Question:

I was wondering what your thoughts would be on the article "Evolving yeast sheds light on life’s rise" singled-celled brewer’s yeast evolve into more complex, multi-celled organisms. This is a step towards showing us how life came about. This shows that lots of time is not needed for the origins of life. I read in your other article that’s atheists assume lots of time is needed. This is proof that we don’t need lots of time just the right conditions

Response:


I believe that this is a REALLY cool experiment. I am not sufficiently versed in this kind of experiment to comment very intelligently on whether or not it is a significant discovery or how unique this is. My intuition is that this discovery is not quite as unique as the ones announcing it are implying, but that is a bit speculative on my part.

Here is my response. What we are seeing in this experiment is probably not evolution. Whether it is important or not, I already said I am not sufficiently well acquainted with the experiment and with the discipline to say, but it is not evolution. By definition, evolution is change in genetic information over time caused by such natural processes as natural selection, sexual selection, mutation, independent assortment and other factors. I might be wrong, but I believe that the yeast being observed in these experiments are doing what they already have had the ability to do for an extremely long time. In other words, this particular species of yeast has had the ability to produce primitive colonies for a very long time. This ability is only expressed in particular environments, but it is not a new ability. If this property of brewer’s yeast evolved, it did so in the distant past. All that is happening in the experiment is that the tendency to form colonies of cells is expressed in the particular environment set up by the scientists in this experiment. 

I do not mean to downplay what they have observed, but their interpretation is questionable. What they ought to say, in my opinion, is that they have discovered a new thing that Baker’s yeast is able to do, not an example of evolution. I believe that we should wait until this experiment is published in the professional literature and the experts in the field respond. I predict that when they publish the significance will be put more in perspective.

There are more subtleties going on that my first take above. Apparently, they are subjecting yeast to mutation-prone environments. The implication is the tendency to form colonies is somehow increased by some sort of mutation which is caused. Let me make a couple of comments on this. First of all, the little media-friendly articles I saw did not mention the specific mutation-causing environment being used. Also, they do not mention what baker’s yeast do in a control experiment without the mutation-prone environment. In addition, it is possible that the changes may cause colony-formation, but that, in a real environment, the same change may make the yeast much less fit.
Again, I do not mean to imply that this experiment is not significant at all. However, I feel we should wait for the verdict of experts in

the field and should avoid over-hyping this experiment by calling what has been observed an example of "evolution."

John Oakes

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