“I thought to myself, ‘Oh my goodness — am I seeing what I think I’m seeing?’ All of a sudden I was jumping up and down. That was when I realized that this is what I had dreamt.”
Everything we thought we knew about early humankind may need to be tossed out like yesterday’s news. “All bets are now off,” researchers looking into humankind’s early ancestors are saying. Lucy is out and Anamensis is in.
Research published last month in the journal Nature pointed to the recent discovery of a nearly complete 3.8-million-year-old skull of an early, ape-like human ancestor in Ethiopia as evidence that not all is what it seems when it comes to decoding the genetic origins of modern humans.
The prevailing view that an ape-like hominid named Lucy was a member of the species that first gave rise to early humans may have to be reconsidered.
Prof. Yohannes Haile-Selassie, a palaeoanthropologist affiliated with the Cleveland (Ohio) Museum of Natural History, discovered the fossil at Miro Dora, an archeological site in Mille District, in Ethiopia’s fossil-rich Afar State. Prof. Haile-Selassie says the specimen is the most well-preserved specimen yet of the ape-like human ancestor named Australopithecus anamensis, the oldest known australopithecine whose kind may have — emphasis on the “may” — existed as long ago as 4.2 million years.
It’s now thought that anamensis is the director ancestor of a later, more advanced species called Australopithecus afarensis, the earliest human in the grouping known as Homo, which includes all humans alive today. “Lucy” was the first afarensis to be discovered, in 1974. Researchers nicknamed her Lucy after the Beatles song, Lucy in the Sky with Diamonds, which had been playing on a transistor radio at the excavation site at the time of the skeleton’s discovery. Lucy was hailed as “the first ape to have walked,” and captured the public imagination.
Researchers now believe anamensis and afarensis overlapped in time, because of the dates involved.
This is important because it means the former could not have evolved into the latter in neat, linear evolutionary terms, as researchers believed until recently.
They were separate species, living at much the same time, and may even have encountered one another, much as scientists have confirmed Neanderthals lived among early Homo sapiens, the direct ancestors of modern humans. It was once thought Neanderthals and sapiens were separated by thousands of years; now it appears they have rubbed elbows, as it were, and quarrelled over territory. Anamensis and afarensis co-existed for at least 100,000 years.
This matters because it means additional overlapping between advanced ape-like species probably happened, which in turn increases the probability that many different roots fed into modern humanity’s family tree, and not just the one-size-fits-all branch model.
Anthropologists have never cared for the term “missing link” to describe a fossil that is part-ape and part-human. These new findings suggest there is not one missing link, but rather dozens, even hundreds of links that are not missing so much as undiscovered. Yet.
Anamensis is only the latest in a recent string of discoveries that suggests there was no smooth, direct line of ascent in human evolution. The picture books may have to be redrawn completely.
Far from discouraging scientists, this excites them. It means there is so much more we can learn, and established research organizations can’t help but be galvanized and re-energized by the new findings. What we assumed to be true is no long that.
https://www.sciencemag.org/news/2019/08/stunning-ancient-skull-shakes-human-family-tree
https://www.nytimes.com/2019/04/10/science/hominins-human-evolution.html
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