Natural Selection May Not Produce The Best Organisms

21 July 2008

 A team of researchers at The University of Texas has discovered that mutations, the driving force of evolution, that are helpful in the short run may be a hindrance in the long run. This project used the Vienna RNA folding software (designed by man) with the default parameters (designed by man) to calculate the way RNA folds (designed by... no one according to them) in order to see how RNA folding effects evolution.

 To fold an RNA would be like taking a mile long piece of Velcro, and rapidly folding it up in such a way to leave tails, hoops, loops, and attached runs in the precise order necessary for the cell to function correctly and at the same time using as little energy as possible. The kicker is, if you have a slightly longer tail or bigger loop, recombining the same RNA in a slightly different way can completely change its function. It does all of this without crossing over itself and tangling up into a knot.

 If RNA decides to change the way it folds, you will have a mutation. This mutation is usually harmful; however, it may be beneficial according to researchers. The problem this report points out is that Natural Selection only works on the beneficial mutations that exist right now. It does not know that a future mutation will produce an even better organism.

If Natural Selection happens: The best right now survives.
If Evolution happens: The best in the future survives.

Example:
What is better, light sensitive cells or an eye?

 Obviously the eye; however, light sensitive cells must have come first because they are simpler. At some point a creature would have had to preserve hundreds of useless mutations (eye lids, tear ducts, iris, muscles, veins, nerves, etc.) to develop an eye for the final product to work as a whole. How would a creature with only eye pieces survived Natural Selection better than a creature with light sensitive cells until all the pieces were working together?

1. How would the first RNA have known how to fold in the first place when we can not even figure it out using the best computers available?
2. How did the useless mutations would bypass natural selection to reach the final product over millions of years?
3. As the researchers point out, we have not even seen any long term beneficial mutations.

http://www.sciencedaily.com/releases/2008/07/080717201837.htm
http://dx.doi.org/10.1371/journal.pcbi.1000110