Space & Innovation

Why Did Ancient Europeans Disappear 14,500 Years Ago?

Genetic analysis shows some of Europe's earliest inhabitants mysteriously vanished toward the end of the last ice age and were largely replaced by others.

Some of Europe's earliest inhabitants mysteriously vanished toward the end of the last ice age and were largely replaced by others, a new genetic analysis finds.

The finds come from an analysis of dozens of ancient fossil remains collected across Europe.

The genetic turnover was likely the result of a rapidly changing climate, which the earlier inhabitants of Europe couldn't adapt to quickly enough, said the study's co-author, Cosimo Posth, an archaeogenetics doctoral candidate at the University of Tübingen in Germany. [Top 10 Mysteries of the First Humans]

Photos: Faces of Our Ancestors

The temperature change around that time was "enormous compared to the climactic changes that are happening in our century," Posth told Live Science. "You have to imagine that also the environment changed pretty drastically."

A twisted family tree Europe has a long and tangled genetic legacy. Genetic studies have revealed that the first modern humans who poured out of Africa, somewhere between 40,000 and 70,000 years ago, soon got busy mating with local Neanderthals. At the beginning of the agricultural revolution, between 10,000 and 12,000 years ago, farmers from the Middle East swept across Europe, gradually replacing the native hunter-gatherers. Around 5,000 years ago, nomadic horsemen called the Yamnaya emerged from the steppes of Ukraine and intermingled with the native population. In addition, another lost group of ancient Europeans mysteriously vanished about 4,500 years ago, a 2013 study in the journal Nature Communications found.

But relatively little was known about human occupation of Europe between the first out-of-Africa event and the end of the last ice age, around 11,000 years ago. During some of that time, the vast Weichselian Ice Sheet covered much of northern Europe, while glaciers in the Pyrenees and the Alps blocked east-west passage across the continent.

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Lost lineages To get a better picture of Europe's genetic legacy during this cold snap, Posth and his colleagues analyzed mitochondrial DNA - genetic material passed on from mother to daughter - from the remains of 55 different human fossils between 35,000 and 7,000 years old, coming from across the continent, from Spain to Russia. Based on mutations, or changes in this mitochondrial DNA, geneticists have identified large genetic populations, or super-haplogroups, that share distant common ancestors.

"Basically all modern humans outside of Africa, from Europe to the tip of South America, they belong to these two super-haplogroups that are M or N," Posth said. Nowadays, everyone of European descent has the N mitochondrial haplotype, while the M subtype is common throughout Asia and Australasia.

The team found that in ancient people, the M haplogroup predominated until about 14,500 years ago, when it mysteriously and suddenly vanished. The M haplotype carried by the ancient Europeans, which no longer exists in Europe today, shared a common ancestor with modern-day M-haplotype carriers around 50,000 years ago.

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The genetic analysis also revealed that Europeans, Asians and Australasians may descend from a group of humans who emerged from Africa and rapidly dispersed throughout the continent no earlier than 55,000 years ago, the researchers reported Feb. 4 in the journal Current Biology.

Time of upheaval The team suspects this upheaval may have been caused by wild climate swings.

At the peak of the ice age, around 19,000 to 22,000 years ago, people hunkered down in climactic "refugia," or ice-free regions of Europe, such as modern-day Spain, the Balkans and southern Italy, Posth said. While holdouts survived in a few places farther north, their populations shrank dramatically.

Then around 14,500 years ago, the temperature spiked significantly, the tundra gave way to forest and many iconic beasts, such as woolly mammoths and saber-toothed tigers, disappeared from Eurasia, he said.

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For whatever reason, the already small populations belonging to the M haplogroup were not able to survive these changes in their habitat, and a new population, carrying the N subtype, replaced the M-group ice-age holdout, the researchers speculate.

Exactly where these replacements came from is still a mystery. But one possibility is that the newer generation of Europeans hailed from southern European refugia that were connected to the rest of Europe once the ice receded, Posth speculated. Emigrants from southern Europe would also have been better adapted to the warming conditions in central Europe, he added.

Original article on Live Science.

In Images: An Ancient European Hunter Gatherer 8 Grisly Archaeological Discoveries In Photos: Human Skeleton Sheds Light on First Americans Copyright 2016 LiveScience, a Purch company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

This is a skull of a man who lived between 36,200 and 38,700 years ago in Kostenki in western Russia.

Back in the Beginning

To put a human face on our ancestors, scientists from the Senckenberg Research Institute used sophisticated methods to form 27 model heads based on tiny bone fragments, teeth and skulls collected from across the globe. The heads are on display for the first time together at the Senckenberg Natural History Museum in Frankfurt, Germany. This model is Sahelanthropus tchadensis, also nicknamed "Toumai," who lived 6.8 million years ago. Parts of its jaw bone and teeth were found nine years ago in the Djurab desert in Chad. It's one of the oldest hominid specimens ever found.

Australopithecus afarensis

With each new discovery, paleoanthropologists have to rewrite the origins of man's ancestors, adding on new branches and tracking when species split. This model was fashioned from pieces of a skull and jaw found among the remains of 17 pre-humans (nine adults, three adolescents and five children) which were discovered in the Afar Region of Ethiopia in 1975. The ape-man species, Australopithecus afarensis, is believed to have lived 3.2 million years ago. Several more bones from this species have been found in Ethiopia, including the famed "Lucy," a nearly complete A. afarensis skeleton found in Hadar.

Australopithecus africanus

Meet "Mrs. Ples," the popular nickname for the most complete skull of an Australopithecus africanus, unearthed in Sterkfontein, South Africa in 1947. It is believed she lived 2.5 million years ago (although the sex of the fossil is not entirely certain). Crystals found on her skull suggest that she died after falling into a chalk pit, which was later filled with sediment. A. africanus has long puzzled scientists because of its massive jaws and teeth, but they now believe the species' skull design was optimal for cracking nuts and seeds.

Paranthropus aethiopicus

The skull of this male adult was found on the western shore of Lake Turkana in Kenya in 1985. The shape of the mouth indicates that he had a strong bite and could chew plants. He is believed to have lived in 2.5 million years ago and is classified as Paranthropus aethiopicus. Much is still unknown about this species because so few reamins of P. aethiopicus have been found.

Paranthropus boisei

Researchers shaped this skull of "Zinj," found in 1959. The adult male lived 1.8 million years ago in the Olduvai Gorge of Tanzania. His scientific name is Paranthropus boisei, though he was originally called Zinjanthropus boisei -- hence the nickname. First discovered by anthropologist Mary Leakey, the well-preserved cranium has a small brain cavity. He would have eaten seeds, plants and roots which he probably dug with sticks or bones.

Homo rudolfensis

This model of a sub-human species -- Homo rudolfensis -- was made from bone fragments found in Koobi Fora, Kenya, in 1972. The adult male is believed to have lived about 1.8 million years ago. He used stone tools and ate meat and plants. H. Rudolfensis' distinctive features include a flatter, broader face and broader postcanine teeth, with more complex crowns and roots. He is also recognized as having a larger cranium than his contemporaries.

Homo ergaster

The almost perfectly preserved skeleton of the "Turkana Boy" is one of the most spectacular discoveries in paleoanthropology. Judging from his anatomy, scientists believe this Homo ergaster was a tall youth about 13 to 15 years old. According to research, the boy died beside a shallow river delta, where he was covered by alluvial sediments. Comparing the shape of the skull and teeth, H. ergaster had a similiar head structure to the Asian Homo erectus.

Homo heidelbergensis

This adult male, Homo heidelbergensis, was discovered in in Sima de los Huesos, Spain in 1993. Judging by the skull and cranium, scientists believe he probably died from a massive infection that caused a facial deformation. The model, shown here, does not include the deformity. This species is believed to be an ancestor of Neanderthals, as seen in the shape of his face. "Miquelon," the nickname of "Atapuerca 5", lived about 500,000 to 350,000 years ago and fossils of this species have been found in Italy, France and Greece.

Homo neanderthalensis

The "Old Man of La Chapelle" was recreated from the skull and jaw of a Homo neanderthalensis male found near La Chapelle-aux-Saints, in France in 1908. He lived 56,000 years ago. His relatively old age, thought to be between 40 to 50 years old, indicates he was well looked after by a clan. The old man's skeleton indicates he suffered from a number of afflictions, including arthritis, and had numerous broken bones. Scientists at first did not realize the age and afflicted state of this specimen when he was first discovered. This led them to incorrectly theorize that male Neanderthals were hunched over when they walked.

Homo floresiensis

The skull and jaw of this female "hobbit" was found in Liang Bua, Flores, Indonesia, in 2003. She was about 1 meter tall (about 3'3") and lived about 18,000 years ago. The discovery of her species, Homo floresiensis, brought into question the belief that Homo sapiens was the only form of mankind for the past 30,000 years. Scientists are still debating whether Homo floresiensis was its own species, or merely a group of diseased modern humans. Evidence is mounting that these small beings were, in fact, a distinct human species.

Homo sapiens

Bones can only tell us so much. Experts often assume or make educated guesses to fill in the gaps in mankind's family tree, and to develop a sense what our ancestors may have looked like. Judging from skull and mandible fragments found in a cave in Israel in 1969, this young female Homo sapien lived between 100,000 and 90,000 years ago. Her bones indicate she was about 20 years old. Her shattered skull was found among the remains of 20 others in a shallow grave.