The Siberian "Atlantis" Beringia is a genetic trail about the lives, food, housing, and tools of the of ancestors of Native Americans paused en route from Asia living for 10,000 years on the Bering land bridge. Genetic and environmental evidence indicates that after the ancestors of Native Americans left Asia, they spent 10,000 years in shrubby lowlands on a broad land bridge that once linked Siberia and Alaska. Archaeological evidence is lacking because it drowned beneath the Bering Sea when sea levels rose. Check out the article, "Welcome to Beringia," in the February 28, 2014 issue of the journal Science.
In past years, archaeologists once considered Beringia, a highway that led migrations of people from Siberia to Canada and what today is Alaska and 'trails' along the Western coast of the rest of what's now the USA, Central, and South America. The presently partly submerged landmass once stretched from Siberia to northern Canada. Now, a flurry of studies suggests that this lost world could have been an ice age haven, dotted with game and wildflowers, for both animals and humans.
According to one model, the ancestors of today's Native Americans may have stayed in Beringia for thousands of years before coming to the Americas
University of Utah anthropologist Dennis O'Rourke and two colleagues make that argument in the Friday, February 28, 2014 issue of the journal Science. They seek to reconcile existing genetic and paleoenvironmental evidence for human habitation on the Bering land bridge – also called Beringia – with an absence of archaeological evidence.
O'Rourke says cumulative evidence indicates the ancestors of Native Americans lived on the Bering land bridge "in the neighborhood of 10,000 years," from roughly 25,000 years ago until they began moving into the Americas about 15,000 years ago once glacial ice sheets melted and opened migration routes, according to the February 27, 2014 news release, "10,000 years on the Bering land bridge."
The map you see in the image with this article shows the outlines of modern Siberia (left) and Alaska (right) with dashed lines. The broader area in darker green (now covered by ocean) represents the Bering land bridge near the end of the last glacial maximum, a period that lasted from 28,000 to 18,000 years ago when sea levels were low and ice sheets extended south into what is now the northern part of the lower 48 states. University of Utah anthropologist Dennis O'Rourke argues in the Feb. 28, 2014 issue of the journal Science that the ancestors of Native Americans migrated from Asia onto the Bering land bridge or "Beringia" some 25,000 years ago and spent 10,000 years there until they began moving into the Americas 15,000 years ago as the ice sheets melted.
University of Utah anthropologist Dennis O'Rourke co-authored a Perspective column in the journal Science arguing that genetic, ancient environmental and archaeological evidence can be reconciled in support of the idea that the ancestors of Native Americans spent some 10,000 years living in brushy refuges on the Bering land bridge en route from Siberia to the Americas. Contrary to common misperception, the "bridge" really was a landmass 1,000 miles wide from north to south and covered most of the area now shown as ocean on the map around, behind and above O'Rourke's head.
O'Rourke co-authored the Science Perspective column – titled "Out of Beringia?" – with archaeologist John Hoffecker of the University of Colorado at Boulder, and Scott Elias, a paleoecologist at the University of London. Perspective columns in Science don't feature research by the authors, but instead are meant to highlight and provide context for exciting new research in a field or across fields
"Nobody disputes that the ancestors of Native American peoples came from Asia over the coast and interior of the land bridge" during an ice age called the "last glacial maximum," which lasted from 28,000 to at least 18,000 years ago, O'Rourke says, according to the news release, "10,000 years on the Bering land bridge."
The ice sheets extended south into the Pacific Northwest, Wyoming, Wisconsin and Ohio
Large expanses of Siberia and Beringia were cold but lacked glaciers. The absence of archaeological sites and the inhospitable nature of open, treeless landscape known as tundra steppe mean that "archaeologists have not given much credence to the idea there was a population that lived on the Bering land bridge for thousands of years," he adds, according to the news release.
O'Rourke and colleagues say that in recent years, paleoecologists – scientists who study ancient environments – drilled sediment cores from the Bering Sea and Alaskan bogs. Those sediments contain pollen, plant and insect fossils, suggesting the Bering land bridge wasn't just barren, grassy tundra steppe but was dotted by "refugia" or refuges where there were brushy shrubs and even trees such as spruce, birch, willow and alder.
"We're putting it together with the archaeology and genetics that speak to American origins and saying, look, there was an environment with trees and shrubs that was very different than the open, grassy steppe. It was an area where people could have had resources, lived and persisted through the last glacial maximum in Beringia," O'Rourke says in the news release. "That may have been critical for the people to subsist because they would have had wood for construction and for fires. Otherwise, they would have had to use bone, which is difficult to burn."
A Frozen, Isolated Dawn for the Earliest Americans
During the last glacial maximum, thick glacial ice sheets extended south into what now is the northern United States, sea levels dropped some 400 feet, O'Rourke says, according to the news release. As the glaciers melted, sea levels began to rise, reaching current levels 6,000 years ago.
During the long glacial period, Siberia and Alaska were linked by the Bering land bridge, which contrary to the name's implication, really was a huge swath of land north, between and south of Siberia and Alaska, at the present sites of the Chukchi Sea, the Bering Strait and the Bering Sea, respectively.
At its largest extent, Beringia measured as much as 1,000 miles from north to south and as much as 3,000 miles from Siberia's Verkoyansk Range east to the Mackenzie River in in Canada
The theory that humans inhabited the Bering land bridge for some 10,000 years "helps explain how a Native American genome (genetic blueprint) became separate from its Asian ancestor," O'Rourke says, according to the news release.
"At some point, the genetic blueprint that defines Native American populations had to become distinct from that Asian ancestry," he explains. "The only way to do that was for the population to be isolated. Most of us don't believe that isolation took place in Siberia because we don't see a place where a population could be sufficiently isolated. It would always have been in contact with other Asian groups on its periphery. But if there were these shrub-tundra refugia in central Beringia, that provided a place where isolation could occur due to distance from Siberia," O'Rourke says in the news release.
Genetic and Paleoenvironmental Evidence
O'Rourke and colleagues point to a study of mitochondrial DNA – genetic information passed by mothers – sampled from Native Americans throughout the Americas. The study found that the unique genome or genetic blueprint of Native Americans arose sometime before 25,000 years ago but didn't spread through the Americas until about 15,000 years ago.
"This result indicated that a substantial population existed somewhere, in isolation from the rest of Asia, while its genome differentiated from the parental Asian genome," O'Rourke says, according to the news release. "The researchers suggested Beringia as the location for this isolated population, and suggested it existed there for several thousand years before members of the population migrated southward into the rest of North and, ultimately, South America as retreating glaciers provided routes for southern migration."
"Several other genetic-genomic analyses of Native American populations have resulted in similar conclusions," he adds. "For a long time, many of us thought the land bridge was a uniform tundra-steppe environment" – a broad windswept grassland devoid of shrubs and trees," O'Rourke says in the news release. "But in recent years, sediment cores drilled in the Bering Sea and along the Alaskan coast – the now-submerged lowlands of Beringia – found pollens of trees and shrubs."
Beringia was a patchwork of environments that served as a refugia for a population
That "suggests Beringia was not a uniform tundra-steppe environment, but a patchwork of environments, including substantial areas of lowland shrub tundra," O'Rourke says, according to the news release. "These shrub-tundra areas were likely refugia for a population that would be invisible archaeologically, since the former Beringian lowlands are now submerged."
"Large herd animals like bison or mammoths likely lived on the highland steppe tundra because they graze. Many smaller animals, birds, elk and moose (which browse shrubs instead of grazing on grass) would have been in the shrub tundra," he adds, according to the news release.
Other research indicates "that much of Beringia – particularly the lowlands – appears to have had average summer temperatures nearly identical (or only slightly cooler in some regions) to those in the region today," O'Rourke says, according to the news release. "The local environments likely were not as daunting as many have assumed for years. They probably hunkered down pretty good in the winter though. It would have been cold."
The idea that rising sea levels covered evidence of human migration to the Americas has long been cited by researchers studying how early Native Americans moved south along the Pacific coast as the glaciers receded and sea levels rose.
O'Rourke says the idea hasn't been used before to explain the scarcity of archaeological sites in Alaska and Siberia, which were highlands when the land bridge was exposed. But O'Rourke and his colleagues say archaeological sites must be found in Beringia if the long human layover there is to be confirmed. Although most such sites are underwater, some evidence of human habitation in shrub tundra might remain above sea level in low-lying portions of Alaska and eastern Chukotka (in Russia)."
Radioactive wolves inhabit vacant homes
As far as recent culture and history moves, it took a nuclear reactor accident to bring the animal, especially the thriving wolf population back to Chernobyl. Should the US take note of what happens to an area when that place is deserted by humans due to an accident? See the three-part video, Wolf Battlefield : What life is really like for the Wolf Pack in the wild. (Video).
What happens to nature after a nuclear accident? And how does wildlife deal with the world it inherits after human inhabitants have fled? People looking for healthier environments such as wildlife parks to explore, can take a lesson just by looking at how the animals reclaimed the city when the people left.
What happened is that back in 1986 the world witnessed a nuclear meltdown at the infamous Chernobyl power plant in present-day Ukraine. The accident left miles of land in radioactive ruins.
The first animals to take over were the bison herds and then the wolves....So that the land began to look as it did just after the end of the last ice age. Residents living in areas most contaminated by the disaster were evacuated and relocated by government order.
Today, there's a no-man’s land human making that is now left to its own devices. That land will be radioactive for thousands of years. But has it changed the animal life? Not in many measurable ways, so far, say scientists. The wolves are healthy, at least for now, and so are the other animals--eagles, bison, horses, beavers, various birds, moose, and other animals looking much as they did before humans plowed the land.
In the ensuing 25 years, forests, marshes, fields and rivers reclaimed the land, reversing the effects of hundreds of years of human development, according to the Radioactive Wolves blog page.
For the animals, this radiation-wracked exclusion zone, or “dead zone,” has become a kind of post-nuclear wolf Eden, populated by beaver and bison, horses and birds, fish and falcons – and ruled by wolves.
Looks like wolves are kings in that land, in spite of the cold winters between Belarus and the Ukraine. The Belarus side is where the no-radio zone lies and the Ukraine side is radioactive. The wolves cross back and forth between the rivers that separate the two nations.
Access to the radioactive zone is now permitted, at least on a limited basis. So scientists are monitoring the surviving wildlife in the area, trying to learn how the various species are coping with the invisible blight of radiation.
So what makes the wolves kings over the bison? They're the top predators in this new wilderness. According to scientists, wolves best reflect the condition of the entire ecosystem because if the wolves are doing well, the populations of their prey must also be doing well.
Scientists put collars on the wolves, monitor their travels, give physical exams to the newborn wolves, and monitor their health. Check out the key long-term study of the wolves. Scientists want to find out more about the wolves' health, range, and numbers.
In the PBS video, Radioactive Wolves discusses the state of wildlife populations in Chernobyl’s exclusion zone, an area that, to this day, remains too radioactive for human habitation. For those interest in health, it shows what happens when humans leave an area, the place becomes green with plant life, and the animals appear to thrive without intrusion from humans on their habitats.
You don't need a nuclear accident to restore living space for animals. There are parks, but space is tight. At least for the wolves, they seem to be getting back to their former glory as the area around Belarus and Ukraine formerly had one of the largest wolf populations in the world. Some villages still carry the name "howling wolf."
If you live near the wolf zones on the non-radioactive side, you may hear the howling all night. And since no humans are living on the radio-active side, the animals are free to make as much noise as they want. Apparently, there is no shortages of food, and the wolves have taken up residence in the houses formerly occupied by people. To their health, sometimes the wolves are toasted. Beaver plays a large part of the wolves' food sources.