Tag Archives: interbreeding

Neanderthal and Early Human Interbreeding Across Wide Regions: What the Evidence Shows

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Artist’s Impression of Neanderthal Life

Christian Jegou/Science Photo Library

Homo sapiens and Neanderthals likely interbred across a vast region, extending from Western Europe to Asia.

Modern humans (Homo sapiens) and Neanderthals (Homo neanderthalensis) exhibited mixed ancestry, with most non-Africans today possessing Neanderthal DNA, approximating 2% of their genome. Neanderthals also engaged in interbreeding, leading to a lineage shift in the Y chromosome influenced by Homo sapiens.

Despite increasing knowledge about the timing of this hybridization, the specific regions and scales of these interactions long remained a mystery. Ancestors of Neanderthals departed Africa around 600,000 years ago, migrating toward Europe and Western Asia. The first evidence of Homo sapiens moving from Africa includes skeletal remains from sites in modern-day Israel and Greece, dating to approximately 200,000 years ago.

Evidence suggests that Homo sapiens contributed genetically to the Neanderthal population in the Altai Mountains around 100,000 years ago. However, the primary wave of migration from Africa occurred over 60,000 years ago. Recent studies utilizing ancient genomic data indicate that significant gene flow between Homo sapiens and Neanderthals began around 50,000 years ago, with findings documented in studies of 4000 and 7000 gene transfers.

This interaction is thought to have primarily taken place in the eastern Mediterranean, although pinpointing the exact locations remains challenging.

To investigate, Matthias Karat and his team from the University of Geneva analyzed 4,147 ancient genetic samples from over 1,200 locations, with the oldest dating back approximately 44,000 years. They studied the frequency of genetic mutations (introgression alleles) originating from Neanderthal DNA that were passed down through hybridization.

“Our objective was to use Neanderthal DNA integration patterns in ancient human genomes to determine the sites of hybridization,” Carlat explains.

Findings revealed that the proportion of transferred DNA increased gradually as one moved away from the eastern Mediterranean region, plateauing approximately 3,900 kilometers westward into Europe and eastward into Asia.

“We were surprised to identify a distinct pattern of increasing introgression rates in the human genome, likely linked to human expansion from Africa,” Carlat notes. “This increase toward Europe and East Asia allows us to estimate the parameters of this hybrid zone.”

Computer simulations showed a hybrid zone potentially spanning much of Europe and the eastern Mediterranean, extending into western Asia.

Interbreeding Zone between Neanderthals and Homo sapiens

Lionel N. Di Santo et al. 2026

“Our findings suggest a continuous series of interbreeding events across both space and time,” notes Carlat. “However, the specifics of mating occurrences in this hybrid zone remain unknown.”

This hybrid zone encompasses nearly all known Neanderthal remains found across Western Eurasia, with the exception of the Altai region.

“The extensive geographical breadth of the putative hybrid zone suggests widespread interactions among populations,” states Leonard Yasi from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.

Notably, the Atlantic periphery—including western France and much of the Iberian Peninsula—was not part of the hybrid zone, despite the established presence of Neanderthals in these regions. Currat suggests that interbreeding may not have occurred here or may not be reflected in the analyzed genetic samples.

“This study reveals ongoing interactions between modern humans and Neanderthals over extensive geographical areas and extended periods,” adds Yasi. The hybrid zone may extend further, though limited ancient DNA sampling in regions like the Arabian Peninsula complicates assessment of its reach.

“This pivotal research challenges the notion that interbreeding occurred only in one area of West Asia with a singular Neanderthal population (not represented in existing genetic samples). Homo sapiens appear to have dispersed from Africa in increasing numbers across expanding territories, likely outcompeting smaller Neanderthal groups they encountered throughout most of the recognized Neanderthal range,” comments Chris Stringer from the Natural History Museum in London.

Topics:

  • Neanderthal Man/
  • Ancient Humans

Source: www.newscientist.com

Paleontologists Uncover Early Signs of Human-Maternal Interbreeding

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Paleontologists at the National Museum d’Historel in Tel Aviv University and Delige University, France, have reported a fascinating discovery involving a combination of Neanderthal and Homo sapiens skeletal features in a 5-year-old child found in 1931 at Skhūl Cave, located on Mount Carmel, Israel.

A group of Neanderthals in a cave. Image credit: Tyler B. Tretsven.

Mugarat Es Skhūl (Skhūl Cave) was uncovered in 1928 by Theodore McConne and Dorothy Garrod on Mount Carmel, Israel.

The excavation revealed skeletal remains of seven adults and three children, alongside isolated bones linked to 16 additional individuals associated with the Fauna and Musteria tool industry.

The fossils belong to Homo sapiens, or “anatomically modern humans,” dating back approximately 140,000 years to the end of the Mid Pleistocene.

The initial discoveries in the cave were of children aged three to five years.

A recent study led by Professor Israel Hirschkowitz of Tel Aviv University indicates that the child’s skull resembles the overall shape of Homo sapiens, particularly in the skull vault, with inner ear structures characteristic of the intracranial blood supply system and features of the mandible akin to Neanderthals.

“This finding highlights the earliest known human fossils exhibiting morphological traits from both of these groups,” he stated.

“This study indicates that the skeleton of the five-year-old child is a result of ongoing genetic intermingling with the local Neanderthal and Homo sapiens populations,” he added.

“Genetic research over the last decade has demonstrated that these two groups exchanged genes,” remarked Professor Hirschkowitz.

“Even today, 40,000 years after the last Neanderthals vanished, 2-6% of our genomes can be traced back to Neanderthals,” he continued.

“However, these gene exchanges occurred much later, between 60,000-40,000 years ago. In this case, we are addressing human fossils from 140,000 years ago.”

Traditionally, Neanderthals were thought to have evolved in Europe and migrated to Israeli territories approximately 70,000 years ago due to advancing glaciers.

A 2021 study revealed that early Neanderthals inhabited Israeli lands around 400,000 years ago.

This type of human is referred to as “Nescher Ramra.” Homo might have interbred with Homo sapiens, a group that began migrating out of Africa around 200,000 years ago – and according to findings from the current study, they did breed.

The children from Skhūl Cave represent the earliest fossil evidence of the social and biological bonds formed between these two groups over thousands of years.

Ultimately, local Neanderthals dwindled as they were absorbed into the Homo sapiens population, similar to Neanderthals in later Europe.

“The fossils we researched are the earliest known tangible proof of mating between Neanderthals and Homo sapiens,” Professor Hirschkowitz commented.

“In 1998, child skeletons were unearthed in Portugal, displaying features from both human groups.”

“However, that skeleton, known as the ‘Lapedo Valley Child,’ dates back just 28,000 years.”

Historically, anthropologists have attributed the fossils found in Skhūl Cave, alongside those from the Caffze cave near Nazareth, to early groups of Homo sapiens.

“Current research reveals that some fossils from the Skhūl cave are indeed the product of continuous genetic intermingling with local and ancient Neanderthal populations of Homo sapiens,” he concluded.

Survey results were published in the journal on June 14th, l’anthropologie.

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Bastien Bouvier et al. 2025. New analysis of Skhūl child’s neurological and mandible: taxonomic conclusions and cultural implications. l’anthropologie 129(3): 103385; doi: 10.1016/j.anthro.2025.103385

Source: www.sci.news

Revising the Timeline of Interbreeding Between Neanderthals and Ancient Humans

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overview

  • Many people carry small pieces of Neanderthal DNA, evidence of interbreeding between Neanderthals and ancient human ancestors.
  • Two new studies suggest that interbreeding occurred during the limited period when ancient humans left Africa.
  • Clarifying that timeline narrows the range of possible times for humans to spread to new continents.

The genetic code of many people hides mysteries that have long intrigued scientists. It’s a tiny piece of Neanderthal DNA that persists tens of thousands of years after the species disappears.

Most people outside Africa can attribute about 1% to 2% of their DNA to Neanderthal ancestry.

However, the details of its evolutionary history remain unclear. How often did ancient humans and Neanderthals interbreed? When exactly did it happen? Why did Neanderthals become extinct and why did modern humans survive? That Neanderthal DNA What is it bringing us now?

Two research groups independently analyzed collections of ancient genomes and reached the same conclusions about some of their core questions. published research Published in Nature magazine and thursday science Evidence suggests that ancient humans and Neanderthals interbred for a limited period of time as humans left Africa and migrated to new continents.

The results suggest that a wave of interbreeding occurred approximately 43,500 to 50,500 years ago. Then, over the next 100 generations, most, but not all, of the Neanderthal DNA was culled. The remaining DNA is now associated with traits such as skin pigmentation, immune response, and metabolism.

New findings suggest that this interbreeding event occurred more recently than previous estimates suggested, shifting and narrowing the window during which humans may have spread to places like modern-day China and Australia. That’s what it means.

The importance of fossilized human remains dating back more than 50,000 years, discovered in Europe and other parts of the world, has also been revealed. According to a new study, those populations became extinct and reached an evolutionary dead end.

“Human history is not just a success story. In fact, humans went extinct several times,” said Johannes Krause, author of the Nature paper and professor at Germany’s Max Planck Institute for Evolutionary Anthropology. “There are multiple lineages that we’re identifying now that didn’t affect later people.”

The discovery also shows how adept anthropologists are at reconstructing ancient DNA and analyzing it to infer the course of human history.

Priya Muajani, author of the Science paper and assistant professor of molecular and cellular biology at the University of California, said: “We can look at past events and actually reconstruct what the path we are on will be. It’s a great thing to be able to do.” Berkeley. “Although 50,000 years ago is a long time ago, having genetic data available from these samples really helps paint a more detailed picture.

The two research groups took different approaches to the study.

Moorjani’s group cataloged genomic information from 59 ancient and 275 modern humans who lived between 2,000 and 45,000 years ago. The researchers then analyzed how the distribution and length of Neanderthal DNA in those genomes changed over time.

They determined that the influx of Neanderthal genes into humans occurred about 47,000 years ago and lasted less than 7,000 years. These findings are consistent with archaeological evidence suggesting that Neanderthals and humans overlapped geographically when humans left Africa. Many scientists suspect that the two species crossed paths in the Middle East, but this has not been confirmed.

After interbreeding, natural selection retained some Neanderthal traits and discarded many more.

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Source: www.nbcnews.com

Study finds evidence of multiple instances of Denisovan populations interbreeding with modern humans

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The identification of a new human group called the Denisovans has been one of the most exciting discoveries in human evolution over the past decade. Unlike Neanderthal remains, the Denisovan fossil record consists of only a few skeletal fragments. Several Denisovan populations, which likely had vast geographic ranges, adapted to different environments and through multiple different interbreeding events that helped shape early human history, according to a new study. I passed on some of my genes.

Portrait of a young Denisovan woman based on a skeletal profile reconstructed from ancient DNA methylation maps. Image credit: Maayan Harel.

Denisovans are an extinct hominin group first identified through genome sequences determined from finger bone fragments found in the Denisova Cave in the Altai Mountains of southern Siberia.

“This was one of the most exciting discoveries in human evolution in the past decade,” said Dr Linda Ongaro, a researcher at Trinity College Dublin.

Subsequent genome analysis showed that Denisovans diverged from Neanderthals 400,000 years ago, and that at least two distinct Denisovan populations intermingled with the ancestors of modern Asians.

The only physical remains of Denisovans discovered so far are a finger bone fragment, three teeth, and a skull fragment from the Denisovan Cave. Jaw bones and rib bones from Baisiya Karst Cave on the northeastern edge of the Tibetan Plateau.

“It's a common misconception that humans evolved suddenly and cleanly from one common ancestor, but the more we learn, the more we realize that interbreeding with different hominins occurred and helped shape the humans we know today. ” said Dr. Ongaro.

“Unlike Neanderthal remains, the Denisovan fossil record consists only of finger bones, jaw bones, teeth, and skull fragments.”

“However, by exploiting the remaining Denisovan parts of modern humans' genomes, scientists have found evidence of at least three past events in which genes from different Denisovan populations invaded modern humans' genetic characteristics. I discovered.”

Each of these shows different levels of relatedness to the sequenced Altai Denisovans, illustrating the complex relationships between these sister lineages.

Dr. Ongaro and his colleague Professor Emilia Huerta Sánchez of Trinity College Dublin and Brown University, in their new paper, have a wide geographical range, from Siberia to Southeast Asia, and from Oceania to the south. We have reviewed evidence pointing to several likely Denisovan populations. America has adapted to a unique environment.

They also outlined a number of genes of Denisovan origin that conferred advantages to modern humans in different environments.

“Among these are genetic loci that confer tolerance to hypoxia or hypoxic conditions, which makes a lot of sense because we see it in the Tibetan population. Multiple genes that increase immunity. Another “Influences lipid metabolism and provides heat when stimulated by cold, providing benefits to Arctic Inuit populations,” Dr. Ongaro said.

“There are many directions for future research that will help us more fully understand how Denisovans influenced modern humans, including uncovering currently hidden traces of Denisovan ancestry. This includes more detailed genetic analyzes in understudied populations that have the potential to

“Additionally, by integrating more genetic data with archaeological information, finding more Denisovan fossils will certainly fill in some more gaps.”

of paper Published in a magazine natural genetics.

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L. Ongaro & E. Huerta-Sánchez. History of multiple Denisovan introgressions in modern humans. Nat Genetpublished on November 5, 2024. doi: 10.1038/s41588-024-01960-y

Source: www.sci.news