We have said it before and we’ll say it again—at some point we will know the full story of human evolution.
Look at the discoveries that occurred between 2010 and 2020, based on a list compiled by the Smithsonian.
Ancient DNA confirmed a fossilized finger bone belonged to an undiscovered species of early humans called Denisovans. In fact, four new species were added to the human family tree in that 10-year span, including the mysterious Homo naledi.
In addition, the 3.8-million-year-old cranium of Australopithecus anamensis helped scientists see the face—not just fragments—of an early human species. This discovery challenged the previous assumption that A. anamensis was the direct ancestor of the species Australopithecus afarensis, including the famous “Lucy.” Thanks to the new cranium, we know the two species overlapped in time.
Also between 2010 and 2020, a research team found pieces of altered stone in Kenya that dated to 3.3 million years ago. These stones were larger and simpler than those that were previously thought to be the oldest stone tools. The discovery suggested that flaking stone tools arose at least 700,000 years before it became a regular habit in the lives of our ancestors.
And in 2017, a team of scientists re-excavated a cave in Morocco where a group of miners found skulls in 1961. Using CT scans, the scientists confirmed that the remains they found belonged to our species. In fact, the remains dated to about 300,000 years ago, which means that our species originated 100,000 years earlier than we thought. Whoa.
That’s pretty good work for a decade!
And now comes word that an ancient skull found recently in eastern China dates back to the late Middle Pleistocene. And that skull could signal a previously unknown type of hominin.
Repeat: a previously unknown type of hominin.
The skull’s lower jaw drew the attention of researchers, since it differed from every known taxonomic group. It had features of both modern humans and Pleistocene hominins.
The key? No significant chin, which makes it similar to the aforementioned Denisovans. Homo sapiens and Denisovans are distinct hominin groups that both evolved from Homo erectus.
“The skull does not fit the evolutionary path of any known hominin. The research team initially theorized that this could be because it belonged to a 12- or 13-year-old. But later comparisons with both mature and juvenile hominin skulls from the same era showed that this was not the case,” stated an article on ExplorersWeb.
Was this a hybrid between modern humans and Denisovans? The skull seems to fit that theory.
But the new skull also lines up with several hominin fossils from China, and from this same timeline, that were previously considered anomalies.
It’s possible this particular cranium could be the missing link in the evolution of humans. But, as always, “more research is needed before scientists can conclusively add a new branch to our family tree,” states the article.
One “missing link” at a time, the picture is coming together.