The AAAS meeting came to a close today. At one of the last sessions, a panel discussion on "Major Transformations in Evolution: The State of the Art and Public Understanding," John Relethford, a biological anthropologist at the State University of New York College at Oneonta, listed the top 10 things every person should know—and remember—about the origin of humans:
1. Humans evolved.
Human evolution is a fact—and the fact that we are just another species does not detract from our "specialness defined on a spiritual level."
2. Humans did not evolve from modern apes.
Species evolve over time, sometimes without the disappearance of the parental species. We have to be careful not to confuse "apes" with "modern apes."
3. We study human origins (plural) and not a single human origin.
4. Human evolution was "feet first."
In a sense, our ancestors were bipedal apes. When they began walking upright, they still had an ape-size brain, apelike teeth, and no tool technology.
5. Brain size did not increase all at once or at the same rate.
6. "There ain't no such thing as a free lunch."
In other words, nothing in evolution is free. Any adaptation, whether it be the ability to walk upright, our larger brains, or our vocal anatomy, must be considered in terms of the balance of benefits and costs.
7. Our ancestors were not always alone.
Evolution is more like a bush than a tree. It appears that humanlike species lived at the same time and place as other bipedal cousins.
8. Expect the unexpected
New discoveries, like the "Hobbit" skull found in Flores in 2003, will lead to new interpretations and surprises. Some of our hypothesis will be confirmed, while others are rejected—that's part and parcel of the scientific process.
9. Our ancestors were not dummies.
The archaeological record shows that change is slow but steadily increasing, and the pace of cultural change has accelerated. We're not smarter than our ancestors; we've just accumulated more knowledge.
10. Humans of the near future—of 2525, say—will look pretty much the same.
But there's no telling what humans will be like behaviorally or culturally, or whether humans will be extinct.
—Heather Wax