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Post by Admin on Nov 5, 2021 2:25:57 GMT
It’s tiny, incomplete, and undeniably awesome. Named “Leti,” this is the first known skull belonging to a Homo naledi child—a fossil that’s shedding new light onto this mysterious group of extinct humans. The skull fragments, all 28 of them, were found in a tight passage measuring just 5.9 inches (15 cm) wide and 31.5 inches (80 cm) long. So narrow was this passage that researchers had to lie flat and perform a “superman crawl” to pull themselves through, the AFP reports. The cranial remnants and six associated teeth were resting on a limestone shelf located an arm’s reach from the cave floor. Less than 40 feet (12 meters) from this spot is the Dinaledi Chamber—the area within the Rising Star cave system where anthropologists uncovered the first traces of Homo naledi back in 2013. The cave has since yielded over 2,000 H. naledi fossils, from all stages of life, yet there’s still much to learn about this extinct group of hominins. They date back to an interesting time in human evolution—about 250,000 years ago—when modern humans shared this planet with several other Homo species, such as Neanderthals and Homo erectus. “Homo naledi remains one of the most enigmatic ancient human relatives ever discovered,” Lee Berger, an anthropologist at the University of the Witwatersrand and a co-author of one of two papers describing the new fossil, both published in PaleoAnthropology, explained in a press release. “It is clearly a primitive species, existing at a time when previously we thought only modern humans were in Africa.” Scientists aren’t sure how modern humans are related to H. naledi, but we likely share a common ancestor. It’s also not known if H. naledi ventured far beyond the Rising Star cave system, a 1.2-mile (2-kilometer) complex of passages and chambers located near Johannesburg, South Africa. These hominins may have been a small group that branched off the human family tree, or they might’ve been widespread across much of Africa. We don’t know. The discovery of the first H. naledi child skull is significant, as it could tell us new things about this species, including their rates of growth and development. Anthropologist Juliet Brophy from Louisiana State University, a co-author of both studies, said it’s important to learn about our ancestors and the rates at which they matured because it speaks to a host of anatomical and behavioral changes. Trouble is, we don’t really know a whole lot when it comes to this. “We have a rough idea,” Brophy explained. “We know the rates are not as fast as a chimpanzee and not as slow as a modern human. With the small number of non-adults in the fossil record, it is very hard to reconstruct,” she said. The rare data being collected in the Rising Star cave system—and now the partial child skull of H. naledi—could allow for the reconstruction of their various life stages. The scientists found the fossil in 2017, and they’ve named it “Leti,” which is short for Letimela—the Setswana word for “the lost one.” Cause of death could not be determined, as no signs of injury or disease were found on the skull fragments or teeth. Leti was perhaps between four and six years of age when they died, but this estimate assumes a dental growth pattern consistent with modern humans. Sex could not be determined, nor the height or weight of the child. Surprisingly, the team did not date the fossil, prompting me to ask Brophy why. “The fossil wasn’t dated because we would have to date the fossil itself and dating is destructive. We did not want to lose any of the fossils,” she replied. “We also do not have any reason to suggest that the fossils are from a radically different time than the Dinaledi or Lesedi Chamber fossils. In fact, we hypothesize that they are from a similar time frame as the nearby remains.” Immature Hominin Craniodental Remains From a New Locality in the Rising Star Cave System, South Africa Abstract Homo naledi is known from the Rising Star cave system, South Africa, where its remains have previously been reported from two localities: the Dinaledi Chamber (U.W. 101) and Lesedi Chamber (U.W. 102). Continued exploration of the cave system has expanded our knowledge of the Dinaledi Chamber and its surrounding passageways (the Dinaledi Subsystem), leading to the discovery of new fossil localities. This paper discusses the fossil assemblage from the locality designated U.W. 110. This locality is within a narrow fissure of the Dinaledi Subsystem approximately 12 meters southwest of the 2013–2014 excavation. Fossil remains recovered from this locality include six hominin teeth and 28 cranial fragments, all consistent with a single immature hominin individual. The dental morphology of the new specimens supports attribution to H. naledi. This is the first immature individual of H. naledi to preserve morphological details of the calvaria in association with dental evidence. This partial skull provides information about the maturation of H. naledi and will be important in reconstructing the developmental sequence of immature remains from other H. naledi occurrences. This is the third locality described with H. naledi material in the Rising Star cave system and represents a depositional situation that resembles the Lesedi Chamber in some respects. paleoanthropology.org/ojs/index.php/paleo/article/view/64Expanded Explorations of the Dinaledi Subsystem, Rising Star Cave System, South Africa Abstract The Dinaledi Chamber of the Rising Star cave system has yielded a large assemblage of fossil hominin material, attributed to Homo naledi. The unusual taphonomic and geological situation of the assemblage suggested that the remains may have been deliberately deposited in the chamber. However, the route and mechanism of deposition of the remains within the Dinaledi Chamber are still uncertain. During the 2017—2018 field seasons, we expanded explorations of the passages surrounding the Dinaledi Chamber. These explorations improved our understanding of the cave’s spatial complexity, necessitating a revision of the way the spaces are named and described. The work supported the hypothesis that there is no alternate entrance into the system other than the Chute. The work also identified new fossil deposits in several remote passages, three of which contain material attributable to H. naledi. Here, we clarify the definition of the Dinaledi Subsystem and provide terminology for new fossil localities found in this portion of the Rising Star cave system. These results emphasize the complex depositional environment of the Dinaledi Subsystem and raise new questions about the process and timing of the fossil accumulations. paleoanthropology.org/ojs/index.php/paleo/article/view/68
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Post by Admin on Dec 3, 2022 6:26:33 GMT
A momentous discovery in South Africa could turn our understanding of human history on its head. A non-human creature dubbed Homo naledi was discovered nearly a decade ago — and researchers now believe the creature may have had a head start on Homo sapiens, or humans, in using fire as a tool. Renowned paleoanthropologist Lee Berger drew sharp criticism for hypothesizing Homo naledi was deliberately placing its dead in a dark, dangerous underground chamber in the Rising Star caves just outside Johannesburg, South Africa. Some argued it wasn't possible to navigate the complex chamber without light. "And the reason they didn't believe it was because Homo naledi, with its tiny little brain just bigger than a chimpanzee, couldn't have had fire," Berger told CBS News. Homo Naledi, New Species, Unveiled in South Africa The discovery of a new species of human relative, Homo naledi, was unveiled at The Cradle of Humankind. FOTO24/GETTY IMAGES The controlled use of fire was supposedly unique to humans, and for nearly 10 years Berger's team found no evidence the species used fire — until Berger lost over 50 pounds so he could squeeze through the narrow corridors himself for the very first time in August. It was torture all the way down and he was exhausted when he finally reached the bottom. "I looked up. And I realized the ceiling was black. It was burnt. It was covered in soot. It had been right above our heads the entire time," Berger said of his discovery. It's undeniable evidence of fire. The same day, lead investigator and paleoanthropologist Keneiloe Molopyane was making another remarkable find nearby: "Pieces of bone ... burnt bone," she said, which indicated they were eating there. After that, the team saw fire everywhere. "I suspect based on what we're seeing, they're not just carrying fire. I think they're making it," Berger said. "And it's done hundreds of thousands of years, perhaps, before maybe humans were doing it." Berger believes the discovery will challenge our assumptions about human uniqueness. "It should make us think deeply about that way we have placed ourselves on a pedestal as something special, because Homo naledi is beginning to prove that it may have happened many times in the past," he said. "One of the reasons that humans are so harmful to the environment, to this world, is because we think we have some ownership of it," he said. For Molopyane, a South African woman, it's not just about a groundbreaking discovery. "For a very long time, archeology and anthropology, all these discoveries made in Africa, have been made by men, mostly," White men, she said. "That is when we start taking back the narrative as Africans and we get to tell our stories now."
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Post by Admin on Dec 4, 2022 21:58:07 GMT
Berger said in a "serendipitous miracle of palaeontology", when he emerged from the cave, he found Dr Keneiloe Molopyane, who, along with her team, had also discovered a tiny hearth and burnt antelope bones in the Drakensburg chamber. "As I stared at this remarkable coincidence of simultaneous discovery, it made me think about the other spaces. We clearly had been missing things." "It takes us 250 metres of crawling passages and difficult areas. But it is a pristine chamber. It is a chamber that humans only discovered 35 years ago. It's almost untouched by humans." Berger told the audience they found stacked burnt rocks, ash and animal bones. "There are no signs of Homo sapiens … beyond the twilight zone of that system. We are in the deepest part, places humans don't go. The entire floor, as we searched, is covered with burnt animal bones, ash… suddenly, our eyes were opened. Fire is not hard to find. It is everywhere in the system." He said in the early years of the expedition, they found two pieces of ash in the Lesedi chamber. "Archaeologists convinced us that we did not have enough evidence [to prove Homo naledi used fire]. "I assure you that this stuff you are looking at - this heart from the Drakensberg - is actually on the pathway we have been walking and crawling through since the beginning of the expedition. Every adjacent cave system to the chambers, where we believe they were disposing of the dead, they built fires and cooked animals. That's extraordinary. "We are fairly confident to formulate the hypothesis that Homo naledi did exist in a time and place that was primitive, but that it exists in the same place we believe Homo sapiens were sharing parts of Africa. Within this system, it is using and developing widespread fire for a variety of reasons. Berger said this discovery was now opening up the field to more exploration. "Fire was seen as a critical absence of evidence in our arguments about the small-brained hominoid, and I believe we found it in abundance. Over the next several years and decades, we will see if they associate across the places… but it is as clear an association as anyone has. "This is the most extraordinary period of exploration and discovery. "Those of us in the field of paleoanthropology could never have imagined we could have been in this age of exploration. It is gonna continue. The next generation does not have fear of exploration. "Technology is opening spaces and places in a way that none of us could have imagined. It truly is the time not to hinder and say 'don't explore'. This is the time where all of you must encourage us to get out there and see the knowledge."
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Post by Admin on Dec 31, 2022 18:53:42 GMT
Archaeological evidence suggests that Homo naledi, a primitive human species with a chimpanzee-like skull, used fires to cook food and navigate in the darkness of underground caves, despite having a brain one third of the size of ours. “We have massive evidence. It’s everywhere,” says Lee Berger at the University of the Witwatersrand in South Africa. “Huge lumps of charcoal, thousands of burned bones, giant hearths and baked clay.” This find, which is still being analysed and remains controversial, could revolutionise our understanding of the emergence of complex behaviours that had been thought to be the sole domain of large-brained species, such as modern humans and Neanderthals. H. naledi was first discovered in 2013 in the Rising Star cave system in South Africa when two cavers managed to enter a hitherto unexplored chamber via an incredibly tight passage. The surface was littered with thousands of fossil bones. In 2015, these were declared to belong to a new species. We now know that H. naledi was about 144 centimetres tall on average and weighed around 40 kilograms. It had a strange mix of primitive and modern features, with ape-like shoulders, a tiny brain only just bigger than that of a chimpanzee and teeth “more reminiscent of something millions of years old”, says Berger. Yet dating of its fossil remains in 2017 showed that it lived relatively recently, between 230,000 to 330,000 years ago, meaning that it could have co-existed with Homo sapiens, which evolved in Africa around 300,000 years ago. But questions remained about how H. naledi navigated through the labyrinth of underground passages at Rising Star, which are in complete darkness and require complex manoeuvres through gaps in the rock just 17.5 centimetres wide. This inaccessibility means that, in the past decade, only 47 people – all small and slightly built – had managed to access the Dinaledi chamber where H. naledi fossils were first discovered. But in August this year, Berger, who is 188cm tall, decided to risk entering this labyrinth, losing 25 kilograms of weight in preparation. “It’s not a space made for six-feet-two people like me. I’m by far the largest person who’s even been in,” he says. He knew there was a possibility he might not be able to squeeze out again. “I almost died on the way out,” he says. The risk paid off. When Berger entered the Dinaledi chamber and looked up, he realised that there were blackened areas and soot particles on the rock. “The entire roof of the chamber is burnt and blackened,” he says. By coincidence, at the same time that Berger was observing the soot, his colleague Keneiloe Molopyane, also at the University of the Witwatersrand, uncovered a tiny hearth with burnt antelope bones in another part of the cave system, then a large hearth next to it 15cm below the cave floor. Then, in another area called the Lesedi chamber, Berger found a stack of burnt rocks, with a base of ash and burnt bones. This is a remarkable discovery, as many researchers thought it was impossible for such a small-brained hominin to make and use fire within a cave system. Although we have evidence that ancient humans living in what is now Kenya could control fire as far back as 1.5 million years ago, this capacity “is typically associated with larger-brained Homo erectus”, says Berger. H. naledi also seem to have used the space in interesting ways, with “body disposal in one space and cooking of animals in adjacent spaces”, says Berger. “The capacity to make and use fire finally shows us how Homo naledi ventured so deep into dangerous spaces, and explains how they may have moved their dead kin into such spaces, something likely impossible without light. It also hints at a complex naledi culture becoming visible to us.” For Berger, the fire-use discovery has implications that are even more revolutionary. If these small-brained humans with many primitive features were capable of the complex cognition required to make and control fire, then “we’re beginning to see the emergence of a cultural pathway and behaviour that we thought, until this moment, was the domain of [Homo sapiens and Neanderthals],” he says.
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Post by Admin on Dec 31, 2022 20:11:43 GMT
CARTA Presents The Origins of Today's Humans - John Hawks, How Homo Naledi Matters to Our Origins
(01:38 - Main Presentation) Where did we humans come from? When did we become the dominant species on the planet?
Experts take you on an exploration of the last half-decade of new evidence from ancient DNA, fossils, archaeology and population studies that has updated our knowledge about The Origins of Today's Humans. Recorded on 02/21/2020. [Show ID: 35719]
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