Meet the ancestor: 3.8 million-year-old skull found in Ethiopia
Scientists have announced the landmark discovery in Ethiopia of a nearly complete skull of an early human ancestor that lived 3.8m years ago - a species boasting an intriguing mixture of apelike and human-like characteristics.
The fossil, dubbed MRD, which provides insight into a pivotal period for the evolutionary lineage that eventually led to modern humans, belongs to the species Australopithecus anamensis which first appeared 4.2m years ago.
This species is considered the direct ancestor of Australopithecus afarensis, the species best known from the famous partial skeleton nicknamed Lucy.
She was unearthed in 1974 about 56km from the site in the Afar region of Ethiopia where the MRD skull was found in 2016. Lucy dates from about 3.2m years ago.
MRD and Lucy together stand as watershed fossils for illuminating early human ancestors.
"We are talking about the most complete cranium of an early human ancestor ever found in the fossil record older than 3m years," said Cleveland Museum of Natural History paleoanthropologist Yohannes Haile-Selassie, who made the find.
MRD's species, which was bipedal but may also have been able to move around in trees, was much smaller than modern humans. Its skull measures about 20cm front to back and is 11.5cm wide.
Previous research suggested the species reached about 5ft tall, but the researchers did not give a height estimate for what they believe is an adult male.
It hails from a time between 4.1m and 3.6m years ago, when early human ancestor fossils are exceptionally scarce.