Many believed humans have bigger brains than their predecessors, enabling them to do complex tasks like burying the dead. However, a new study suggests that our distant relatives made the first burial site with smaller brains.

Homo Naledi Built World's Oldest Burial Site

The earliest known graveyard in the world, according to South African paleontologists, contains the remains of a small-brained distant ancestor of modern humans who was previously believed to be incapable of complex behavior.

Under the direction of well-known paleoanthropologist Lee Berger, scientists announced in June that they had found multiple specimens of Homo naledi, a Stone Age hominid that climbed trees, buried 30 meters (100 feet) below the surface in a cave system inside the Cradle of Humankind, a UNESCO World Heritage site close to Johannesburg.

"These are the most ancient interments yet recorded in the hominin record, earlier than evidence of Homo sapiens interments by at least 100,000 year," the researchers wrote in a series of preprint papers.

The results cast doubt on the conventional wisdom of human evolution, which holds that larger brains enabled the execution of intricate, "meaning-making" tasks like interring the dead.

"These discoveries show that mortuary practices were not limited to H. sapiens or other hominins with large brain sizes," the scientists added.

The oldest burials ever discovered were in the Middle East and Africa, and they included Homo sapiens remains that date back to 100,000 years. The ones found in South Africa belong to at least 200,000 BC, according to Berger and his colleagues, whose earlier claims have generated controversy.

Crucially, they are also members of Homo naledi, a primordial species that existed at the nexus of modern humans and apes. Standing roughly 1.5 meters (five feet) tall, Homo naledi had brains the size of oranges.

The idea that our evolutionary route was a straight line had already been upended by the species that Berger discovered, with their curled fingers and toes, tool-wielding hands, and walking feet. Researchers claim there is evidence to suggest that the holes, where at least five remains are found, were intentionally dug and subsequently filled in.

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Who Are the Homo Naledi?

On an expedition headed by Berger that started in October 2013, the Dinaledi Chamber of the Rising Star Cave system in South Africa yielded the first evidence of fossilized hominins. Over 1550 specimens from at least 15 Homo naledi individuals were found at the site between November 2013 and March 2014.

The greatest known collection of a single hominid species discovered in Africa is still from this excavation. In 2013, Steven Tucker and Rick Hunter discovered 133 more Homo naledi specimens in the neighboring Lesedi Chamber, indicating the presence of at least three more individuals-two adults and a child. The Homo naledi bones were dated in 2017 and were found to be between 335,000 and 236,000 years old.

Very little is known about the ecology and biology of Homo naledi because there aren't any other animal remains or implements connected to the species. In the end, its teeth might reveal information about the habitat and food of this species from southern Africa.

In actuality, its teeth are different from those of other Homo species that existed at the same period. Therefore, even though Homo naledi shared many other morphological characteristics with other Homo species, it's possible that they lived in different environments.

It is still unclear where Homo naledi fits into the evolutionary tree of the Homo genus. Homo naledi had a combination of characteristics found in both Homo and Australopithecus, especially in the hands, feet, and brain size, as well as in the pelvis and shoulder. More comparative studies are required to discover more about the relationships between Homo naledi and other Homo species, including Homo erectus.

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