Early humans left clues – footprints, chiseled rocks, genetic material, and more – that could reveal that our species survived and spread across the Earth. These old people were not that different from us; they traveled far and wide, joined together, and even sought natural resources (in this case, the reddish mineral ocher). Here are 10 things we learned about our human ancestors in 2020.
1. Mystery enthusiast
Early humans (homo sapiens) didn’t sleep with just one other. About 1 million years ago, H. sapiens had several trysts with a different mystery species, and our species still carries some of these genes today, a study in the journal PLOS Genetics found it.
It is possible that this mystery species was Standing man, but we may never know for sure because H. erectus extinct about 110,000 years ago, and scientists have no DNA of this species.
Read more: Mystery ancestor paired with ancient people. And his ‘nested’ DNA has just been found.
2. The oldest known human DNA is cannibal
The oldest known human DNA belongs Gay predecessor, a species that may have practiced cannibalism. And at 800,000 years old, it is a record breaker.
Scientists found the remains of six H. predecessor individuals in Spain in 1994, but it wasn’t until this year that a team of researchers extracted DNA from one of the teeth of these individuals, using the proteins in the enamel to create the segment of DNA she coded that. The team then compared and determined this DNA sequence with recent human dental samples H. predecessor is not a close relationship. Rather, it was probably a sister species of an ancestor that led to modern humans.
Read more: The world’s oldest human DNA found in an 800,000-year-old cannibal tooth
3. Early humans left stone “breadcrumbs” behind
When modern humans (homo sapiens) left the Horn of Africa about 130,000 years ago, they moved along the Arabian Peninsula. But which path have they taken? Now scientists have an idea, after finding sharp, human-made flint points in the Israeli Negev desert that, like “breadcrumbs”, mark an ancient route, according to ongoing research at the Israel Antiquities Authority.
Read more: Ancient stone ‘breadcrumbs’ reveal early human migration from Africa
So, where exactly did people walk in the Arabian Peninsula? Scientists know at least a few exact locations. Researchers have found 120,000-year-old human footprints among those of other ancient animals preserved in an ancient lake bed in Saudi Arabia’s Nefud Desert. These footprints are the earliest evidence of this homo sapiens in the Arabian Peninsula, the researchers said. During that time, the Arabian Peninsula was green and dotted with lakes, a welcoming place for migrant people.
Read more: Prehistoric desert footprints are the earliest evidence for humans in the Arabian Peninsula
5. The first Americans arrived 30,000 years ago
The first people to set foot in America may have arrived 30,000 years ago, two new studies show. That’s much earlier than researchers previously thought, with some scientists historically claiming that the first Americans showed up only 13,000 years ago.
In one study, published in the journal NatureThe excavation of a remote cave in northwestern Mexico uncovered man-made stone tools dating back to 31,500 years ago. In the other study, also published in Naturescientists took published data on early human activity in Beringia (the area that connected Russia to America during the last Ice Age) and performed an equation that modeled human distribution. The model showed that early humans likely arrived in North America at least 26,000 years ago.
However, the Americas were sparsely populated so long ago. There wasn’t a population explosion until 14,700 years ago, when the last Ice Age began to end, the latest study found.
Read more: The first Americans arrived on the continent perhaps 30,000 years ago
6. Ancient diversity
Just like today, thousands of years ago, America was a diverse place. An analysis of four ancient skulls found in underwater caves in the Mexican state of Quintana Roo shows that these individuals looked nothing alike: one skull resembled Arctic humans, another has European features, a third resembles early South American humans and the latter does not look like a population.
The skulls date back to between 13,000 and 9,000 years ago, just when the last Ice Age ended, according to the study, published in the journal PLOS One.
Read more: Skulls of ancient North Americans indicate multiple waves of migration
7. Advanced miners
Those same Mexican caves, now under water, hid another secret, scientists discovered in 2020. For years, divers have found the skeletons of ancient people, including the skulls mentioned above. This begged the question, What did ancient people do there in the first place?
Now new evidence suggests that some of these ancient people were miners. About 12,000 to 10,000 years ago, ancient people mined the caves for the red mineral ocher and left traces of their work, including the charred remains of fires, stone tools and stone markers, so they wouldn’t get lost in the pitch-black maze. Ocher was used for rituals and everyday activities, possibly also as an insect repellent or sunscreen.
Read more: Ice age mining camp ‘frozen in time’ found in Mexican underwater cave
8. Toddlers have always been squiggly
More than 10,000 years ago, a woman with a toddler on her hip put the child down, corrected it, and picked it up again as she continued her journey through the playa of what is now New Mexico.
Researchers found this woman’s footprints and those of the squirming toddler in White Sands National Park. With a length of 1.5 kilometers, this track is the longest late Pleistocene era double human trackway registered.
Read more: 10,000-year-old footprints show the journey of squirming toddler and caregiver
9. ‘Ghost’ population found in the genes of Stone Age children
Four children who died young between 8,000 and 3,000 years ago in what is now Cameroon had secrets in their DNA. After analyzing the DNA from the remains of these ancient children, scientists were surprised to find that a previously unknown “ghost” population of humans had contributed to the genomes of these children.
About one-third of the children’s DNA came from ancestors closely related to known hunter-gatherers in western Central Africa, the researchers found. But the other two-thirds came from an ancient source in West Africa, including a “long-lost ghost population of modern humans” about which nothing was known so far, the scientists reported in the study, published in the journal. Nature.
10. Polynesians and Native Americans joined
Today, dating apps can help people find partners. But 800 years ago, the Polynesians and the indigenous people of Colombia didn’t have apps – they had boats, and apparently one of these groups flew to the other and joined.
When researchers looked at Polynesian DNA, they realized that some carried a genetic signature similar to that of indigenous Colombians. But it’s unclear whether the Polynesians traveled to Colombia and then returned to Polynesia (with their Colombian-Polynesian children), or whether Colombians traveled to Polynesia, the researchers said.
“We can’t say for sure who contacted whom,” lead researcher Alexander Ioannidis, a postdoctoral researcher of biomedical data sciences at Stanford University, told Live Science.
Read more: Polynesians and Indians got together 800 years ago, DNA reveals
Originally published on Live Science.