Fossils Suggest Hominids Had Larger Range Than Previously Thought

Australopithecus afarensis fossils found near Nairobi show that the range of ancient hominids extends to the east of the Great Rift Valley.

AsianScientist (Mar. 31, 2016) – An international team of paleontologists led by Professor Masato Nakatsukasa of Kyoto University has found new fossils from Kenya which suggest that an early hominid species—Australopithecus afarensis—lived far eastward beyond the Great Rift Valley, much farther than previously thought.

The fossilized teeth and forearm bone from an adult male and two infant A. afarensis were found by the Kantis River in Ongata-Rongai, a settlement in the outskirts of Nairobi.

“So far, all other A. afarensis fossils had been identified from the center of the Rift Valley,” explains Nakatsukasa. “A previous Australopithecus bahrelghazali discovery in Chad confirmed that our hominid ancestor’s distribution covered central Africa, but this was the first time an Australopithecus fossil has been found east of the Rift Valley.”

“This has important implications for what we understand about our ancestor’s distribution range, namely that Australopithecus could have covered a much greater area by this age.”

A. afarensis is believed to have lived 3,700,000-3,000,000 years ago, as characterized by fossils like “Lucy” from Ethiopia.

Stable isotope analysis revealed that the Kantis region was humid, but had a plain-like environment with fewer trees compared to other sites in the Great Rift Valley where A. afaransis fossils had previously appeared.

“The hominid must have discovered suitable habitats in the Kenyan highlands. It seems that A. afaransis was good at adapting to varying environments,” notes Nakatsukasa.

The team’s survey also turned up masses of mammal fossils, including a few that probably belong to new species of bovids or baboons.

The authors write that the Kantis site was first noted in a 1991 geological survey. At that time, a farmer said that he and his family had come across fossilized bones from Kantis in the 1970s, although they did not recognize their importance.

Following airing of Kenyan television programs on paleontological research, locals gradually started to appreciate the fossils. Since then, Kantis and other sites have been identified thanks to fossil notifications from the local population.

The team welcomes this achievement not only for its academic implications, but also for the benefits to the local community.

“Kantis is in the vicinity of Nairobi, a major city,” said Nakatsukasa. “We hope that the discovery of the new site and the fossils will aid in increasing tourism, and in improving educational awareness of the local community.”



The article can be found at: Mbua et al. (2016) Kantis: A new Australopithecus site on the shoulders of the Rift Valley near Nairobi, Kenya.

———

Source: Kyoto University.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.

Asian Scientist Magazine is an award-winning science and technology magazine that highlights R&D news stories from Asia to a global audience. The magazine is published by Singapore-headquartered Wildtype Media Group.

Related Stories from Asian Scientist