Will the question of human origins and evolution be rewritten? If you want to ask, among the many disciplines, which discipline’s knowledge will be turned upside down every five years? Well, paleoanthropology is definitely on the list. Due to the archaeological evidence that pale

Human origins and the question of evolution will be rewritten?

If you want to ask, among many subjects, which subject will have its knowledge changed every five years?

Then, paleoanthropology must be on the list. Due to the archaeological evidence that paleoanthropologists continue to obtain and the emergence of new research tools, paleoanthropology makes new major discoveries basically every year, and they are often subversive.

During this time, from Purdue University from the University of the Witwatersrand Dominic Stratford, and Laurent Brussels etc. The researchers jointly published a paper titled "Cosmogenic Nuclide Dating of Australopithecus Sterkfontein, South Africa" ​​in the "Proceedings of the National Academy of Sciences ". In this paper, researchers proposed a discovery that could rewrite the origins and evolution of humans.

So what is going on?

To understand this issue, we have to start with the original theory of human origins.

The Origin of Humanity

We all know that before humans, dinosaurs were the absolute overlords on the earth. From the perspective of biological taxonomy , dinosaurs and humans are completely different species under different "classes".

Dinosaurs dominated the earth for nearly 160 million years. Finally, 65 million years ago, they were mass-extinct due to an asteroid with a diameter of 10 kilometers hitting the earth. Only a small branch of them later evolved into modern times. birds.

One more thing, there is also a view that the reason why dinosaurs became extinct is because of global volcanic eruptions.

After the dinosaurs stepped off the stage of history, mammals on the earth began to rise. One of them is very representative. They are: Primates.

After tens of millions of years of evolution, the ancestors of humans and the common ancestor of humans and chimpanzees began to diverge about 8 million years ago. Among them, one branch is the common ancestor of humans and apes. This branch continues to branch out and slowly evolve. About 2.2 million years ago, the first species of the genus Homo, Homo habilis, was born. As for the birth of and , there are many opinions here.

It was previously a common belief that humans originated from the East African savannah. The people who evolved into the earliest humans were Australopithecus also from the East African savannah. Is there any evidence?

Actually, there is quite a lot of evidence. The most representative one is Lucy , known as the "grandmother of mankind". She is one of the most complete ancient human fossils excavated to date.

Lucy is a typical Australopithecus who lived about 3.2 million years ago. Research shows that although Lucy mainly moves in trees, she can actually walk upright and her speed is quite fast, basically reaching 1 meter/second.

I would like to add here that in paleoanthropology, the two key indicators for the current definition of "human" are: habitual upright walking and brain capacity greater than 650 ml. Lucy meets the first criterion. Although her brain capacity does not reach 650 ml, it still reaches 400 ml.

Therefore, there was a previous view that Homo habilis probably evolved from the Australopithecus in the East African savannah. Is that really the case?

Mrs. Price

Lucy is not the only Australopithecus fossil discovered. In fact, many Australopithecus fossils have been found in Africa. Among them, one fossil is also very representative. It was excavated in the Sterkfontein Cave northwest of Johannesburg, South Africa in 1947. It was later called: Mrs. Price.

In addition to Mrs. Price, many Australopithecus fossils were also found in Sterkfontein Cave. Previous research on Mrs. Price believed that it mainly existed for about 2.1 million to 2.6 million years .

This research discovery has triggered a great controversy in the academic world, because Homo habilis lived 2.2 million years ago. In other words, in theory, Mrs. Price should have interacted with Homo habilis, but in fact, in Sri Lanka No fossils of Homo habilis have ever been found in Tekfontein Cave.

Then there is a possibility: did make a mistake in dating Mrs. Price?

Because Mrs. Price’s fossil is too old, which makes it very fragile, there is no way to directly date it. Scientists could only rely on sediments near the excavation site to make calculations.

As a result, the latest research has found that the scientists happened to be measuring flowstone deposits that were younger than the rest of the Sterkfontein Cave. In other words, the measurement was really wrong.

So the question is, when did Mrs. Price live?

Scientists also excavated other Australopithecus fossils near Mrs. Price's excavation site, one of which is called Littlefoot. Scientists dated "Little Foot" and found that it lived 3.67 million years ago.

This discovery also led scientists to decide to re-date the sedimentary rocks around Mrs. Price. This time, a brand-new dating technology was used: cosmogenic nuclide dating technology .

This technology mainly determines the age of fossils by observing the levels of rare isotopes produced when rocks containing quartz are hit by high-speed particles from outer space.

As a result, scientists found that Mrs. Price lived between .7 million years ago and 3.4 million years ago, which is even older than Lucy. So what does this discovery mean?

Human origins come from co-evolution in Africa

Previously, it has been believed that the Australopithecus in South Africa are much "younger" compared to the Australopithecus in East Africa . At the same time, some are even "homo habilis" with the earliest species of Homo. "There is overlap. Therefore, scientists generally believe that humans evolved from the Australopithecus in East Africa.

This discovery directly pushed the Australopithecus in South Africa back one million years, which overturned the view of the "East African origin theory". This means that the evolutionary path from Australopithecus to humans is far more complicated than we imagined.

Since there were millions of years, it was no problem for ancient humans to travel within a range of 4,000 kilometers, integrate with each other, and reproduce with each other. Therefore, the origin of humans is the result of the co-evolution of Australopithecus from Africa, not just the Australopithecus on the East African savannah.

In other words, during that period, various apes throughout Africa may have been fully genetically communicating and evolving together. The evolutionary tree should be extremely complex. There have even been many species that we don't know about, and one of them evolved into modern humans.

According to this theory, the earliest ancestors of humans in the world should have lived in Africa, not East Africa. We Chinese are also Homo sapiens . According to modern mainstream theory, Homo sapiens originated in Africa, so our ancient ancestors also lived in Africa.

Later, with the increasing population and changes in the environment, humans began to leave Africa and spread to all parts of the world.

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