New research is challenging what we thought we knew about our prehistoric cousins, the now extinct Neanderthals. DNA from fossils from a cave in Spain show that Neanderthals are almost twice as old as previously thought, having emerged up to 765,000 years ago. The new timelines force a dramatic rewrite of previously held beliefs of our ancient past.

Geneticists have examined a collection of fossilized bones that are the remains of a Neanderthal family from the Sima de los Huesos (“pit of bones”) cave in northern Spain. The scientists were able to sequence DNA from a prehistoric tooth and a leg bone —a remarkable technical feat—dating them to between 300,000 and 400,000 years old. The team identified one million to two million base pairs of ancient nuclear DNA. This is the oldest partial genome ever sequenced, an impressive breakthrough.

The results may “push back the date for the origins of the distinct ancestors of Neandertals and modern humans,” reports an article in journal Science of the American Association for the Advancement of Science (AAAS).

Dr. Matthias Meyer, paleogeneticist at the Max Planck Institute for Evolutionary Anthropology in Germany led the work. Meyer said that “Neanderthals, and their relatives the Denisovans, could have split from their common ancestor with modern humans up to 765,000 years ago.”

Cave excavation in Atapuerca, Spain. ( CC BY-SA 3.0 )

According to MailOnline, the findings “could lead to a dramatic shake up of the current shape of the human family tree,” as it was previously believed that Homo sapiens (modern humans) only emerged in Africa 200,000 years ago before they spread across the world. Homo neanderthalensis (Neanderthals) were believed to have evolved in Eurasia from a common ancestor. The new genome results creates an earlier timeline for both species, and thus an earlier split in the evolutionary tree.

Science journal writes, “They scanned this DNA for unique markers found only in Neandertals or Denisovans or modern humans, and found that the two Sima fossils shared far more alleles—different nucleotides at the same address in the genome—with Neandertals than Denisovans or modern humans. ‘Indeed, the Sima de los Huesos specimens are early Neandertals or related to early Neandertals,’ suggesting that the split of Denisovans and Neandertals should be moved back in time, Meyer reported at the meeting.

“That would mean that the ancestors of humans were already wandering down a solitary path apart from the other kinds of archaic humans on the planet 100,000 to 400,000 years earlier than expected.”

Skull number 5 of the Pit of Bones, as it appeared in the campaign of 1992. In later campaigns the jaw was exhumed. ( Wikimedia Commons )

Thousands of fossilized remains were found in the Sima de los Huesos (“pit of bones”) caves in the 1990s. The bones and teeth belonged to 28 individuals, and the fossils looked like primitive Neanderthals to researchers. The finds from cave site in the Sierra de Atapuerca of Burgos , Spain have revolutionized the current understanding of hominin evolution.

Models of a Neanderthal man and woman. Neanderthal Museum, Dusseldorf. ( Wikimedia Commons )

Our closest human relative, Neanderthals are not well understood, with ideas on how they lived and why they died out still just theories . For hundreds of thousands of years they lived across Europe, Eurasia, and the Middle East, it’s believed interbreeding with, and contributing to the DNA of modern humans.

DNA results from the cave site in Spain come at a time when fossil discoveries are shedding light on the history of modern humans and our prehistoric relatives. Another recent discovery has been dubbed one of the greatest fossil discoveries of the past half century, and the largest fossil hominin find in Africa, as scientists have recovered the remains what are thought to be new species of human relative in South Africa, named ‘Homo naledi’ , adding another piece to the complicated puzzle.

The so-called “Homo naledi” fossilized bones recovered from the Rising Star cave in South Africa. Credit: Lee R Berger et al./Creative Commons

The Neanderthal DNA findings by Dr. Meyer and colleagues were presented this week at the fifth annual meeting of the European Society for the study of Human Evolution .

Featured Image: Deriv; Skull of a modern human (left) and a Neanderthal (right). Museum of Natural History in Cleveland. ( Wikimedia Commons ), and a DNA molecule ( C. Bock/Wikimedia Commons )

By Liz Leafloor