Mitogenome evidence shows two radiation events and dispersals of matrilineal ancestry from northern coastal China to the Americas and Japan: EurekaAlert!
In what would embarrass creationists if their cult beliefs were based on real-world evidence, a team of geneticists has shown that there were two waves of migration from the northern coastal region of China into North America, tens of thousands of years before creationists believe the entire human population of Earth was reduced to just eight individuals in a genocidal flood. The team, led by Yu-Chun Li, together with colleagues at the Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China and the Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, Pavia, Italy, published their findings yesterday, in an open access paper in Cell Reports.
In normal, intellectually honest people, with the humility to allow their opinions to be led by the evidence, having a basic belief refuted would be a reason to change their mind; for a creationist however, it's a reason to find a strategy for dismissing the evidence and retaining a counter-factual belief, because the mere thought of being wrong is an existential threat to a creationist.
To arrive at their conclusions, the researchers analysed mitochondrial DNA (mtDNA) in thousands of ancient samples:
Mitochondrial DNAIn information made available in UrekaAlert!, Cell Press gave the following details:
Mitochondrial DNA (mtDNA) is a small, circular DNA molecule found within the mitochondria, which are organelles responsible for energy production in cells. Unlike nuclear DNA, which is inherited from both parents, mtDNA is passed down exclusively from the mother to her offspring. This unique inheritance pattern makes mtDNA particularly useful for studying human ancestry and tracing maternal lineages. One key characteristic of mtDNA is its high mutation rate. These mutations occur at a relatively steady rate, allowing scientists to analyze the sequence variations in mtDNA and construct an evolutionary tree known as a phylogenetic tree or haplogroup tree. Haplogroups are defined as groups of individuals who share a common ancestor, as determined by specific mtDNA sequence markers. By analyzing mtDNA sequences from diverse populations around the world, scientists have identified several major haplogroups that represent different branches on the human family tree. These haplogroups are labeled with letters (such as H, L, N, etc.) and further divided into subclades with more specific mutations. Each haplogroup and subclade corresponds to a specific geographic origin and migration path, providing insights into the ancient human populations and their movements. For example, the macrohaplogroup L is prevalent in sub-Saharan Africa and is believed to have originated there. From Africa, humans migrated to different parts of the world, leading to the emergence of other haplogroups in different regions. Haplogroup H is the most common haplogroup in Europe and is thought to have originated in the Near East before spreading into Europe. Haplogroup M and its subclades are predominant in Asia, while haplogroup N is found in Siberia and Native American populations. One of the most famous applications of mtDNA in tracing human groups is the study of the African diaspora and the origins of modern humans. By examining mtDNA from individuals of African descent worldwide, scientists have been able to reconstruct ancestral lineages and shed light on the migration patterns of early humans. This research has contributed to our understanding of human evolution and the peopling of different regions. To explore this topic further and access specific references, I recommend referring to scientific publications and research articles on mitochondrial DNA and human population genetics. Some notable studies include:
- Behar, D.M., van Oven, M., Rosset, S., et al. (2012). A "Copernican" reassessment of the human mitochondrial DNA tree from its root. American Journal of Human Genetics, 90(4), 675-684.
- Soares, P., Alshamali, F., Pereira, J.B., et al. (2012). The Expansion of mtDNA Haplogroup L3 within and out of Africa. Molecular Biology and Evolution, 29(3), 915-927.
- Pereira, L., Freitas, F., Fernandes, V., et al. (2009). The diversity present in 5140 human mitochondrial genomes. American Journal of Human Genetics, 84(5), 628-640.
ChatGPT3 "Tell me all about mitochondrial DNA and its role in tracing human groups, with reference, please." [Response to user question] Retrieved from https://chat.openai.com/
Scientists have used mitochondrial DNA to trace a female lineage from northern coastal China to the Americas. By integrating contemporary and ancient mitochondrial DNA, the team found evidence of at least two migrations: one during the last ice age, and one during the subsequent melting period. Around the same time as the second migration, another branch of the same lineage migrated to Japan, which could explain Paleolithic archeological similarities between the Americas, China, and Japan. The study appears May 9 in the journal Cell Reports.The team give more details in the abstract to their paper:
Though it was long assumed that Native Americans descended from Siberians who crossed over the Bering Strait’s ephemeral land bridge, more recent genetic, geological, and archeological evidence suggests that multiple waves of humans journeyed to the Americas from various parts of Eurasia.The Asian ancestry of Native Americans is more complicated than previously indicated. In addition to previously described ancestral sources in Siberia, Australo-Melanesia, and Southeast Asia, we show that northern coastal China also contributed to the gene pool of Native Americans.
We were surprised to find that this ancestral source also contributed to the Japanese gene pool, especially the indigenous Ainus.
Yu-Chun Li, First author
Molecular anthropologist
Kunming Institute of Zoology
Chinese Academy of Sciences
Kunming, Yunnan, China
To shed light on the history of Native Americans in Asia, a team of researchers from the Chinese Academy of Sciences followed the trail of an ancestral lineage that might link East Asian Paleolithic-age populations to founding populations in Chile, Peru, Bolivia, Brazil, Ecuador, Mexico, and California. The lineage in question is present in mitochondrial DNA, which can be used to trace kinship through the female line.
The researchers scoured over 100,000 contemporary and 15,000 ancient DNA samples from across Eurasia to eventually identify 216 contemporary and 39 ancient individuals belonging to the rare lineage. By comparing the accumulated mutations, geographic locations, and carbon-dated age of each of these individuals, the researchers were able to trace the lineage’s branching path. They identified two migration events from northern coastal China to the Americas, and in both cases, they think that the travelers probably set dock in America via the Pacific coast rather than by crossing the inland ice-free corridor (which would not have opened at the time).
The first radiation event occurred between 19,500 and 26,000 years ago during the Last Glacial Maximum, when ice sheet coverage was at its greatest and conditions in northern China were likely inhospitable for humans. The second radiation occurred during the subsequent deglaciation or melting period, between 19,000 and 11,500 years ago. There was a rapid increase in human populations at this time, probably due to the improved climate, which may have fueled expansion into other geographical regions.
The researchers also uncovered an unexpected genetic link between Native Americans and Japanese people. During the deglaciation period, another group branched out from northern coastal China and traveled to Japan.[Archaeological similarities] suggests that the Pleistocene connection among the Americas, China, and Japan was not confined to culture but also to genetics.
The origins of several founder groups are still elusive or controversial. Next, we plan to collect and investigate more Eurasian lineages to obtain a more complete picture on the origin of Native Americans.
Qing-Peng Kong, senior author
Evolutionary geneticist
Kunming Institute of Zoology
Chinese Academy of Sciences
Kunming, Yunnan, China.
This discovery helps to explain archeological similarities between the Paleolithic peoples of China, Japan, and the Americas. Specifically, the three regions share similarities in how they crafted stemmed projectile points for arrowheads and spears.
Though the study focused on mitochondrial DNA, complementary evidence from Y chromosomal DNA suggests that male ancestors of Native Americans also lived in northern China at around the same time as these female ancestors.
This study adds another piece to the puzzle that is Native American ancestry, but many other elements remain unclear.
HighlightsProperly understood, mtDNA refutes almost all creationism's basic dogmas. The known mutation rate shows that the present diversity would not have been reached if the biblical flood was a real event. It also shows a continuous history of lineages extending way back beyond the date of that legendary flood and way back past the date creationists insist the Universe was created. It also shows that the whole of humanity could not possibly be descended from a single founder female, whether involving incestuous relationships, or not. There are simply too many known lineages for that.
- The Native American lineage D4h3a can trace its ancestry to northern coastal China
- Radiations of D4h contribute to gene pools of Native Americans and Japanese
- Coastal radiations of D4h support the coastal route of early Native Americans
Summary
Although it is widely recognized that the ancestors of Native Americans (NAs) primarily came from Siberia, the link between mitochondrial DNA (mtDNA) lineage D4h3a (typical of NAs) and D4h3b (found so far only in East China and Thailand) raises the possibility that the ancestral sources for early NAs were more variegated than hypothesized. Here, we analyze 216 contemporary (including 106 newly sequenced) D4h mitogenomes and 39 previously reported ancient D4h data. The results reveal two radiation events of D4h in northern coastal China, one during the Last Glacial Maximum and the other within the last deglaciation, which facilitated the dispersals of D4h sub-branches to different areas including the Americas and the Japanese archipelago. The coastal distributions of the NA (D4h3a) and Japanese lineages (D4h1a and D4h2), in combination with the Paleolithic archaeological similarities among Northern China, the Americas, and Japan, lend support to the coastal dispersal scenario of early NAs.
Li, Yu-Chun; Gao, Zong-Liang; Liu, Kai-Jun; Tian, Jiao-Yang; Yang, Bin-Yu; Rahman, Zia Ur; Yang, Li-Qin; Zhang, Su-Hua; Li, Cheng-Tao; Achilli, Alessandro; Semino, Ornella; Torroni, Antonio; Kong, Qing-Peng
Mitogenome evidence shows two radiation events and dispersals of matrilineal ancestry from northern coastal China to the Americas and Japan
Cell Reports, 112413. DOI: 10.1016/j.celrep.2023.112413
Copyright: © 2023 The authors.
Published by Elsevier Inc Open access.
Reprinted under a Creative Commons Attribution – Noncommercial – NoDerivs licence (CC BY-NC-ND 4.0)
In conjunction with the male Y chromosome, which traces the male line, mtDNA shows that the hypothetical mitochondrial Eve and the hypothetical Y-chromosome Adam could never have met and interbred. In fact, they may not even have been Homo sapiens, but some remote ancestor belonging to an ancestral species. After all, your genes have spent much longer in pre-hominin, and even pre-mammalian species than they have spent in H. sapiens.
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