One of the most problematic elements of having skeptics of evolution believe is the long time tables needed to account for the changes. Indeed, many skeptics simply cannot fathom the million year time tables needed for changes to occur as evidence.
However, there is now evidence that changes have occured that took place in about a year's time frame. The species was the Samoan island butterfly, commonly known as the Blue Moon or Great Eggfly butterfly, which had nearly disappeared by 2001. Researchers went back in 2005, and noted the same female/male ratio. However by the end of 2006, however, the number of males had recovered.
The culprit that was responsible for the near elimination of the male Hypolimnas bolina butterfly was a parasite called Wolbachia. This parasite was killing male butterfly embryos. But according to researchers, it appears that the butterflies evolved rapidly to develop more suppressor genes that helped protect the males against the parasites.
Within 10 generations that spanned less than a year, the proportion of males of the Hypolimnas bolina butterfly on the South Pacific island of Savaii jumped from a paltry 1 percent of the population to about 39 percent. This is evidence that parasites can be major drivers in evolution.
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