Gapay, A. (2008). Faster cheetahs are better?

1. Darwin's natural selection is a theory of evolution in which everything is believed to change because of what nature selects to survive. This theory has limitations, though: it cannot produce a perfectly engineered trait. That evolution is constrained is quite obvious especially for big creature, even more especially with big specialized animas like the cheetah.

2. Lacking necessary genetic variation is one of the limitations of evolution. In this case, one can only operate with whatever genes are available. Darwin's selection theory is constrained because of species' histories. Here, basic body forms of species cannot be altered much. Trade-offs are limited because changing one feature for a better one can have worse results.

3. Cheetahs are the fastest animals on land. They can run up to 120 kph on short stretches. What may be done to make them run faster?

Cheetahs could run faster if they had "faster" alleles, but they would have to evolve many other features in their body. Different arrangements of leg muscles and bones would also be needed to cause cheetahs to run faster, or they would need to acquire genes to improve oxygen use. This, in turn would require metabolic mutations having to do with digestion and many other processes. It is not likely that a cheetah's evolution could accomplish a wide range of such changes; at least if it is to remain as a kind of cat.

4. Since we could breed animals to produce better strains, as we have done with dogs, we could also cut genes and past it to others in a process called genetic recombination.

A genetic experiment, however, is likely to have unpredictable effects, too. Thus, even if the cutting and pasting or breeding worked to produce a faster cheetah, that cheetah might not be the best overall: running faster has its disadvantages (overheating, for example). Producing a better cheetah will be a process so long and unpredictable, that even with the best forms of assistance man will not be patient or wise enough to handle all the mistakes that will have to be made.

In short, natural selection by the wild is probably the best way to produce a good cheetah--not perfect, but better than we can, at least for living in the wild, where cheetahs are at their most awesome beauty.

5. Each species evolved to be almost at its best that if we will change them into something we think is better, we will likely end up with something worse, or only limitedly better. Therefore, we should just be contented on how we were made, because this body of ours was made with our best on the creator's mind, and evolved accordingly.

But the really interesting thing about all this is an implication: If evolution cannot engineer a perfect trait, then at least some of the characteristics we have are not perfect; some even have no use. For instance, what use are dimples, or earlobes connected fully to the face, ar the ability to roll the tongue? Why are these "useless" traits there?

The answer strikes at the heart of strict Darwinism: survival of the fittest is not everything. One can also have survival of the lucky (genetic drift ad bottleneck phenomena), survival of the neutral (traits that are neither advantageous or disadvantageous), and in many cases, survival of the bad (e.g., sickle cell anemia) because the bad trait allows organisms to escape an even worse fate.

References:
http://evolution.berkeley.edu/evolibrary/article/0_0/misconcep_03
http://en.wikipedia.org/wiki/Cheetahs

(Gwen Alexis Gapas is a student at the University of Asia and the Pacific. lexi.gapay@yahoo.com)