BY CAROLINE SAVOIE | STAFF WRITER
NOV 14, 2021 -
Juliet Brophy, LSU biological anthropology professor, worked with a team of international researchers to analyze bone fragments from early human ancestors who lived over 300,000 years ago.
Provided by LSU
Guy Berger, who led a team through the Rising Star cave system in South Africa, held a reconstructed model of an early human ancestor’s skull. No bigger than an orange, the skull belongs to a child between the ages of 4 and 6 years old who died approximately 250,000 years ago.
Provided by LSU
Juliet Brophy, LSU biological anthropology professor, worked with a team of international researchers to analyze bone fragments from early human ancestors who lived over 300,000 years ago.
Provided by LSU
Archaeologists and paleoanthropologists had to carefully navigate the Rising Star cave system in South Africa, a hotbed for early human ancestors’ remains. One researcher, Juliet Brophy, said the narrow tunnels and crevices within the cavernous system calls for creative methods to excavate fossils.
Provided by LSU
When recreational cave explorers stumbled upon fossils on the surface of the Rising Star caves in South Africa, they unknowingly introduced archaeologists to an anthropological gold mine.
In the years since their discovery, researchers spent countless hours excavating and studying remains from the cave. What they found helps fill in the blanks about how the early human ancestor Homo naledi lived over 300,000 years ago.
LSU biological anthropology professor Juliet Brophy published details about how this early human species behaved, matured and evolved in the scientific journal PaleoAnthropology earlier this month. Her team made a rare discovery: the skull and teeth of a Homo naledi child who died 250,000 years ago somewhere between age 4 and 6.
She said researchers named the child Leti, short for “Letimela” which means “the lost one” in Setswana, a language spoken in the region.
Brophy was one researcher on a team of 21 international archaeologists and paleoanthropologists who examined the child’s 28 skull fragments and six teeth.
“This is the first partial skull of a child of Homo naledi ever recovered, and this begins to give us insight into all stages of life of this remarkable species,” she said.
Brophy said researchers found the fossils in a remote part of the cave, 39 feet away from other Homo naledi remains, which suggests someone placed the child’s body there on purpose. Because Leti’s remains have no signs of carnivore or scavenging damage, the team had to hypothesize how Leti’s skull came to rest, alone, in such a narrow, inaccessible part of the cave.
“We believe that members of the same species, of the same community, put Leti that far into the cave,” Brophy said.
Guy Berger, a professor at the University of Witwatersrand in Johannesburg, led the team through the cave system.
“The discovery of a single skull of a child, in such a remote location within the cave system adds mystery as to how these many remains came to be in these remote, dark spaces of the Rising Star Cave system,” Berger said. “It is just another riddle among many that surround this fascinating extinct human relative.”
Brophy was 34 years old when Berger hired her to analyze the first Homo naledi remains in 2014 with a team of early career scientists. They determined the fossils needed to be classified as a new species.
“Naming a newfound species was simply incredible,” she said. “We saw such an interesting mix of features in these remains that we couldn’t classify them as any known species. It was like putting a puzzle together.”
The initial discovery, first announced in 2015, comprises 1,550 specimens belonging to at least 15 different individuals spanning several age groups. Brophy said finding a skull like Leti’s is extremely rare, as juvenile remains are notoriously thin and fragile.
Berger said studying the ancestral remnants raises questions about the current understanding of human history.
“Homo naledi is clearly a primitive species, existing at a time when previously we thought only modern humans were in Africa,” he said. “Its very presence at that time and in this place complexifies our understanding of who did what first concerning the invention of complex stone tool cultures and even ritual practices.”
Brophy said the Rising Star cave system is one of the richest sites of discovery for hominin fossils in the world. She said researchers are still navigating and excavating the cave system in hopes of figuring out whether or not the caves were used as Homo naledi’s burial grounds.
She said Leti, along with the 15 other individuals they’ve found, unlocks a view into the world before modern humans, a world that might include rituals like the ones still practiced today.
Provided by LSU
When recreational cave explorers stumbled upon fossils on the surface of the Rising Star caves in South Africa, they unknowingly introduced archaeologists to an anthropological gold mine.
In the years since their discovery, researchers spent countless hours excavating and studying remains from the cave. What they found helps fill in the blanks about how the early human ancestor Homo naledi lived over 300,000 years ago.
LSU biological anthropology professor Juliet Brophy published details about how this early human species behaved, matured and evolved in the scientific journal PaleoAnthropology earlier this month. Her team made a rare discovery: the skull and teeth of a Homo naledi child who died 250,000 years ago somewhere between age 4 and 6.
She said researchers named the child Leti, short for “Letimela” which means “the lost one” in Setswana, a language spoken in the region.
Brophy was one researcher on a team of 21 international archaeologists and paleoanthropologists who examined the child’s 28 skull fragments and six teeth.
“This is the first partial skull of a child of Homo naledi ever recovered, and this begins to give us insight into all stages of life of this remarkable species,” she said.
Brophy said researchers found the fossils in a remote part of the cave, 39 feet away from other Homo naledi remains, which suggests someone placed the child’s body there on purpose. Because Leti’s remains have no signs of carnivore or scavenging damage, the team had to hypothesize how Leti’s skull came to rest, alone, in such a narrow, inaccessible part of the cave.
“We believe that members of the same species, of the same community, put Leti that far into the cave,” Brophy said.
Guy Berger, a professor at the University of Witwatersrand in Johannesburg, led the team through the cave system.
“The discovery of a single skull of a child, in such a remote location within the cave system adds mystery as to how these many remains came to be in these remote, dark spaces of the Rising Star Cave system,” Berger said. “It is just another riddle among many that surround this fascinating extinct human relative.”
Brophy was 34 years old when Berger hired her to analyze the first Homo naledi remains in 2014 with a team of early career scientists. They determined the fossils needed to be classified as a new species.
“Naming a newfound species was simply incredible,” she said. “We saw such an interesting mix of features in these remains that we couldn’t classify them as any known species. It was like putting a puzzle together.”
The initial discovery, first announced in 2015, comprises 1,550 specimens belonging to at least 15 different individuals spanning several age groups. Brophy said finding a skull like Leti’s is extremely rare, as juvenile remains are notoriously thin and fragile.
Berger said studying the ancestral remnants raises questions about the current understanding of human history.
“Homo naledi is clearly a primitive species, existing at a time when previously we thought only modern humans were in Africa,” he said. “Its very presence at that time and in this place complexifies our understanding of who did what first concerning the invention of complex stone tool cultures and even ritual practices.”
Brophy said the Rising Star cave system is one of the richest sites of discovery for hominin fossils in the world. She said researchers are still navigating and excavating the cave system in hopes of figuring out whether or not the caves were used as Homo naledi’s burial grounds.
She said Leti, along with the 15 other individuals they’ve found, unlocks a view into the world before modern humans, a world that might include rituals like the ones still practiced today.
Child Skull of Enigmatic Ancient Human Found in South African Cave
Scientists are struggling to understand how the 250,000-year-old fossil ended up in such a remote, hard-to-reach part of the cave system.
By George Dvorsky
11/04/21
Reconstructed child skull of H. naledi. Dark portions are inferred portions of the skull.
This view of the reconstructed skull, held by a human hand, provides a sense of scale. Image:
A selection of the recovered skull fragments.
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.”
For these reasons, the scientists are content to say that the fossil is somewhere between 236,000 and 335,000 years ago, but Brophy added that the fossil could still potentially be dated in the future.
Multiple views of a molar belonging to the skull.
Scientists are struggling to understand how the 250,000-year-old fossil ended up in such a remote, hard-to-reach part of the cave system.
By George Dvorsky
11/04/21
Reconstructed child skull of H. naledi. Dark portions are inferred portions of the skull.
Image: University of the Witwatersrand, Johannesburg.
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.
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.
This view of the reconstructed skull, held by a human hand, provides a sense of scale. Image:
Image: University of the Witwatersrand, Johannesburg.
“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.
“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.
A selection of the recovered skull fragments.
Image: University of the Witwatersrand, Johannesburg.
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.”
For these reasons, the scientists are content to say that the fossil is somewhere between 236,000 and 335,000 years ago, but Brophy added that the fossil could still potentially be dated in the future.
Multiple views of a molar belonging to the skull.
Image: University of the Witwatersrand, Johannesburg.
As the first known skull belonging to a H. naledi child, the scientists could only compare it to other adults of the same species, but it did match in some important respects. Same for the teeth in terms of shape, size, and form. The volume of Leti’s brain was estimated at around 450 to 610 cubic centimeters, which, based on the presumed age, is approximately 90% to 95% the size of an adult H. naledi brain.
One of the more interesting aspects of the discovery is where the fossil was found—a hard-to-reach section of the cave. In the press release, biological anthropologist Marina Elliott, who participated in the initial discovery of H. naledi, said it was “one of the more challenging sites with hominin fossils we have had to get to in the Rising Star system.” How Leti’s skull ended up on that spot remains a mystery.
“However, there is no visible predator or scavenger damage on any parts of the skull, nor is there any evidence that suggests that the sediments surrounding Leti have been moved by water or other means that may have resulted in the depositing of the skull into this remote location,” Brophy told me. “Therefore, we hypothesize that Leti was placed in the passage by another individual.”
The reason for such a particular placement may have something to do with the way ancient peoples treated the dead. Early hominins are known to have placed bodies deep inside of caves, either as some kind of death ritual or to keep them away from animals (or a combination of both, or for reasons unknown). Interestingly, the placement of Leti’s skull is similar to the treatment of an adult H. naledi, nicknamed Neo, whose remains were found in Lesedi Chamber of the Rising Star cave complex.
Looking ahead, the team is hoping to learn more about Leti, such as their diet, an explanation for why some teeth were chipped, and possible relation to other specimens found in Rising Star cave complex
As the first known skull belonging to a H. naledi child, the scientists could only compare it to other adults of the same species, but it did match in some important respects. Same for the teeth in terms of shape, size, and form. The volume of Leti’s brain was estimated at around 450 to 610 cubic centimeters, which, based on the presumed age, is approximately 90% to 95% the size of an adult H. naledi brain.
One of the more interesting aspects of the discovery is where the fossil was found—a hard-to-reach section of the cave. In the press release, biological anthropologist Marina Elliott, who participated in the initial discovery of H. naledi, said it was “one of the more challenging sites with hominin fossils we have had to get to in the Rising Star system.” How Leti’s skull ended up on that spot remains a mystery.
“However, there is no visible predator or scavenger damage on any parts of the skull, nor is there any evidence that suggests that the sediments surrounding Leti have been moved by water or other means that may have resulted in the depositing of the skull into this remote location,” Brophy told me. “Therefore, we hypothesize that Leti was placed in the passage by another individual.”
The reason for such a particular placement may have something to do with the way ancient peoples treated the dead. Early hominins are known to have placed bodies deep inside of caves, either as some kind of death ritual or to keep them away from animals (or a combination of both, or for reasons unknown). Interestingly, the placement of Leti’s skull is similar to the treatment of an adult H. naledi, nicknamed Neo, whose remains were found in Lesedi Chamber of the Rising Star cave complex.
Looking ahead, the team is hoping to learn more about Leti, such as their diet, an explanation for why some teeth were chipped, and possible relation to other specimens found in Rising Star cave complex
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