Neanderthals and modern humans separated as species at least 800,000 years ago – more than twice as long ago as was previously thought
- Researchers analysed dental evolutionary rates across different hominin species
- Teeth of hominins in Spain diverged from modern humans earlier than thought
- They studied the Sima de los Huesos icave site in Spain’s Atapuerca Mountains
- Previous studies date it to around 430,000 years ago in the Middle Pleistocene
Neanderthals and modern humans split from their common ancestor at least 800,000 years ago, more than twice as long ago as was previously thought.
Most DNA-based estimates suggest that this took place between 300 and 500,000 years ago.
Researchers from University College London analysed dental evolutionary rates across different hominin species, focusing on early Neanderthals.
This revealed that that the teeth of hominins from Sima de los Huesos om Spain – ancestors of the Neanderthals – diverged from the modern human lineage earlier than previously assumed.
Neanderthals and modern humans split from their common ancestor at least 800,000 years ago, more than twice as long ago as was previously thought. Researchers analysed dental evolutionary rates (pictured) across different hominin species to make the finding
Sima de los Huesos is a cave site in Atapuerca Mountains where archaeologists have recovered fossils of almost 30 people.
Previous studies date the site to around 430,000 years ago in the Middle Pleistocene.
This makes it one of the oldest and largest collections of human remains discovered to date.
Dr Aida Gomez-Robles, of UCL’s anthropology department, said: ‘Any divergence time between Neanderthals and modern humans younger than 800,000 years ago would have entailed an unexpectedly fast dental evolution in the early Neanderthals from Sima de los Huesos.
‘There are different factors that could potentially explain these results, including strong selection to change the teeth of these hominins or their isolation from other Neanderthals found in mainland Europe.
‘However, the simplest explanation is that the divergence between Neanderthals and modern humans was older than 800,000 years. This would make the evolutionary rates of the early Neanderthals from Sima de los Huesos roughly comparable to those found in other species.’
The study revealed that that the teeth of hominins (pictured) from Sima de los Huesos in Spain – ancestors of the Neanderthals – diverged from the modern human lineage earlier than previously assumed
WHO WERE THE NEANDERTHALS?
The Neanderthals were a close human ancestor that mysteriously died out around 50,000 years ago.
The species lived in Africa with early humans for hundreds of millennia before moving across to Europe around 500,000 years ago.
They were later joined by humans taking the same journey some time in the past 100,000 years.
The Neanderthals were a cousin species of humans but not a direct ancestor – the two species split from a common ancestor – that perished around 50,000 years ago. Pictured is a Neanderthal museum exhibit
These were the original ‘cavemen’, historically thought to be dim-witted and brutish compared to modern humans.
In recent years though, and especially over the last decade, it has become increasingly apparent we’ve been selling Neanderthals short.
A growing body of evidence points to a more sophisticated and multi-talented kind of ‘caveman’ than anyone thought possible.
It now seems likely that Neanderthals buried their dead with the concept of an afterlife in mind.
Additionally, their diets and behaviour were surprisingly flexible.
They used body art such as pigments and beads, and they were the very first artists, with Neanderthal cave art (and symbolism) in Spain apparently predating the earliest modern human art by some 20,000 years.
Modern humans share a common ancestor with Neanderthals, the extinct species that were our closest prehistoric relatives.
However, the details on when and how they diverged are a matter of intense debate within the anthropological community.
Ancient DNA analyses have generally indicated that both lineages diverged around 300,000 to 500,000 years ago, which has strongly influenced the interpretation of the hominin fossil record.
This divergence time, however, is not compatible with the anatomical and genetic Neanderthal similarities observed in the hominins from Sima de los Huesos.
The Sima fossils are considered likely Neanderthal ancestors based on both anatomical features and DNA analysis.
Dr Gomez-Robles said: ‘Sima de los Huesos hominins are characterised by very small posterior teeth (premolars and molars) that show multiple similarities with classic Neanderthals.
‘It is likely that the small and Neanderthal-looking teeth of these hominins evolved from the larger and more primitive teeth present in the last common ancestor of Neanderthals and modern humans.’
Dental shape has evolved at very similar rates across all hominin species, including those with very expanded and very reduced teeth.
This new study examined the time at which Neanderthals and modern humans should have diverged to make the evolutionary rate of the early Neanderthals from Sima de los Huesos similar to those observed in other hominins.
The research used quantitative data to measure the evolution of dental shape across hominin species assuming different divergent times between Neanderthals and modern humans, and accounting for the uncertainty about the evolutionary relationships between different hominin species.
The Sima people’s teeth are very different from those that we would expect to find in their last common ancestral species with modern humans, suggesting that they evolved separately over a long period of time to develop such stark differences.
The study has significant implications for the identification of Homo sapiens last common ancestral species with Neanderthals, as it allows ruling out all the groups postdating 800,000 year ago.
The full findings of the study were published in the journal Science Advances.
WHAT KILLED OFF THE NEANDERTHALS?
The first Homo sapiens reached Europe around 43,000 years ago, replacing the Neanderthals there approximately 3,000 years later.
There are many theories as to what drove the downfall of the Neanderthals.
Experts have suggested that early humans may have carried tropical diseases with them from Africa that wiped out their ape-like cousins.
The first Homo sapiens reached Europe around 43,000 years ago, replacing the Neanderthals (model pictured) there approximately 3,000 years later
Others claim that plummeting temperatures due to climate change wiped out the Neanderthals.
The predominant theory is that early humans killed off the species through competition for food and habitat.
Homo sapiens’ superior brain power and hunting techniques meant the Neanderthals couldn’t compete.
Based on scans of Neanderthal skulls, a new theory suggests the heavy-browed hominids lacked key human brain regions vital for memory, thinking and communication skills.
That would have affected their social and cognitive abilities – and could have killed them off as they were unable to adapt to climate change.
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