The future of evolution

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The Evolution of Man.
CBS News

(CBS News) In ways large and small, we humans are still evolving -- which led us to wonder what the future holds for our descendants generations from now. Dr. Jon LaPook has been looking into that:


As a species, human beings have evolved, and continue to do so. Just think how different we are from a half-million years ago.

Rob DeSalle, a curator at the American Museum of Natural History in New York, says modern man is much different from homo neanderthalensis, the Neanderthal.

"You're not squat like he is; you're not as robust in the ribcage as he is," he told LaPook.

These changes are the result of a process called natural selection - the key force in evolution. It's the way our genes increase the odds of survival of the species -- passing on desirable traits from parent to child. It helps explain how humans gained the upper hand over the Neanderthals that came before us.

Socialization and communication became more important than brute force, giving humans the advantage.

When asked who might win an arm-wrestling match -- a homo sapien or a Neanderthal -- Yale University evolutionary biologist Stephen Stearns replied, "Oh, I think the Neanderthal would probably take you down.

"But I think that as soon as the humans in the area found out about that, they would get together, and three or four of them would gang up on the Neanderthal."

Are we still evolving? DeSalle says our genes are going to change in coming years. It's the evolution of genes -- shaped by the world around us -- that will sculpt the human being of tomorrow."

Take, for example, the ease of global travel. It's already broken barriers when it comes to selecting a mate. DeSalle says, over time, that means racial differences will lessen.

He told LaPook, "Your descendants are probably going to have darker skin, darker eyes. There probably will still be a lot of variation in our facial features."

But blondes and redheads might become endangered species.

Signs of evolution are also evident in the human jaw; our jaws are much smaller, now that we no longer need to chew through tough nuts and roots.

And then there's our hair. Millions of years ago, long before our forebears wore clothing, hair was essential insulation. Someday, we're likely to have less of it -- especially if sexual selection dictates that hairless men and women are more attractive.

Could there be a little shift towards us being a little wimpier? "I would imagine that that shift probably happened over the last 5,000 to 10,000 years," answered DeSalle.

Stearns says as our world continues to evolve, we morph along with it.

"Culture changes so quickly," he said. "If you were to go back to, say, 1920, and ask anybody, 'Are you going to predict computers? Are you going predict iPads?' Nobody would have any idea of that."

Progress that is both a blessing and a curse. "I think that Google might actually be impairing our memory, because we just delegate so much to it that we used to have to remember," said Stearns.