The LTEE has run for over 10,000 days and almost 67,000 generations. It’s time to shut it down, as of today.
It’s been a hell of a lot of work, and we have almost nothing to show for it. As some astute commentators have noted around the web, the creatures in the flasks are still just bacteria—creatures, just as they were created.
If you read the first LTEE paper*, you’ll see we predicted the bacteria should become yeast by about 5,000 generations, nematodes at 15,000 generations or so, and fruit flies by 30,000 generations, maybe 35,000 at the outside.
After that, we’d have to stop the experiment anyhow, because we wouldn’t be able to freeze and bring them back alive any longer.
Plus, we’d have to get IRB approval for human experimentation if we ran it much past 50,000 generations.
Well, we’ve given the LTEE all this time, and still … they ’re just bacteria. I guess we’ve proven that Charles Darwin was wrong after all.
As an astute reviewer pointed out when we submitted that first paper, “I feel like a professor giving a poor grade to a good student.” I should’ve listened and quit way back then. It would’ve saved everyone a lot of time and effort.
Now it’s going to be a hell of a lot of work next week emptying the freezers and autoclaving all those samples.
* Lenski, R. E., M. R. Rose, S. C. Simpson, and S. C. Tadler. 1991. Long-term experimental evolution in Escherichia coli. I. Adaptation and divergence during 2,000 generations. American Naturalist 138: 1315-1341.