Athletic Frogs Have Faster-Changing Genomes

Juan C. Santos of the National Evolutionary Synthesis center Durham, North Carolina, has researched that physically fit frogs have faster changing genomes, but that the rate of change within the frogs DNA is vast throughout the different species.  A theory first proposed in the 1990’s stated that species that have a higher resting metabolic rate are the species whose DNA will change at a faster rate.  After this theory was researched it was not supported by the findings.  Santos discovered that the different species had to be studied during periods of physical activity and not during periods of rest, as was done during the first studies.  Santos examined more than 500 frogs of more than 50 species.  He did so by setting up a “hamster like wheel” that rotated as the frog ran around it.  He did so in four minute intervals, measuring the oxygen intake of each frog.  Santos concluded that the species that had a higher level of extracting oxygen were the more physically fit species.  In addition, Santos had found that the athletic frog species tended to have faster changing genomes.   He did so by setting up a “frog family tree” that used DNA from fifteen frog genes.  This was the only factor studied that completely corresponded to the pace of evolution.  Although Santos has discovered that physically fit frogs having faster changing genomes, the reason why they do is still known.