origin of humans; Erectus in Ethiopian highlands (Origins)

by David Turell , Friday, October 13, 2023, 20:29 (198 days ago) @ David Turell

Two million years ago:

https://www.newscientist.com/article/2397291-early-humans-lived-in-ethiopian-highlands-...

"Ancient humans were living in the highlands of what is now Ethiopia as early as 2 million years ago. A reanalysis of a fossilised jawbone from the region confirms that it belonged to a Homo erectus, and represents the earliest evidence of hominins living in such high-altitude areas.

"The highlands represent “a third pole for human evolution in Africa”, says Margherita Mussi of the Italo-Spanish Archaeological Mission at Melka Kunture and Balchit, based in Rome. Hominins have been found in large numbers in eastern and southern Africa, but not to date in upland areas.

***

"Mussi and her team used synchrotron imaging to study Little Garba’s teeth, which hadn’t yet erupted from the jawbone. They compared the shape of the teeth to those of multiple hominin species. “The teeth are a very good marker, so we can say for sure this is indeed an early Homo erectus,” says Mussi.

"In a previous study published in 2021, Mussi’s team also re-dated the Garba IV site. It consists of layers of sediment laid down over time. In the sediments, the researchers found traces of past shifts in Earth’s magnetic field, which could be matched to similar records elsewhere. Based on this, they conclude that Little Garba is 2 million years old. This makes it one of the oldest H. erectus ever found.

***

"Furthermore, the researchers re-examined the stone tools found in the sediments at Garba IV. They say there is a transition from older and simpler Oldowan tools to more sophisticated Acheulean tools between 2 and 1.95 million years ago. The Acheulean tools were harder to make because they required careful planning, but they opened up a wider range of foods.

"Putting these lines of evidence together, Mussi argues that the H. erectus population had to adapt to conditions in the highlands, and developed new styles of stone tools to do so."

Comment: H. erectus is our direct ancestor. They spread all over the Eastern hemisphere and undoubtedly coexisted with early H. sapiens