FIRST AMERICANS: DNA, ASIA AND ASIANS

DNA EVIDENCE SAYS FIRST AMERICANS CAME FROM ASIA

Beringia in the Ice Age

Natives Americans are believed to have descended from Asian people who arrived in North America via the Bering Strait. The DNA of ancient American bog people is closer to the Japanese than Americans.

Glenn Hodges wrote in National Geographic: “In recent years geneticists have compared the DNA of modern Native Americans with that of other populations around the world and concluded that the ancestors of Native Americans were Asians who separated from other Asian populations and remained isolated for about 10,000 years, based on mutation rates in human DNA. During that time they developed unique genetic signatures that only Native Americans currently possess. [Source: Glenn Hodges, National Geographic, January 2015 /~]

“These genetic markers have been found not only in the DNA recovered from Naia’s skeleton” from Hoyo Negro, Mexico “ but also in the remains of a child buried some 12,600 years ago in western Montana, on a piece of land now called the Anzick site.” In 2014 “Danish geneticist Eske Willerslev reported that an analysis of the child’s remains had yielded, for the first time, a full Paleo-American genome. “Now we’ve got two specimens, Anzick and Hoyo Negro, both from a common ancestor who came from Asia,” Waters says. “And like Hoyo Negro, the Anzick genome unquestionably shows that Paleo-Americans are genetically related to native peoples.” Though some critics point out that two individuals are too small a sample to draw definitive conclusions, there’s strong consensus on the Asian ancestry of the first Americans.” /~\

Genetic Model of the First Americans

Laura Geggel wrote in Live Science: Geneticists studying the first Americans tend to paint a more consistent picture than archaeologists do, mainly because they're using the same human remains and genetic datasets. Genetic analyses have found that Ancient North Siberians and a group of East Asians paired up around 20,000 to 23,000 years ago, Jennifer Raff, an associate professor of anthropology at the University of Kansas, told Live Science. Soon after, the population split into two genetically distinct groups: one that stayed in Siberia, and another, the basal American branch, which emerged around 20,000 to 21,000 years ago. Genetic data suggest the descendants of this basal American branch crossed the Bering Land Bridge and became the first Americans. [Source: Laura Geggel, Live Science, October 9, 2023]

The basal American branch then split into three groups: unsampled population A (UPopA), a mysterious "genetic" ghost that has "only been detected indirectly from the genomes" of the Mixe, of what is now Mexico, Raff said; Ancient Beringians, who have no known living descendants; and Ancestral Native Americans (ANA), whose descendants live on today.

All three of these groups ultimately made it to North America, but their diverging genetics suggests that they crossed in separate movements, Meltzer and Willerslev wrote in the review. Some didn't make it very far; The Ancient Beringians entered Alaska but never made it south of the continental ice sheets. The last known Ancient Beringian, known as the "Trail Creek individual," died around 9,000 years ago in Alaska.

Meanwhile, the ANA lineage underwent several splits, suggesting that these people settled in different areas of North America as they had limited gene flow between them, Raff said. There was one split between 21,000 and 16,000 years ago and then a second one around 15,700 years ago. During this second split, the Northern Native Americans — whose living descendants include speakers of the Algonquian, Salishan, Tsimshian and Na-Dené language groupings — separated from the Southern Native Americans (SNA), who spread southward and whose descendants include the Clovis, Raff said. Every known living and deceased Indigenous "individual south of Canada belongs to SNA," Raff said.

DNA Studies Related to the First Americans

One study revealed that the first Native American group to settle in the Americas had just about 250 people in it. According to Live Science: To make the finding, researchers looked at the DNA of people from Native American groups in Central and South America, different Siberian groups, and people from China. Because genetic divergence (for instance, between Native Americans and Siberians) increases with time, the researchers were able to plug the DNA data into a computer model and work backward to determine the size of the original group. [Source: Laura Geggel, Live Science, December 25, 2018]

Eske Willerslev of the University of Cambridge and the Center for GeoGenetics at the Globe Institute at the University of Copenhagen sequenced the first ancient human genome in 2010 and later sequenced numerous genomes in an effort to get a picture of the first Americans, including a 12,400-year-old boy from Montana, 11,500-year-old infants at Alaska’s Upward Sun River site and the skeletal DNA of a boy whose 24,000-year-old remains were found at the village of Malta, near Russia’s Lake Baikal. [Source: Fen Montaigne, Smithsonian magazine, January-February 2020]

Fen Montaigne wrote in Smithsonian magazine: “According to Willerslev, sophisticated genomic analyses of ancient human remains — which can determine when populations merged, split or were isolated — show that the forebears of Native Americans became isolated from other Asian groups around 23,000 years ago. After that period of genetic separation, “the most parsimonious explanation,” he says, is that the first Americans migrated into Alaska well before 15,000 years ago, and possibly more than 20,000 years ago. Willerslev has concluded that “there was a long period of gene flow” between the Upward Sun River people and other Beringians from 23,000 to 20,000 years ago. “There was basically an exchange between the populations across eastern and western Beringia,” Willerslev said in a phone interview from Copenhagen. “So you had these groups hanging around Beringia and they are to some degree isolated — but not completely isolated — from each other. You had those groups up there, on both sides of the Bering Land Bridge, around 20,000 years ago. I think that is very likely.”

Chinese researchers Feng Zhang, Bing Su, Ya-ping Zhang and Li Jin have done studies based on Mitochondrial DNA (mtDNA), circular chromosomes found inside cellmitochondria that is passed down on along the female line. They wrote in an article published by the Royal Society: Among Native Americans: “There are three linguistically identified groups of population: Amerind, Eskimo-Aleut and Na-Dene. mtDNA haplogroups of Native America include four Asian haplogroups (A, B, C and D) and one European haplogroup studied Amerind populations and showed that the sequence diversity of haplogroup B is much lower than those of haplogroups A, C and D. Furthermore, haplogroup B is absent in Siberia, while A, C and D are prevalent. These two observations imply that the Amerind linguistic group might have been derived from two migrations. [Source: “Genetic studies of human diversity in East Asia” by 1) Feng Zhang, Institute of Genetics, School of Life Sciences, Fudan University, 2) Bing Su, Laboratory of Cellular and Molecular Evolution, Kunming Institute of Zoology, 3) Ya-ping Zhang, Laboratory for Conservation and Utilization of Bio-resource, Yunnan University and 4) Li Jin, Institute of Genetics, School of Life Sciences, Fudan University. Author for correspondence (ljin007@gmail.com), 2007 The Royal Society ***]

Lell et al. (2002) analysed 12 Y-SNPs in 549 individuals from Siberia and the Americas. Three major Y lineages of Native American populations have been found: M3 (66 percent), M45 (25 percent) and M130 (5 percent). M3, also known as DYS119 (Underhill et al. 1996), was confined to the Chukoka peninsula in Siberia. M45 was divided into two subgroups; one subgroup (M45a) is found throughout the Americas, and another (M45b) is prevalent in North and Central America. These two sub-haplogroups have different distribution patterns in Siberia (M45a in middle Siberia and M45b in eastern Siberia). The C-M130 haplogroup has a similar distribution to that of M45b in Siberia and in North America. They hypothesized that there were two independent migrations into America from Siberia, which is consistent with the mtDNA evidence (Wallace et al. 1985). M242 is a polymorphism, which was introduced after M74 (arising in Asia) but before M3 (arising in America) in the phylogeny of the human Y chromosome (Underhill et al. 1996, 2000), and can be used to date the entry into the Americas. Based on the diversity of 15 Y-STRs in 69 Eurasian M242-T samples, the time of first entry into the Americas was estimated to be close to 15 000–18 000 years BP (Seielstad et al. 2003).

Did the First Americans and Japanese Come from China?

A DNA study published in May 2023 in Cell Reports revealed that some of the first arrivals in America came from China during two distinct migrations: the first during the last ice age, and the second shortly after. "Our findings indicate that besides the previously indicated ancestral sources of Native Americans in Siberia, the northern coastal China also served as a genetic reservoir contributing to the gene pool," Yu-Chun Li, one of the report authors, told AFP. [Source: Issam Ahmed, AFP, May 10, 2023]

AFP reported: Li added that during the second migration, the same lineage of people settled in Japan, which could help explain similarities in prehistoric arrowheads and spears found in the Americas, China and Japan. It was once believed that ancient Siberians, who crossed over a land bridge that existed in the Bering Strait linking modern Russia and Alaska, were the sole ancestors of Native Americans. More recent research, from the late 2000s onwards, has signaled more diverse sources from Asia could be connected to an ancient lineage responsible for founding populations across the Americas, including Bolivia, Brazil, Chile, Ecuador, Mexico and California. Known as D4h, this lineage is found in mitochondrial DNA, which is inherited only from mothers and is used to trace maternal ancestry.

The team from the Kunming Institute of Zoology embarked on a ten-year hunt for D4h. Charles Q. Choi wrote in Live Science: The researchers analyzed more than 100,000 contemporary and 15,000 ancient DNA samples from across Eurasia. D4h is a rare mitochondrial DNA lineage which is currently found in only about 1 in 200 people worldwide. "This genetic type had only been sporadically reported in different studies," study lead author Yu-Chun Li, a molecular anthropologist at the Kunming Institute of Zoology in China, told Live Science. "Therefore, this female lineage, as well as its origin and dispersal history — especially its dispersal into the Americas — gained little attention until now." Previous research found that one branch of D4h, known as D4h3a, was seen in Indigenous Americans, while another offshoot named D4h3b was detected in China and Thailand. This suggested that ancient members of the D4h lineage might help bridge Asia and the Americas."The most difficult work was to collect as many samples belonging to D4h as we could," study senior author Qing-Peng Kong, an evolutionary geneticist at the Kunming Institute of Zoology, told Live Science. [Source: Charles Q. Choi, Live Science May 10, 2023]

The Kunming team eventually landed on 216 contemporary and 39 ancient individuals who came from the ancient lineage. By analyzing the mutations that had accrued over time, looking at the samples' geographic locations and using carbon dating, they were able to reconstruct the D4h lineage's origins and expansion history. The results revealed two migration events. The first was between 19,500 and 26,000 years ago during the Last Glacial Maximum, when ice sheet coverage was at its greatest and climate conditions in northern China were likely inhospitable.

The second occurred during the melting period, between 19,000 and 11,500 years ago. Increasing human populations during this period might have triggered migrations. In both cases, the scientists think the travelers were seafarers who docked in America and traveled along the Pacific coast by boats. This is because a grassy passageway between two ice sheets in modern Canada, known as the "inland ice-free corridor," was not yet opened.In the second migration, a subgroup branched out from northern coastal China to Japan, contributing to the Japanese people, especially the indigenous Ainu, the study said, a finding that chimes with archeological similarities between ancient people in the Americas, China and Japan.

Li said a strength of the study was the number of samples they discovered, and complementary evidence from Y chromosomal DNA showing male ancestors of Native Americans lived in northern China at the same time as the female ancestors, made them confident of their findings.Loren Davis, an archaeologist at Oregon State University in Corvallis who did not take part in this research, told Live Science while the new study is exciting, it's just "another piece of the puzzle," on how and when ice age humans first populated the Americas, Davis said. For instance, the researchers stressed that while these new findings suggest this single northern Chinese lineage may have contributed to Indigenous American ancestry, "it does not represent the whole history of all Native Americans," Li said. "Investigating other lineages showing genetic connections between Asia and the Americas will help obtain the whole picture of the history of Native Americans."

Migration Patterns Deduced from Blood Types and North America and Siberian Languages

Geneticists believe that early Americans were composed of three separate groups that arrived in America at different times from different places: 1) the Amerind, the dominate group in North and South America, possess only type O blood; 2) the Na-Dene, who live in clusters in Alaska, Canada and part of the U.S. Southwest, have mostly O but a little A blood; and 3) the Alaskan and Canadian Inuit (Eskimo) have A, B, AB and O blood group patterns which parallel other groups found in the rest of the world.

Joseph Stromberg wrote in smithsonian.com: “A pair of linguistics researchers, Mark Sicoli and Gary Holton, recently analyzed languages from North American Na-Dene family (traditionally spoken in Alaska, Canada and parts of the present-day U.S.) and the Asian Yeneseian family (spoken thousands of miles away, in central Siberia), using similarities and differences between the languages to construct a language family tree. As they note in an article published today in PLOS ONE, they found that the two language families are indeed related—and both appear to descend from an ancestral language that can be traced to the Beringia region. Both Siberia and North America, it seems, were settled by the descendants of a community that lived in Beringia for some time. In other words, Sicoli says, “this makes it look like Beringia wasn’t simply a bridge, but actually a homeland—a refuge, where people could build a life.”[Source: Joseph Stromberg, smithsonian.com, March 12, 2014 ^]

“Sicoli began looking into the relationships between languages to model migration in the region several years ago, when he was with Holton at the University of Alaska (Sicoli is now at Georgetown University). The relationship between Yenesian and Na-Dene languages—which would theoretically serve as proof that Native Americans’ ancestors had migrated from Asia—was proposed as far back as 1923, by Italian linguist Alfredo Trombetti, but the first rigorous research to prove the link was only conducted over the past decade or so. ^

“Sicoli and Holton sought to go a step further: They wanted to not only show the two groups were related, but analyze the similarities and differences between languages in the two families to paint a geographic picture of this ancient migration. To do so, they relied upon software programs that conduct phylogenetic analyses. Most often, phylogenetics refers to sorting out the evolutionary relationships between different organisms, using genetic similarities and differences to construct an accurate family tree of species. But because languages, like life, gradually evolve over time, linguists have put the same sort of analysis to work in constructing language trees. ^

“The researchers collected data on two Yeniseian languages, 37 Na-Dene languages and Haida (a language spoken on Canada’s Pacific coast but not believed to be related to Na-Dene, used as a control) from the Alaska Native Language Archive and several other published sources. Then, they used phylogenetic algorithms to create a family tree of the forty languages, determining which were most closely related based on the number of similarities (such as phonemes that serve particular roles in the language’s grammar, for instance). ^

Map of human migrations

“Their tree confirmed that Yenesian and Na-Dene are related—and that Haida is not—but because these languages were carried by populations of humans that were moving over time, the lengths of branches in the tree also allowed Sicoli and Horton to weigh the odds of two different migration hypotheses. The first, proposed by many linguists, held that the source of both the Yenesian and Na-Dene languages was in Asia, with a subset of its speakers migrating across Beringia and bringing evolved versions of the language to North America. The second held that the source was in Beringia itself, with subsets of its speakers fanning out over both Siberia and North America. ^

“The phylogenetic analysis, based on the degree of similarities between Yenesian and Na-Dene languages and within both groups, strongly supported the latter hypothesis—meaning that residents of communities as far apart as Central Siberia and the Great Plains share common ancestors, who likely lived in Beringia for an extended period of time. “Growing up, I’d look at maps showing migrations to the Americas, and they’d always just show arrows going in one direction: straight across from Asia to North America,” Sicoli says. “What we see now is something more complicated, because some of those arrows go back to Siberia, and it wasn’t a non-stop trip.” ^

“This fits with what we know about the geography of the region at the time. Asia and Alaska were connected by a land bridge because global sea levels were much lower, largely because of how much water was locked up in glaciers that covered much more of the planet than today. But even though these glaciers opened up the corridor between North America and Asia, they also closed the door, because, as mentioned before, Alaska itself was under a thick sheet of ice at that time. Thus, the land bridge was a dead end, potentially explaining why these ancient migrants could have spent about 10,000 years in Beringia. Then, about 17,000 years ago, the glaciers began to recede—and sea levels began to rise—providing two reasons to leave Beringia, either for new territory in Alaska or back toward Siberia.”

24,000-Year-Old Siberian DNA Suggests Native Americans More Closely Linked to Eurasians than East Asians

Meeri Kim wrote in the Washington Post: “The genetic analysis of a 24,000-year-old arm bone from an ancient Siberian boy suggests that Native Americans have a more complicated ancestry than scientists realized, with some of their distant kin looking more Eurasian than East Asian. The new study, published in the journal Nature, represents the oldest genome of a modern human ever fully sequenced. [Source: Meeri Kim, Washington Post, November 20, 2013 ||+||]

“Modern-day Native Americans share from 14 to 38 percent of their DNA with the Siberian hunter-gatherers — who are not closely related to East Asians — with the remainder coming from East Asian ancestors. Most scientists have thought that the first Americans came only from the East Asian populations. “If you read about the origins of Native Americans, it will say East Asians somehow crossed the Bering Sea,” said study author and evolutionary biologist Eske Willerslev at Copenhagen University. “This is definitely not the case — it’s more complex than that.” ||+||

“It isn’t known where or when the meeting of the two peoples happened, but a likely location could be Beringia, the region surrounding the current gap between Alaska and Siberia. Although presently occupied by the Bering Strait and its surrounding waters, the glaciers of roughly 20,000 years ago locked up much of the earth’s water, exposing a land bridge between the two continents. The prehistoric crossroad provided an easy way for people, animals and plants to spread. ||+||

“Originally excavated in the 1950s, the remains of the boy had been tucked away in the bowels of a museum in St. Petersburg. He was about 3 when he died, and he was buried with a variety of “grave goods,” including a swan figurine and an ivory pendant. When Willerslev sequenced the DNA from the boy’s upper arm bone, he thought the results were a mistake: It said the boy belonged to a lineage commonly found among Europeans, but not in East Asians. “We put the study on hold for a year because I thought it was contamination,” Willerslev said. They tried again, this time digging deeper and looking at the Y chromosome. It and the rest of the genome told the same story: The boy had links to present-day western Eurasians and Native Americans, but not East Asians. ||+||

“They also sequenced a more recent Siberian adult whose DNA wasn’t as well preserved, and they got similar results. “They were members of a really cosmopolitan group that probably reflect early modern humans leaving Africa and spreading into central Asia,” said study author Kelly Graf, a Texas A&M anthropologist. Their results support fossil evidence from early Paleo-Indian humans, such as a well-preserved skeleton known as Kennewick man found in Washington state. Dated to about 9,000 years old, he has facial features that don’t look East Asian but rather somewhat Caucasian — a mystery found replicated in other skulls. ||+||

“The fact that the first Americans were already mixed to begin with could answer these controversies, Willerslev said. Any Western Eurasian genetic signatures found in Native Americans today were previously attributed to post-1492 colonial mixing with Europeans. “Maybe it has much deeper roots — from Siberia, not Europeans coming over in their boats,” Graf said.” ||+||

Frequency of distribution of the main mtDNA American haplogroups in native Americans

Single Wave Migration Theory Versus Multiple Pulses Theory for the First Americans

There are two theories about the migration process of the first American: 1) it was a single migratory event, the so called single wave theory, or 2) it occurred in multiple pulses, waves or migrations. The evidence gathered so far seems to suggest it was a single event or at least a dominant single event, with some sideshow migrations that didn’t leave much of a DNA impact. Tests on mitochondrial DNA taken from the few examples of ancient American DNA, Joel Achenbach wrote in the Washington Post, “have a genetic marker common today across the Americas, one that scientists say evolved in a prehistoric population that had been isolated for thousands of years in Beringia, the land mass between Alaska and Siberia that formed a bridge between the continents during the Ice Ages. Thus, according to the report, the Native Americans and the Paleoamericans are the same people, descended from the same Beringia population. They just look different because of recent evolution. [Source: Joel Achenbach, Washington Post, May 15, 2014]

“Most scientists have assumed that the first humans to come to the Americas traveled from Eurasia across the Bering land bridge that existed before the oceans rose after the Ice Ages. But there is great debate about whether this represented a single migratory event or multiple pulses of people from different parts of Eurasia and via different routes, including a coastal migration. One maverick theory, based on archeological finds, contends that people came from Europe, following the edge of the ice around the North Atlantic.

“Adding to the mystery is that the Paleoamericans, such as Naia, didn’t look like later Native Americans. Naia had a small, projecting face, with narrow cheekbones, wide-set eyes and a prominent forehead. Native Americans of later millennia tended to have broader, longer, flatter faces, and rounder skulls, said James Chatters, an independent researcher based in Washington state.

Genetic Links Between Early Americans and Early Japanese

Aileen Kawagoe wrote in Heritage of Japan: A 1994 study concluded that ancestral lineages of Ainu people migrated across Beringia carrying HTLV-I virus (subtype A) to the American continent in the Paleolithic era. Phlylogenetic analysis of mitochondrial DNA and HLA type analysis suggest there is a relationship between Japanese and Paleo-Indians in South America (DRB10802 was found to be present in almost all Amerindians, Siberian Eskimos and Japanese Ainu but specifically two Meso and South Amerindian DRB1 alleles – DRB10411 and DRB10417- are also shared with Siberians and Asian Pacific coast populations (Ainu, Japanese and Taiwan) as well as Athabaskans and Eskimos (other First American inhabitants) with the exception of the Aleuts). [Source: Aileen Kawagoe, Heritage of Japan website, heritageofjapan.wordpress.com]

“A 2000 American Scientist article suggested that the “highest frequencies of these four haplogroups occur in the Altai Mountain/Tuva/Lake Baikal region, implying that this general region gave rise to the founders of Native American populations. Otherwise, haplogroup B is absent in the vast majority of native Siberian populations, haplogroup A occurs at very low frequencies outside of Chukotka, and haplogroups C and D are the predominant mtDNA lineages in northern Asia.

“However, the presence of a certain control region mutation in haplogroups C and D may point to alternative source areas for ancestral Native Americans. This mutation appears in the majority of both haplogroup C and D mtDNAs in Native American populations, suggesting it is part of the original sequence motifs for both of them. Among all Asian and Siberian mtDNAs, however, this mutation only appears in haplogroup C mtDNAs from Mongolia and the Amur River region and in haplogroup D mtDNAs in the Japanese, Korean and Ainu. This distribution suggests that East Asia as well as southeast Siberia or Mongolia might be source areas or migration pathways for these haplogroups."

Adachi N, and others in a study of “Mitochondrial DNA analysis of Jomon skeletons” assigned D1a (along with M7a, N9b) to ancient DNA recovered from 16 Jomon skeletons excavated from Funadomari site, Hokkaido, Japan. The fact that Hokkaido Jomons shared haplogroup D1 with Native Americans validates the hypothesized genetic affinity of the Jomon people to Native Americans, providing direct evidence for the genetic relationships between these populations… It appears that the genetic study of ancient populations in northern part of Japan brings important information to the understanding of human migration in northeast Asia and America. Adachi N, and others in “Mitochondrial DNA analysis of Jomon skeletons from the Funadomari site, Hokkaido, and its implication for the origins of Native American“, Am J Phys Anthropol. 2009 Mar;138(3):255-65. doi: 10.1002/ajpa.20923)]

Native American DNA subrace genetic groups

DNA Studies on the Relationship Between North and South Americans

Some studies have suggested that the first Americans diverged genetically from their Siberian and East Asian ancestors about 25,000 years ago. These people traveled across the Bering Strait Land Bridge and eventually split into distinct North and South American populations. By about 13,000 years ago, people of the Clovis culture, known for its use of distinctive, pointy stone tools, came to occupy much of North America. But by this time, people were already living as far south as Monte Verde, Chile. They had been there since a least 14,500 years ago, according to archaeological findings there. Still it is not totally clear how the Clovis culture were linked to populations in South America. [Source: Laura Geggel, Live Science, November 9, 2018]

According to an ancient DNA analysis published online November 8, 2018 in the journal Cell prehistoric people from different populations made their way across the Americas thousands of years ago. People genetically linked to the Clovis culture, one of the earliest and best-known cultures in North America, migrated into South America as far back as 11,000 years ago but then mysteriously disappeared around 9,000 years ago. The 2018 study says that another ancient group of people replaced them, but it is certain how or why this occurred, and the population turnover happened across the entire continent of South America.

Laura Geggel wrote in Live Science: To unravel the genetic mysteries of the these ancient Americans, the researchers reached out to indigenous peoples and government agencies all over Central and South America, asking for permission to study the remains of ancient peoples that have been discovered over the years. In all, the international team of scientists was given permission to do genomewide analyses on 49 ancient people whose remains were unearthed in the following Central and South American countries: Belize, Brazil, Peru, Chile and Argentina. The oldest of these people lived about 11,000 years ago, marking this as a study that takes a big step forward from previous research, which only included genetic data from people less than 1,000 years old, the researchers said.

Their findings showed that DNA associated with the North American Clovis culture was found in people from Chile, Brazil and Belize, but only between about 11,000 to 9,000 years ago. "A key discovery was that a Clovis culture-associated individual from North America dating to around 12,800 years ago shares distinctive ancestry with the oldest Chilean, Brazilian and Belizean individuals," study co-lead author Cosimo Posth, postdoctoral researcher of archaeogenetics at the Max Planck Institute for the Science of Human History in Germany, said in a statement. "This supports the hypothesis that the expansion of people who spread the Clovis culture in North America also reached Central and South America." [In Photos: New Clovis Site in Sonora]

Curiously, around 9,000 years ago, the Clovis lineage disappears, the researchers found. Even today, there is no Clovis-associated DNA found in modern South Americans, the researchers said. This suggests that a continentwide population replacement happened at that time, said study co-senior researcher David Reich, a professor of genetics at Harvard Medical School and a Howard Hughes Medical Institute investigator. Following this mysterious disappearance, there is a surprising amount of genetic continuity between people who lived 9,000 years ago and those living today in multiple South American regions, the researchers said.

Although these findings shed light on early Americans, it's far from complete. The researchers acknowledge that they don't have human remains that are older than about 11,000 years old, "and thus we could not directly probe the initial movements of people into Central and South America," they wrote in the study. Moreover, although the study looked at 49 people who lived between about 11,000 and 3,000 years ago, the research would be more comprehensive if more ancient individuals from different regions were included, the researchers said.

"We lacked ancient data from Amazonia, northern South America and the Caribbean, and thus cannot determine how individuals in these regions relate to the ones we analyzed," Reich said in the statement. "Filling in these gaps should be a priority for future work."

Pacific Basin Human Geography migrations

California-Peruvian Connection

The 2018 Cell study also revealed an unexpected connection between ancient people living in California's Channel Islands and the southern Peruvian Andes at least 4,200 years ago. It appears that these two geographically distant groups have a shared ancestry, the researchers found. [Source: Laura Geggel, Live Science, November 9, 2018]

Laura Geggel wrote in Live Science: It's unlikely that people living in the Channel Islands actually traveled south to Peru, the researchers said. Rather, it's possible that these groups' ancestors sallied forth thousands of years earlier, with some ending up in the Channel Islands and others in South America. But those genes didn't become common in Peru until much later, around 4,200 years ago, when the population may have exploded, the researchers said.

"It could be that this ancestry arrived in South America thousands of years before and we simply don't have earlier individuals showing it," study co-lead researcher Nathan Nakatsuka, a research assistant in the Reich lab at Harvard Medical School, said in the statement. "There is archaeological evidence that the population in the Central Andes area greatly expanded after around 5,000 years ago. Spreads of particular subgroups during these events may be why we detect this ancestry afterward."

First Americans from Australia?

Inhabitants of what is now Australia travelled by canoe to settle in the Americans more than 30,000 years ago, some anthropologists have argues. Reuters reported: in 2004 They would have island hopped via Japan and Polynesia to the Pacific coast of the Americas at a time when sea levels were lower than they are today, Dr Silvia Gonzalez from John Moores University in Liverpool said annual meeting of the British Association for the Advancement of Science in Exeter in 2004. The claim will be unwelcome to today's native Americans who came overland from Siberia and say they were there first. Most researchers say they came across the Bering Straits from Russia to Alaska at the end of the Ice Age, up to 15,000 years ago. [Source: Reuters, September 7, 2004]

But Gonzalez said skeletal evidence pointed strongly to Australian origins and hinted that recovered DNA would corroborate it. "This is very contentious," said Gonzalez. "[Native Americans] cannot claim to have been the first people there." She said there was very strong evidence that the first migration came from Australia to the Pacific coast of America. Skulls of a people with distinctively long and narrow heads discovered in Mexico and California predated by several thousand years the more rounded features of the skulls of native Americans.

One particularly well preserved skull of a long-face woman had been carbon dated to 12,700 years ago, whereas the oldest accurately dated native American skull was only about 9000 years old. She said there were tales from Spanish missionaries of an isolated coastal community of long-face people in Baja California, known as the Pericues, who were of a completely different race and rituals from other communities in America at the time. "They appear more similar to southern Asians and the populations of the Pacific Rim than they do to northern Asians," she said. "You cannot have two face shapes coming from the same place." The last survivors were wiped out by diseases imported by the Spanish conquerors, Gonzalez said.

Researchers have ruled out the theory that the first Americans were Pacific Islanders who boated across the open ocean, because people didn't migrate to Polynesia until around 3,000 years ago and genetic evidence shows that the first Americans are only very distantly related to Polynesians. [Source: Laura Geggel, Live Science, October 9, 2023]

Those That Argue That DNA Doesn’t Tell the Whole Story

Fen Montaigne wrote in Smithsonian magazine: “Some archaeologists, like Ben A. Potter at the University of Alaska Fairbanks, emphasize that genetics can only provide a road map for new digs, not solid evidence of the Beringian Standstill theory or the settlement of the Americas 20,000 years ago. “Until there’s actual evidence that people were in fact there, then it remains just an interesting hypothesis,” he says. “All that is required is that [ancestral Native Americans] were genetically isolated from wherever the East Asians happened to be around that time. There’s absolutely nothing in the genetics that necessitates the Standstill had to be in Beringia. We don’t have evidence that people were in Beringia and Alaska then. But we do have evidence that they were around Lake Baikal and into the Russian Far East.” [Source: Fen Montaigne, Smithsonian magazine, January-February 2020]

“After Potter unearthed the 11,500-year-old remains of two infants and a girl at the Upward Sun River site in Alaska’s Tanana Valley — among the oldest human remains found in North America — Willerslev sequenced the infants’ DNA. The two scientists were co-authors on a Nature paper that “support[ed] a long-term genetic structure in ancestral Native Americans, consistent with the Beringian ‘standstill model.’”

“But Potter thinks that news stories on these and other findings have been too definitive. “One of the problems with the media coverage is its focus on a single hypothesis — a pre-16,000-year-old migration along the northwest coast — that is not well supported with evidence.” Potter remains doubtful that humans could have survived in most of Beringia during the bitter peak of the ice age, about 25,000 years ago. “Across the board,” he says, “from Europe all the way to the Bering Strait, this far north area is depopulated. There’s nobody there, and that lasts for a long time.”

Image Sources: Wikimedia Commons

Text Sources: National Geographic, New York Times, Washington Post, Los Angeles Times, Smithsonian magazine, Nature, Scientific American. Live Science, Discover magazine, Discovery News, Ancient Foods ancientfoods.wordpress.com ; Times of London, Natural History magazine, Archaeology magazine, The New Yorker, Time, Newsweek, BBC, The Guardian, Reuters, AP, AFP and other publications.

Last updated June 2024