The Future of Evolution: What Will We Become?

livescience ^ | 16 November 2009 | Charles Q. Choi

[JoeProBono]

The past of human evolution is more and more coming to light as scientists uncover a trove of fossils and genetic knowledge. But where might the future of human evolution go? There are plenty of signs that humans are still evolving.

However, whether humans develop along the lines portrayed by hackneyed science fiction is doubtful.

Clichés dashed

An old cliché has the highly evolved humans of the future sporting large heads to hold their advanced enlarged brains, "but that's nonsense, whole nonsense," said paleontologist Peter Ward at the University of Washington at Seattle, author of "Future Evolution." "If you've ever gone through a childbirth or witnessed one," Ward says, "we're already anatomically right on the edge of how big our heads can go — our big brains have already caused extreme problems in childbirth, and if we had bigger and bigger brains, that'd cause more mothers to die in childbirth, so evolution would select against that......."

[gleeaikin]

You mention the survival of nearsighted people because of the invention of eyeglasses. Actually, nearsightedness may be caused by elongation of the eye socket because of lack of vitamin D. Thus the invention of clothes and the move north may be causing nearsightedness, and might never have become a problem if we retained our primitive state. (Lets Have Healthy Children, by Adelle Davis) I raised by sons according to her recommendations. My oldest is in his late 30s and has never had a cavity. My other son has had one cavity where a wisdom tooth grew in horizontal. The oldest is a hunk and is currently in Special Forces.

Regarding the large head and brain. Who is to say that women might carry their babies for a shorter time so that the head would be smaller at birth. Now that we have better living conditions, the mildly premature mostly live.

Then again we might have another Toba Volcano event (74 thousand years ago), such that most of the population is wiped out. Scientists now think that only 5 to 10,000 humans survived, which lead to a very limited gene pool. Also perhaps got rid of a lot of the more stupid and weaker humans.

[AnotherUnixGeek]

You mention the survival of nearsighted people because of the invention of eyeglasses. Actually, nearsightedness may be caused by elongation of the eye socket because of lack of vitamin D. Thus the invention of clothes and the move north may be causing nearsightedness, and might never have become a problem if we retained our primitive state.

Interesting. I wonder if any studies have been done regarding this - are people from areas which receive less sunlight more likely to be near-sighted? I did find a Wikipedia claim that up to 41% of adults in India and Malaysia, which both receive large amounts of sunlight, are myopic to some degree.

Personally, I'm California raised and became very near-sighted by the time I was in my teens (currently 20/20 with LASIK). My father was also near-sighted, as was his father. There is obviously a genetic factor. Without technology, none of us would ever have lived long enough to reproduce - some ancestor with the myopia trait would have died before reproducing as a result.