Scientists are fond of running the evolutionary clock backward, using DNA analysis and the fossil record to figure out when our ancestors stood erect and split off from the rest of the primate evolutionary tree.
But the clock is running forward as well. So where are humans headed?
Evolutionary biologist Richard Dawkins says it's the question he's most often asked, and "a question that any prudent evolutionist will evade." But the question is being raised even more frequently as researchers study our past and contemplate our future.
Paleontologists say that anatomically modern humans may have at one time shared the Earth with as many as three other closely related types — Neanderthals, Homo erectus and the dwarf hominids whose remains were discovered last year in Indonesia.
Does evolutionary theory allow for circumstances in which "spin-off" human species could develop again?
Some think the rapid rise of genetic modification could be just such a circumstance. Others believe we could blend ourselves with machines in unprecedented ways — turning natural-born humans into an endangered species.
Present-day fact, not science fiction
Such ideas may sound like little more than science-fiction plot lines. But trend-watchers point out that we're already wrestling with real-world aspects of future human development, ranging from stem-cell research to the implantation of biocompatible computer chips. The debates are likely to become increasingly divisive once all the scientific implications sink in.
No comments:
Post a Comment