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Did Denisovans walk to North America?



For a person from a 41,000-year-old fossil bone finger from a nine-year-old girl, with a bracelet he wore, was (until recently) the only proving known artifacts, the mysterious Denisovans have certainly received much publicity. Both scholarly journals and popularly oriented science magazines are quickly taken into any academic or theoretical news from the fields of anthropology and archeology tied to them in some way or another. Artifacts were discovered in the 1970's by Soviet paleontologist Nicolai Ovodov.

Although the name assigned to the group has its origin in a somewhat spiritually, rather than a conventional way. Denis Hermit is a Russian Orthodox religious contemplative living in a cave named for him on 1

8 th Century. The cave is located in the Altai Mountains of Central Siberia, not far from where the borders of Russia, Mongolia, and China meet. Denis was formerly before, the other first people made a cave at home, and recently, sheep shepherds hired it.

Denisovans' Origin

However, the first speculation about the Denisovans came long before they were given their name, and many miles to the east, as scholars decided that they belonged to the Balkans, Ukraine, and Kazakhstan. Why? Anthropologists seem to notice that the fossils and artifacts of Neanderthal are always found in Western Europe and in the Middle East.

Some reasons that Neanderthals or some similar citizens are logically owned by the east and northeast of these areas too, and now, with Denisovan's search, this may be the case. In fact, to some scientists and ancient citizens, the Neanderthals and Denisovans have been & # 39; cousins ​​& # 39 ;.
Their origins are dated to around 300,000 BC years, when Homo sapiens and Neanderthals both emerge from Africa during a pluvial season caused by a continental glacier covering most of Europe. This wetter provides most of North Africa with a friendly environment. With the majority of the world's water locked on ice in Europe, Siberia, North America, and Antarctic, the Mediterranean waters and Red Seas allow the first Neanderthals, then Homo sapiens, also known as Cro Magnon Man, walks in the dry point.

Neanderthals, since the discovery of their fossils in late 19 th Century, are characterized as cruel, more primitive than Homo sapiens, some scholars claim sub- human status and lack of language skills for them.

The famous eyebrows of their skull contributed to this view, as they also had bonobos, chimpanzees, and gorillas. The ancient textbooks claim that subsequent waves of Homo sapiens came to the scene, two species of animals were stacked, gradually firing on the unlucky Neanderthals.

After 21 century st mistaken. Hybrid fossils from the interbreeding of the two species have been discovered and revealed by genetics that many modern Homo sapiens contain small levels of Neanderthal genes. Early arrivals in Europe have not been eliminated after all but have been assimilated.

  Hybrid fossils show interbreeding between Homo sapiens and Neanderthals. (Abuk SAW / CC BY-SA 3.0)

Hybrid fossils show interbreeding between Homo sapiens and Neanderthals. (Abuk SAW / CC BY-SA 3.0 )

Far further in the East, scientific speculation is also focused. In the 1980's in the Tibetan Plateau, a Buddhist monk investigating a karstic cave found an adult jaw bone with similarity to the fossils of Neanderthals. Relics were replaced by researchers at Northern China University, which followed its protein to determine the age of 160,000 years BC. These scholars said to be Denisovan.

It is placed at the height of the last glacial, or Wisconsin epoch, which makes it more ancient than the fingers of the little girl, dated when the continental glaciers begin to descend.

Denisovan Migration

Today, different scientists have said about Denisovan's migration routes, which assumed they moved south-east, from mainland Asia to Indonesia, Papua New Guinea, the neighboring Melanesian Island, and possibly even Australia. Routes of migration like these have become true, because as the continental glaciers are at their height, sea levels may be low enough to facilitate dry land travel.

  The evolution and geographic spread of Denisovans vs. Neanderthals, Homo heidelbergensis, and Homo erectus. (Cmglee / CC BY-SA 3.0)

The evolution and geographic spread of Denisovans vs. Neanderthals, Homo heidelbergensis, and Homo erectus. (Cmglee / CC BY-SA 3.0 )

When glaciers are the largest, covering the vast expanses of the vast land area, and even many parts of the high range of the mountain in the lower latitudes region, easier. People can walk now between what the islands are in hotter times. Scientists have discovered where the shores are located at different times in the past history, both by estimating the former glacial dimensions and finding evidence of the decline of the sea and displacement. This data, when applied to areas separated from water from each other, such as Morocco from Spain / Gibraltar, Tunisia from Sicily and Italy, or Southeast Asia from the Philippines, Indonesia and Australia , shows where ancient migrations occurred and almost when.

A special case arises when sea level changes are applied to northeastern Siberia and from northwestern North America. Here we have glaciers that sometimes prevent the transit routes, certainly not the case in North Africa / Southern Europe or in the south-eastern Asia / Pacific archipelagos or Australia. These transit routes are located in relatively warm climates where ice does not form.

Enter the Beringia, the landmass that once existed during the glacial period when major parts of the Asian and Alaskan continental shelf shelters, now under the Arctic Ocean, were dry land. In their south, most of the Bering Sea, including the arch of the island stretches from the Kodiak Peninsula of Alaska through the Aleutian and Komandorski Islands, to the northern Kamchatka Coast.

  Beringia, the landmass that exists during glacial times is dry ground. (Luke Gojda / Adobe)

Beringia, the landmass that exists during glacial times is dry ground. (19659011) Lukas Gojda / Adobe)

When Beringia is not blocked by ice (during glaciers either form or melts) Beringia is the land bridge for humans and animals to enter North America from Asia. It will also be a bridge for backward migrations, little later in geologic time.

When glaciers disappeared, except Greenland and Antarctica, as they are today, a small rest of Beringia is still a bridge for people, because the two Diomede Islands, one of the United States, one in Russia, is seen from every country. In more recent times, when the first person has mastered the boat-making and ocean navigation technology, his land vision on the horizon has led to the transfer of water.

Today, natives of natives and scientists of American Americans tell ancient myths to cross the water from an old land to the new one. However, later, the Denisovans had disappeared.

How many years ago were the great continental glaciers in the right size and the sea levels were just the right height for people to cross the Beringia by foot?

  Range of Beringia during Denisovan. (Roblespepe / Public Domain)

Range of Beringia during Denisovan. (Roblespepe / Public Domain )

All glaciologists, geologists, climatologists, and anthropologists have all the hands to estimate the age, magnitude, and magnitude of so-called glacial epochs and the warmer interludes between them. Current thinking is dating dating before any type of life, there are nine called glacial ages. We still have the present, often called Pleistocene Epoch, which started about 2,600,000 BC. In it there are at least eleven interglacial or warmer seasons, which last approximately ten to thirty thousand years each.

The next last one, sometimes called Eemian Interglacial, lasted nearly 130,000 to 115,000 years BC. It is warmer than the warmer days, often called Late Cenozoic Interglacial or Holocene, which are still ongoing. At the height of Eemian, the palm trees grew up north as the Alaskan Panhandle. The Late Cenozoic period starts around 15,000 BC and as everyone knows the political discussions and debates knows, it still keeps getting hotter.

  During the Eemian period, palm trees grew in Alaskan Panhandle. (freedom_wanted / Adobe)

During Eemian period, palm trees grew in Alaskan Panhandle. (freedom_wanted / Adobe)

When both Eemian and Late Cenozoic dates are applied to human transfers, some observational hypotheses suggest themselves. In tropical and sub-tropical latitudes only marine levels are related because glacial blockage is not a major factor, while in Beringia, both subtropical climates and glacial blockage also have obstacles. However, in Late Cenozoic alone, the evolution of human culture has led the use of boats to the landscape thus slashing the barriers created by rising sea levels. This factor is largely applied in areas where early people can look to the ground on the horizon so risking pushing forward.

Denisovan DNA in America

While both scientists and hobbyists like the early people lore are speculating about who, when, and how people crossed Beringia from Asia to North America, others like ilk is pursuing difficult answers. Geneticists are busy pushing DNA boundaries and protein analysis further and further, while earlier radio, strontium, and oxygen-18 radio technologies can only be used in limited situations. Language anthropologists began to compare languages ​​using computer techniques and tribal legends more seriously.

Aerial photography and satellite imagery find a way to archeology. Now it's time to ask for almost a horrible question for some, "Did Denisovans do it in North America?" Or otherwise, the traces of their DNA will open to the citizens of the New World, as found Neanderthal DNA in the genes of some modern Europeans?

At first, scholars and hobbyists alike assumed human migration by Beringa occurred only during the Late Cenozoic, during which three distinct migration currents were identified. Then there are two additional factors that indicate that the Eemyan period should also see some activity. (1) Scrub crops growing in Beringia during the cooler Late Cenozoic are not supported by large grazing animals such as mammoths, mastodons, horses, and camels that are sometimes grown in the Americas.

Researchers like David Reich of Harvard Medical School and his colleagues suggested that a 40,000-year negative selection of Neanderthal and Denisovan genes has existed in many Southeast Asians and Pacific Islands. Will there be time for DNA influences to be taken away from Western Hemisphere from the arrivals of Cenozoic that arrived at Beringa? The same scientist also found Denisovan gene in the Americas and far north-east Asia.

  Pleistocene Tools discovered in Calico Early Man Site. (Travis / CC BY-SA 2.0)

Pleistocene Tools discovered on the Calico Early Man Site. (19659012)

Other scientists, while not concerned with Denisovans or DNA evidence, have proven far south of Beringia in the same North and South America have suggested the existence of a person dated earlier than the Late Cenozoic. While not yet fully verified, the Calico site in California is alleged to date in early 200,000 BC. If this proves to be accurate, it is highly suggested that some people cross the Beringia during the third-last interglacial warming period. While not specific dates are mentioned, famous archaeologist Louis Leakey is one of the scientists claiming Calico is a bona fide early human site.

Chile, in all areas, has many related sites of the first person. Monte Verde in central Chile containing fossils and a human footprint, was dated to 18,500 BC, putting it about 2,500 years before Beringia was available for Old Cenozoic migrants. Other Chilean investigators have made claims for fossil remains of agricultural-type planted crop rows. Many Denisovans scholars have long been making a case for the fact that if the early Late Cenozoic had been made throughout Beringia, it would have been a long time for their descendants to travel south of South America to occupy the sites there, giving of verified dates for sites. In other words, their ancestors should come during the Eemian period.

Migrants who cross the Beringia cross over during the Late Cenozoic, we find that they are divided into three different, relatively unlike groups. More genetic research is required before being had and who has not had some Denisovan gen is known. The last of the three, the Athabascans, sometimes called Na Dene, are still moving south when the first European colonists are arriving in the north south of North and South America. While some Athabascans remained in Alaska or Yukon, others pushed Arizona, New Mexico, and northern Mexico, where they are today, known as the Navajo and Apache tribes. All New World Athabascans have a cultural and genetic approach to Chukchi in far eastern Siberia.

If any Denisovans belong to groups that cross the Beringia, it must be in the Eemian period. Late Cenozoic appears to be late and the third-last interglacial period is probably too early, or otherwise, too fuzzy to make any decisions. Even though their DNA crossed the bridge, as part of the living bodies of humans whose ancestors were mated to Denisovans, the answer should be "yes." What does not know, details – who includes whom, where, and when.

It's just a fascinating story of people who almost & # 39; ape boys & # 39; and & # 39; monkey women & # 39 ;, and are now emerging as another important piece in the puzzle that forms the story of human civilization.

Top image: Finger bone fragment containing Denisovan DNA. Source: Thilo Parg / CC BY-SA 3.0 .

By Glenn Dahlem, Ph.D


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