CLOSE
Original image
"Kotias remains," Eppie Jones

DNA From a Fourth Tribe of European Ancestors Has Been Found

Original image
"Kotias remains," Eppie Jones

Prior to summer 2015, researchers believed that all Europeans had a shared ancestry stemming from three tribal populations: European hunter-gatherers, early European farmers, and ancient North Eurasians. According to an article published this week in the journal Nature Communications, by studying the genomes of ancient skeletons found in two caves in Western Georgia (Kotias Klde and Satsurblia), geneticists have discovered a fourth group, Caucasus hunter-gatherers, who also contributed DNA to the continent.

Satsurblia cave, where another sample was found. Image credit: Eppie Jones

The Caucasus hunter-gatherers are believed to have mixed with another group of hunter-gatherers around 25,000 years ago, "laying the genetic foundations of the Yamnaya people," according to the BBC. Yamnaya herders from the region, which includes present-day Russia and the Ukraine, entered Europe around 5000 years ago, possibly because of the spread of disease back home.

"The question of where the Yamnaya come from has been something of a mystery up to now," Andrea Manica, of the University of Cambridge, told the BBC. "We can now answer that as we've found that their genetic make-up is a mix of Eastern European hunter-gatherers and a population from this pocket of Caucasus hunter-gatherers who weathered much of the last Ice Age in apparent isolation." The group may have been responsible for introducing Indo-Aryan languages to the region, and are also believed to have influenced the cultures of central and south Asia.

To read more about the analysis of the skeleton genomes and of the Caucasus, head over to Nature Communications.

arrow
science
6 Pioneering Facts About Mary Leakey

Fossil bones and the earliest footprints of our human ancestors are just a few of Mary Leakey’s groundbreaking discoveries. Get to know the legendary paleoanthropologist, and learn how her serendipitous finds forever altered scientists’ understanding of human origins.

1. MARY LEAKEY WAS A BORN EXPLORER.

Mary Leakey (1913-1996), née Mary Nicol, was destined to be an explorer: Her father, Erskine Nicol, was a landscape painter, and the family traveled extensively through France, Italy, and Switzerland. While staying in a commune in southern France, 12-year-old Mary became interested in archaeology after meeting Elie Peyrony, a French prehistorian excavating a cave. Mary dug through his tiny finds—which included fine points, scrapers, and flint blades—and sorted them into an amateur classification system.

2. FOSSIL HUNTING WAS IN HER BLOOD ...

Leakey’s parents were artists, but hunting for fossils was part of her heritage: Her maternal great-great-grandfather was John Frere, an 18th-century English government official and antiquarian who’s credited with first recognizing Stone Age flint objects as early weapons and tools.

3. ... BUT SHE WASN'T A GREAT STUDENT.

Leakey was intelligent, but she also had a rebellious streak. As a teen, she was expelled from several Roman Catholic convent schools—once for intentionally creating an explosion in a chemistry lab. Figuring she wasn’t cut out for a classroom, Leakey never finished high school, and decided to pursue independent studies in art, geology, and archaeology at the University of London instead. (“I had never passed a single school exam, and clearly never would,” the scientist later wrote in her 1986 autobiography Disclosing the Past.)

4. LEAKEY WAS AN ARTIST WHEN SHE MET HER FUTURE HUSBAND AND RESEARCH PARTNER, LOUIS LEAKEY.

Mary Leakey—who inherited her father’s artistic skills— ended up working as an illustrator for archaeological digs. An archaeologist introduced her to Cambridge University paleontologist Louis Leakey, who needed an illustrator for his book Adam’s Ancestors (1934). The two became lovers, but their union resulted in scandal, as Leakey was still married at the time. The couple married in 1936, after Leakey divorced his first wife.

5. MARY LEAKEY'S FIRST BIG DISCOVERY WAS PROCONSUL AFRICANUS.

Mary Leakey's first major discovery came in 1948 when she found a fossil skull fragment of Proconsul africanus, an ancestor of apes and humans, which later diverged into two separate species. The fossil was thought to be more than 18 million years old.

6. ANOTHER ONE OF MARY LEAKEY'S FAMOUS FINDS CAME COURTESY OF ELEPHANT POOP.

In 1978, Leakey was on an expedition in Laetoli, in Tanzania, when members of her camp engaged in a spirited elephant dung fight. A scientist fell down, and he noticed strange indentations on the ground that had been recently exposed by erosion. They turned out to be tracks made around 3.7 million years prior, from animals that had walked over damp volcanic ash. Examining these prints took several years, but the team's efforts paid off when Leakey noted that one of the prints seemed to be made by a hominin. This discovery showed that early humans began walking upright long before scientists thought they had.

Additional source: Ancestral Passions: The Leakey Family and the Quest for Humankind's Beginnings, Virginia Morell

Original image
Wikimedia Commons // Public Domain
arrow
Stones, Bones, and Wrecks
Researchers Unveil an Unusual New Theory For How Easter Island’s Statues Were Made
Original image
Wikimedia Commons // Public Domain

The Moai statues of Easter Island present one of the world's greatest technical mysteries. The stone heads (actually full bodies) that dot the island in the South Pacific are massive and number in the hundreds, prompting archaeologists to wonder how they got there in the first place. Now, as Newsweek reports, a group of researchers believe they're closer to finding an answer.

European sailors first arrived on Easter Island in 1722 and were greeted by a native population of 1500 to 3000. Along with the residents were 900-odd statues carved from solid rock, meaning there were fewer than four people for every massive monolith.

How was such a thin population able pull off such an impressive feat of architecture? According to researchers from Chile, New Zealand, and the U.S., it's possible they had help. Their new study published in the journal Frontiers in Ecology and Evolution suggests that the statues were carved and erected at a time when Easter Island supported a much larger population. Using data from the island, they estimated just how high the island's numbers may have reached.

Easter Island has the agriculture potential to sustain a maximum population of 17,500, researchers say. This estimate is based on the weather and soil quality of the island, 19 percent of which is capable of growing the sweet potatoes that fed inhabitants. "Despite its almost complete isolation, the inhabitants of Easter Island created a complicated social structure and these amazing works of art before a dramatic change occurred," lead author Cedric Puleston said in a statement.

If the Moai were constructed by a much larger group than the Europeans encountered, that would clear up some of the mystery surrounding the island. But it would also raise more questions. How, for instance, did the population fall so quickly in the few centuries between the statues' construction and first contact with Europeans? One theory is ecocide, which happens when an area is exhausted of its resources faster than it can replenish them.

The mystery of how the towering monoliths were transported across the island after they were built still remains. The indigenous people told Dutch explorers that the Moai walked themselves, an explanation an MIT professor put to the test when he designed a 2000-pound sculpture that could be shimmied long distances. But despite the numerous theories, hard evidence related to the figures' origins remains scarce.

[h/t Newsweek]

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios