One of my cousins was in a class and the instructor stated that in 300 hundred years there will be no more natural blondes left in the world. Now, I know blonde hair is a recessive trait, but is this really possible?
It’s probably not impossible if there is enough mixing of the gene pool but I’d say the premise is flawed. Following that logic there should be no recessive genes in a population after a certain time.
Nonsense. Recessive, or, for that matter, dominant, genes don’t disappear from a population unless there’s a selective pressure against them, and even then, it’s tough. So unless there’s a sudden push to stop breeding with blondes, it ain’t going to happen.
In fact, isn’t it easier (i.e. deterministically possible) to breed dominant genes out of the gene pool? A directed breeding program would be able to eliminate to a high degree of confidence the existence of recessive genes, but I don’t think it would be possible to entirely eliminate it. Dominant genes, on the other hand, can be eliminated easily: Just don’t let those that express them breed.
I recently read an article that claimed the same thing, only it was saying 100 years, not 300. I didn’t give it much thought, but after reading the posts, I agree, it is unlikely.
That was found to be a hoax.
Depending on your definition of “natural,” advances in genetic engineering will probably see quite the opposite, providing a surfeit of blonde, blue eyed, large-chested women. Thanks to advances in pharmacology, they will have ravenous sexual appetites a no social pressure to discourage such expression.
P.S. By age 20, few “natural” blondes are blonde any longer.
“unless there’s a sudden push to stop breeding with blondes”
That definately ain’t gonna happen.
The recent news story was a hoax, but there really are some people who believe blond hair is likely to disappear. http://www.fortwayne.com/mld/newssentinel/4387406.htm
I seem to remember from my bio classes of years ago that there’s a rule of genetics that says that, unless there’s a change in selective pressure or beneficial mutations, the percentage of a population that expresses a given genetic trait will remain constant over time, regardless of whether it’s dominant or recessive. (It has something to do with logarhithms.) The rule was named after the two guys who figured it out.
Of course, maybe the decreasing isolation between geographically disparate populations (and the concommitant lessening of social barriers to miscegnation) count as a change in selective pressure.
–Cliffy
Right. The Hardy-Weinberg Law states that allele frequency in a population will remain constant, excluding the effects of selection and random mutations.