Sixty years ago, when The Evening Sun's H. L. Mencken covered the trial of John Scopes, a young teacher charged with violating Tennessee law by teaching evolution in the public schools, the idea that people were descended from ape-like creatures seemed novel, shocking, even sacrilegious. Darwin's pathbreaking "Origin of the Species" had been attacked as blasphemous by fundamentalists like William Jennings Bryan, the prosecutor in the Scopes trial, who interpreted the biblical account of Creation in Genesis as literally God's truth.
Reports last week that scientists have found the bones of the oldest known ancestor of human beings no doubt will set Bryan spinning in his grave all over again. The remains, discovered in Ethiopia in 1992 by an international team coordinated by Timothy White of the University of California at Berkeley, appear to be some 4.4 million years old, more than a half-million years older than the earliest human ancestor previously unearthed.
The find provides a key link in the evolutionary chain connecting modern humans with the earliest primates, who first appear in the fossil record about 65 million years ago, near the end of the age of the dinosaurs. Researchers believe the line that led to modern humans split off from the ancient apes between 4 million and 6 million years ago.
Until now, the earliest human ancestor to turn up had been Australopithecus afarensis, which lived some 4 million years ago on the open plains of East Africa. The newly found remains, dubbed A. ramidis, belonged to a creature who lived in an area that appears to have been forested woodland. The discovery thus seems to support a theory that the earliest hominids, or human-like creatures, developed the ability to walk upright on two legs while they still lived in the forest, rather than after they had ventured out into the open.
Old as these bones are, they still do not represent the elusive "missing link" scientists have long sought as the common ancestor of both humans and apes. Biomolecular evidence suggests that creature, of whom no trace has yet been found, may have lived as much as a million years earlier than A. ramidis.
Of course, millions of years from now modern humans will also have joined the fossil record. If there are intelligent creatures around then to dig up our bones, you can be sure anyone who dares suggest we might be their ancient ancestors will be roundly denounced. Darwin was right -- but that probably won't make it any easier for our descendants eons hence to swallow the truth about their humble origins.