinct RNA enzymes.
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