Deleterious alleles are, by definition, not beneficial and should be selected out. However, sometimes deleterious alleles are maintained in a population, despite their harmful effects. Scientists have proposed several explanations for this unintuitive quirk of biology. Overdominance, otherwise known as heterozygote advantage, and mutation-selection balance are two such explanations.
A recent article out of the Quarterly Review of BioPhysics, a peer reviewed journal out of the UK, made a startling and outrageous claim. According to the paper, the genetic code evolved, not always toward functionality, but towards thermodynamic stability, which just happened to coincide with functionality in many cases. The paper makes claims that are at odds with typical evolutionary explanations as well as some very interesting claims about thermodynamics applied to genetics. Lets have a look at this article and see what we can learn.
Today, perhaps the most well-known species that is falling off the extinction cliff is the cheetah. Scientists know that Cheetah viability is dropping, litter size is shrinking, and deformities are increasing. As Kelly (2001) pointed out, the effective population size in cheetahs is a mere fifteen percent of the actual population size, far below what is acceptable to maintain a species. The cheetah will go extinct and nothing can be done to prevent it.
There are small sections of the DNA scattered throughout the genome that repeat. Termed microsatellites, these repeats vary in length but are rarely more than a few nucleotides long. Evolutionists believe they have no function. However, given a created genome, that seems unlikely. Therefore we will take a brief look at microsatellites today to see whether there is evidence they have function.