Ancient human relatives the first to bury their dead thousands of years ago, study finds

Homo Naledi, a primitive human species discovered in 2015, might have buried their dead, a new study showed. The discovery is shocking because their brain was a third of the size of ours.

Burying the dead is considered advanced human conduct. In anthropology, it is called funerary behavior, which means the species understands the importance of the passing away.

The alleged burial site was found deep down in the subsystem of a cave in South Africa. According to National Geographic, the burials would be the earliest known by at least 100,000 years.

The same team discovered Homo Naledi in that same cave in 2015. Back then, the project's head scientist, Lee Berger, suggested that primitive humans dragged the bodies.

Now, they claim that Homo Naledi buried them. According to The New York Times, the team analyzed the sediments surrounding the bodies to come to that conclusion.

Some colleagues were skeptical even in 2015 when the team claimed that Homo Naledi showed mortuary behavior (and not funerary), something that chimps or elephants do.

National Geographic described the three most relevant hypotheses skeptical academics used to explain why the bodies were in the hard-to-reach subsystem.

The first one was that water dragged the bodies down to the bottom of the cave, which was then shut and dried over time. The second one was that predators had taken the bodies inside the cave.

The third hypothesis was that modern humans, which coexisted with Homo Naledi for at least 50,000 years, dragged and buried the bodies inside the cave.

The new research discarded all three hypotheses by showing no signs of water, bite marks, or later access to the cave. According to CNN, it also showed that the bodies were laid in a fetal position.

Some experts cited by CNN and National Geographic have shown less skepticism, but many maintain that other studies are still needed.

"I'm highly optimistic that they have burials, but the jury is still out," Michael Petraglia, the director of the Australian Research Center for Human Evolution, told the New York Times.

However, Andre Gonçalves, an expert in how animals interact with the dead, told National Geographic that it is unsurprising given how close we are to Homo Naledi.

"We are separated from chimps and bonobos by six million years," he told the magazine. "Three hundred thousand years is nothing."

The team also found rests that suggest that Homo Naledi light fire illuminate their way inside the cave and wall engravings in the subsystems.

Engravings are another significant cognitive evolution step for our species that scientists believe was associated with the size of our brain.

That is why many engraving experts cited by The New York Times said the evidence did not yet support these extraordinary findings about Homo naledi.

Archeologist Curtis Marean told National Geographic that researchers have found "very similar" engravings in Homo sapiens sites in the region, as well as in Gibraltar.

John Hawks of the University of Wisconsin, part of the research team, told the New York Times that many samples still need to be tested, but they published some first impressions anyway.

The purpose was to open a discussion with other researchers. "For me, it's much more important to document and to share than it is to be right," Dr. Hawks told the newspaper.