Over the millions of years that humans have evolved, our brains have tripled in size and our behavior has become exponentially more complex. Early small-brained hominins (members of the human family) made only simple stone tools. Later, our wiser ancestors invented more sophisticated tools and developed more sophisticated survival strategies. As for the complexities of our own ovocephalic behavior, sage Yes, we will do everything in our power to develop technology that will transport us to all corners of the planet, to ritually bury our dead, to form extensive social networks, and to create art, music, and art that are rich in common meaning. created a language. Scientists have long hypothesized that increased brain size drives these technological and cognitive advances. Now, a startling new discovery at a fossil site in South Africa calls into question this fundamental tenet of human evolution.
Researchers working in the Rising Star cave system near Johannesburg report finding evidence of a small-brained fossil hominin species. homoster They engaged in some sophisticated behaviors previously associated only with large-brained hominins.His three papers published in journals describe the findings e-lifethey claim H. Naledi Its brain is about one-third the size of ours, used fire as a light source, went to great lengths to bury the dead, and carved perhaps symbolic patterns into the rock walls of cave systems. rice field. The findings are preliminary, but if future research confirms them, scientists may need to rethink how we came to be human.
H. Naledi A relatively recent addition to the pantheon of known human species. In 2013 and 2014, a team led by Lee Berger, a paleoanthropologist at the University of the Witwatersrand in Johannesburg and now a National Geographic resident explorer, collected more than 1,500 fossil specimens belonging to at least 15 organisms. Recovered. People from the depths of Rising Star. Fossils have revealed humans with an unexpected mix of old and new traits. It walked perfectly upright like modern humans, and its hands were as dexterous as ours. But the shoulders were built for climbing, and the teeth were shaped like those of the early hominids of the genus. australopithecus, John Hawkes, a team member at the University of Wisconsin-Madison, explains: The most impressive of these is H. Naledi Brain size was only 450 to 600 Cubic centimeter (cc). For comparison, H. clever Average brain size is about 1,400 cc. Berger and his team announced the discovery as a scientifically new species in 2015. Two years later, they were able to date the fossil to between 236,000 and 335,000 years ago. This is surprisingly recent for a species with such a small brain. other primitive features.
Controversy is brewing H. Naledi From the beginning. The remains have been found in parts of the cave system, which are very difficult to access today and, to the best of the team’s knowledge, were just as difficult to access then. H. Naledi visited. Few medium- or large-sized animal bones are known from this site. H. Naledi I accidentally fell into a cave. And the discovery team says there is no evidence that the bones were carried by the rapids to the site. Berger and his collaborators argued that the implications were: H. Naledi This underground cave system was intentionally entered to enshrine the dead. If so, they must have used a light source—fire—to navigate the dark and dangerous tunnels, chutes, and rooms of the Rising Star. But mortuary behavior and fire control have long been considered the exclusive prerogative of larger-brained hominins. Despite no direct evidence of fire or intentional burial of bodies, H. Naledi Considering its small brain size was still firmly in the realm of speculation, it could have been surprisingly sophisticated.
Subsequent work on the cave substantially strengthened that claim. Berger and his colleagues report evidence of burials in two locations for Rising Star, the Dina Reddy room and the Hill room. H. Naledi The bodies were deliberately placed in a hole dug in the ground, after which the bodies were covered with dirt. In one case, the corpse was laid out in a fetal position within the pit, a common feature of early corpses. H. clever burial. In another burial, a rock that researchers described as resembling a stone tool was found next to the hand of one of the dead. If it is in fact stone tools or other artifacts, it is the only one found associated with humans. H. Naledi to date.
After discovering the burial ground, Berger and Hawkes set their sights on searching the Rising Star for clues to its culture. H. Naledi. And this time, Mr. Berger wanted to explore the cave system himself. Because of his large build, he could not enter the stage of Rising Star. H. Naledi I couldn’t get past the narrowest point on the route to enter the Fossil Room. He hired a team of lean scientists to conduct all the exploration and excavations that led to his first research publications. And last summer, after shedding 55 pounds, Berger finally stepped into the heart of the rising star.and then he realized Soot on the ceiling and charcoal and burnt bone fragments on the floor indicate that fire was used within the cave. At the same time, the hearth was discovered by Keneiloe Moropian, a team member from the University of the Witwatersrand who was excavating another part of the cave system known as Dragon’s Back. “These burial chambers, adjoining rooms, and even corridors are almost all spaces with fire marks,” Berger says.
Berger also made another, perhaps more surprising, discovery that day at Rising Star. It was a design carved into a cave wall. The sculpture consists of isolated lines and geometric motifs such as crosses, squares, triangles, Xs, hash marks, and ladder shapes known as scalarforms. The marks were carved deep into the dolomite rock near the burial grounds of Dinaledi and Hill’s chambers. Dolomite is a particularly hard rock, with a mineral hardness of about 4.7 on the Mohs scale, “about half that of diamond,” Berger says. That is, the sculptor would have had to expend considerable effort in putting these marks. The sculpted surface appears to have been smoothed with hammerstone and polished with dirt and sand, the researchers said. Some carved areas also glow with residue that may be the result of repeated contact with the rock.
If H. Naledi If tiny brains were used to bury the dead, use fire as a light source, and create sculptures, scientists may need to rethink the relationship between brain size and behavior. We need to take a step back and try to understand “the social and community emotional dynamics that make this kind of complex behavior possible without having a big, complex brain,” says team member Agustin of Princeton University. Fuentes says. Taking this perspective allows us to think about human evolution in new ways, he adds, adding that “we know a lot more than we think we do.” reminds me of
“This is about our perception of what it means to be human, what it means to be intelligent enough to make art, what it means to communicate graphically. It’s a challenge,” says Genevieve von Petzinger, an authority on rock art who was not involved in the new paper. . Until just 25 years before him, the conventional understanding was: clever person Invented art in Europe 35,000 years ago. Over the past two decades, researchers have found evidence that our cousins, the Neanderthals and Denisovans, also made art. homoster But their brains were much smaller than those of those hominins. Von Petzinger notes that the discovery of the rising star is preliminary, and researchers have yet to conduct detailed studies to figure out “who, where and when they made it.” there is However, “I think you have nothing to lose by being open-minded, as long as you take this as the beginning of a new and exciting conversation.”
Some experts not involved in the new study think Berger and his colleagues are ahead. Durham archaeologist Paul Pettit said: “The research team believes this was a deliberate burial, in which a shallow grave was excavated, a corpse was placed in it, and then the excavated sediment covered the corpse. “I’m not sure I’ve proven it,” he said. British university. A full excavation of the site would probably solve the problem, but the team’s “wise” decision to leave some of the deposits intact for now was “…their data has been partially investigated. , no matter how impressive they are, unfortunately they don’t present evidence,” he says. He clearly and unequivocally proves that he was deliberately buried. Pettit suggests that the washing may have been caused by seasonal, low-energy movement of water within the cave system. H. NalediIt remains in natural depressions in the ground.
Archaeologist Michael Petraglia of Australia’s Griffith University believes the researchers have produced good evidence for the burial, but he doubts the claims: H. Naledi I was in charge of printmaking. One of the big problems is that scientists have yet to establish a direct date for the traces. The discovery team claims there is no indication that other hominins exist. H. Naledi And modern spelunkers have entered the Dark Zone of the Rising Star, where fossils and archaeological material have been found, hence its design is believed to be: H. Naledi. But Petraglia has not been persuaded. “The proof is that homoster The rock carvings made are weak. The skeletal material and the carvings are in the same cave context, but there is no direct way to relate them at this time,” he says. Evidence of the fire is similarly problematic, and the researchers have not yet released a date for the material. “There is no reason to believe that at this stage.” homoster It’s a controlled fire, and we’re waiting for compelling scientific evidence to prove this to be the case,” Petraglia said.
The team is working to obtain evidence for that, and others that contain genetic material. homoster For example, a person found at the scene. And they want to involve other researchers in their efforts as they consider how best to advance the study of the cave system’s rich material. Some types of analysis rely on inherently destructive methods such as excavation. Some rely on less invasive methods such as laser scanning. “You’ve just met a species more complex than modern big-brained humans, and this was the space,” Berger says of Rising Star. “What to do with it? Destroy it? Respect it? I think we should discuss this as a community.”
