Contrary to the notion of confidently spreading beyond Africa, recent research shows that early modern humans repeatedly faced extinction before eventually colonizing the globe.
The latest DNA studies have similarly illuminated the contribution of our Neanderthal relatives to our achievements.
Although earlier Europeans were often considered a species that our ancestors triumphed over following their departure from Africa, recent research indicates that only those humans who interbred with Neanderthals managed to flourish, whereas other genetic lines eventually became extinct.
Actually, Neanderthal genes might have played a key role in our survival by shielding us from illnesses we had not previously faced.
For the first time, this study identifies a brief interval around 48,000 years ago when Homo sapiens interbred with Neanderthals following their departure from Africa. Afterward, these humans continued to spread across the broader globe.
Homo sapiens had previously migrated out of Africa, yet according to recent findings, those earlier populations that didn’t undergo interbreeding did not persist.
Professor Johannes Krause from the Max Planck Institute for Evolutionary Anthropology in Germany informed News that the historical narrative of contemporary humans must now be revised.
He stated that we view contemporary humans as a grand tale of triumph, emerging from Africa around 60,000 years ago and spreading across every ecosystem to dominate as the most successful mammals globally. However, initially, this was not the case; our species faced extinction numerous times during those early stages.
For many years, understanding how the sole remaining human species developed primarily involved examining the forms of our forebears’ fossilized remains from hundreds of thousands of years ago and noting the subtle shifts in their body structures over time.
The ancient remains have been sparse and often damaged. But the ability to extract and read the genetic code from bones that are many thousands of years old has lifted a veil on our mysterious past.
The DNA from the fossils reveals the narrative of these individuals, showing their relationships with one another as well as their migratory behaviors.
Despite our successful interbreeding with Neanderthals, the European population still faced some challenges.
The initial modern humans who interbred with Neanderthals and coexisted with them went extinct entirely in Europe around 40,000 years ago. However, they managed to disperse farther across the globe prior to this event.
These early global trailblazers’ forebears were ultimately the ones who went back to Europe to settle it.
The study offers fresh insights into the reasons behind the rapid disappearance of Neanderthals following the arrival of modern humans from Africa. While the exact cause remains unknown, the latest findings steer researchers away from hypotheses suggesting that our ancestors either outcompeted them through hunting or surpassed them due to physical or cognitive advantages.
Prof Krause suggests that this finding reinforces the idea that the cause was likely environmental factors.
He stated that both humans and Neanderthals disappear from Europe during this period. If our species, despite being so successful, vanished from the area, it’s not surprising that Neanderthals, with their much smaller population, also became extinct.
The climate was extremely unpredictable back then. It had the capability to shift from temperatures almost like those we experience now to conditions that were intensely frigid, often even during the span of an individual’s life, stated Prof Chris Stringer from the Natural History Museum in London, who isn’t affiliated with the recent study.
The research indicates that towards the latter part of their existence on Earth, Neanderthals had dwindled in number and exhibited lower genetic diversity compared to the contemporary modern humans with whom they coexisted. It suggests that their demise might have been precipitated by relatively minor factors, according to him.
A distinct DNA study published in the journal Science reveals that contemporary humans retained certain crucial genetic characteristics inherited from Neanderthals, which might have provided them with an evolutionary edge.
One aspect pertains to their immune system. As humans migrated out of Africa, they faced numerous diseases they had not previously encountered, making them highly vulnerable. However, interbreeding with Neanderthals provided their descendants with enhanced resistance against these illnesses.
Getting Neanderthal DNA might have contributed to our success as it provided enhanced adaptability beyond Africa,” explained Prof Stringer. “Our species evolved in Africa, while the Neanderthals developed their traits outside of Africa.
Through interbreeding with the Neanderthals, we received an immediate boost to our immune systems.
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