No doubt others will weigh in on the significance, or lack of it, of the latest ballyhooed news from the world of human origins research: the dating of remains identified as archaic Homo sapiens to 300,000+ years ago, which is about 100,000 years older than the previously known oldest specimens.
The cache of fossils, meager as usual, were found in North Africa — Jebel Irhoud, Morocco – which was one surprise. From the story at Smithsonian Magazine:
Newly discovered fossil discoveries in Africa have pushed back the age we know modern humans roamed the Earth by roughly 100,000 years — and injected profound doubt into what we thought we knew about where humanity first arose.
“This material represents the very roots of our species — the oldest Homo sapiens ever found in Africa or elsewhere,” said Jean-Jacques Hublin, an anthropologist at the Max Planck Institute for Evolutionary Anthropology, in a press conference this week. Hublin was the lead researcher for one of the two studies published on the discoveries in yesterday’s issue of the journal Nature.
Up until now, the oldest definitive modern human fossils were known to be around 200,000 years old, and had been found in modern-day Ethiopia. These discoveries helped cement the dominant theory among anthropologists in recent decades that modern humans, Homo sapiens, evolved in East Africa and then migrated north into Asia and Europe. This region has therefore been dubbed the “cradle of humankind” (though South Africa also lays claim to the title).
“Our results challenge this picture in many ways,” Hublin said. The fossils his team studied come from a cave in central Morocco, thousands of miles away from East Africa. They suggests that, by 300,000 years ago, modern humans had already spread across Africa. Recall that the continent that was much easier to cross then, with lush grasslands and lakes residing where the forbidding Sahara Desert lies today.
In the mainstream science venues I don’t see any direct acknowledgment of the challenge that, given conventional assumptions about human ancestry, that means considerably less time, 100,000 years less, for unguided evolutionary processes to accomplish the transition to us. Pushing origins back in time – whether of our species, whales, or life itself – is rarely good news for evolution.
The hive mind of science journalism tends not to notice such things. Speaking of which, do you ever observe how many headlines on stories like this all seem to have been written by the same person?
- “Oldest Fossils of Homo Sapiens Found in Morocco, Altering History of Our Species” — New York Times
- “Earliest fossil evidence of Homo sapiens found in Morocco, rewriting the story of our species” – Los Angeles Times
- “A new fossil discovery in Morocco will rewrite the history of human evolution” – Quartz
- “New Fossil Discovery Rewrites History of First Human Beings” – Extreme Tech
- “The story of human evolution in Africa is undergoing a major rewrite” – Vox
- “Oldest Homo sapiens fossil claim rewrites our species’ history” – Nature
It would be an interesting study for another time to dig down and figure out who gave them this language about “rewriting” history to begin with, which, once given, is taken up and repeated by a range of publications.
The word choice, though, is ironic. In a normal editorial process, “rewriting” is done typically to bring enhanced clarity. But when it comes to human origins, the truth is much closer to what biologist Jonathan Wells reminded us of the other day.
The problem with such fossil finds is that they never provide the lasting clarity about human origins that scientists, and the public, crave. “Instead of ending up with a nice clean line from an apelike creature, a chimpanzee-like creature,” says Dr. Wells, a U.C. Berkeley-trained embryologist, “each discovery complicates matters even more than they were complicated before.”
The more that experts on human evolution know about our origins, the less they seem to actually understand. Given evolutionary presuppositions, the direction of research and learning is not from lesser to greater clarity, but just the opposite. The result is, as Scientific American more candidly puts it, a “mess” (“Ancient Fossils from Morocco Mess Up Modern Human Origins”). If that is the case, maybe the problem is with the presuppositions.
Photo: Jebel Irhoud, © Shannon McPherron, MPI EVA Leipzig (License: CC-BY-SA 2.0).