HOMO NALEDI
Homo naledi facial reconstruction
In 2015, scientists announced the discovery of a new Homo species from South Africa, named Homo naledi. Regarded as one of the most primitive Homo species yet unearthed, as its brain was only about the size of an orange, it possessed an unusual mix of human-like and non-human-like features such as a human-like skull, slender legs and feet suited for a life on the ground but shoulders, hands and curved fingers adapted for a life in the trees. But don’t let its small brain and ape-like features mislead fool you as it was advanced enough to practice death rituals, scientists said. Researchers unearthed fossils from at least 15 individuals belonging to the new species in the Rising Star cave system in South Africa some 48 kilometers (30 miles) northwest of Johannesburg. [Source: Charles Q. Choi, Live Science, September 10, 2015 ||]
Homo naledi lived between 335,000 and 236,000 years ago, about the same time that modern humans first appeared."It's a very exciting finding," said paleoanthropologist Ian Tattersall at the American Museum of Natural History, who suggested these new hominins might not belong to genus Homo. "I'm a great advocate for the notion that the genus Homo has been made overinclusive," he told Live Science. "I don't like to stuff new things in old pigeonholes. I don't think we have the vocabulary needed to describe the diversity we're seeing in early hominins." ||
Charles Q. Choi wrote in Live Science: The researchers did note that both Homo naledi and the "hobbit" Homo floresiensis had similarly tiny brains. Although the scientists said they could not as yet speculate on any evolutionary links between those two species, the researchers new findings revealed that small-brained, primitive-looking human species with fairly modern features did exist in the past. This suggests that the hobbit is no longer an anomaly, the researchers said.” Scientists detailed their findings online September 10, 2015 in two papers published in the journal eLife and the cover story of the October 2015 issue of National Geographic magazine. ||
As of 2023, over 1,500 skeletal fragments from multiple individuals had been found throughout the 4 kilometers (2.5 mile) -long cave system. The anatomy of H. naledi is well-known due to the remarkable preservation of their remains.
Websites and Resources on Hominins and Human Origins: Smithsonian Human Origins Program humanorigins.si.edu ; Institute of Human Origins iho.asu.edu ; Becoming Human University of Arizona site becominghuman.org ; Hall of Human Origins American Museum of Natural History amnh.org/exhibitions ; The Bradshaw Foundation bradshawfoundation.com ; Britannica Human Evolution britannica.com ; Human Evolution handprint.com ; University of California Museum of Anthropology ucmp.berkeley.edu; John Hawks' Anthropology Weblog johnhawks.net/ ; New Scientist: Human Evolution newscientist.com/article-topic/human-evolution
Homo Naledi Lived 335,000-236,000 Years Ago, Likely Alongside Modern Humans
More fossils of Homo naledi were found in the Rising Star Cave system in South Africa and the previous bones and other artifacts found help dated the species to between 335,000 and 236,000 years ago, pretty much placing them side by side with early modern humans. A series of papers published in the journal eLife addressed many issues related to Homo naledi, chief among them its age, which turned out to much younger than previously thought. [Source: Léa Surugue, International Business Times, May 9, 2017]
Léa Surugue wrote in the International Business Times: “A team led by Paul Dirks from the James Cook University in Australia measured the concentration of radioactive elements and the level of radioactive decay in three fossilised teeth, as well as in the sediments and rocks inside the Dinaledi Chamber – where the fossils were first discovered in 2013-14. This is at present one of the most precise and reliable method for dating samples, made all the more robust here by the fact the scientists had independent laboratories around the world carry the analyses. The experts didn't know which samples came from the cave and which were 'controls'. The findings suggest that H Naledi fossils are between 236,000 and 335,000 years old. This mean that the species might have coincided with the earliest members of our own species – Homo Sapiens – which most likely evolved around that time.
“In a separate study, another team also reports on the discovery of new fossils in a deep chamber of the Rising Star Cave system (nearly 100 metres away from the Dinaledi chamber) – known as the Lesedi Chamber. About 130 fossils were found in the Lesedi chamber, likely belonging to three individuals, one child and two adults. One of the adults is particularly well preserved, with a nearly complete skeleton. It has been called "Neo" – the Sesotho word meaning "a gift". The researchers believe they will find more remains as the excavation progresses.”
Homo Naledi Characteristics
Jamie Shreeve wrote in National Geographic: “ A composite skeleton reveals H. naledi’s overall body plan. Its shoulders, hips, and torso hark back to earlier ancestors, while its lower body shows more humanlike adaptations. The skull and teeth show a mix of traits. “Weird as hell,” paleoanthropologist Fred Grine of the State University of New York at Stony Brook later said. “Tiny little brains stuck on these bodies that weren’t tiny.” The adult males were around five feet tall and a hundred pounds, the females a little shorter and lighter. “The message we’re getting is of an animal right on the cusp of the transition from Australopithecus to Homo,” Berger said....“Everything that is touching the world in a critical way is like us. The other parts retain bits of their primitive past.” [Source: Jamie Shreeve, National Geographic, September 2015 /+]
Charles Q. Choi wrote in Live Science: “On average, Homo naledi stood about 5 feet (1.5 m) tall and weighed about 100 lbs. (45 kilograms). It had a tiny brain, only about 30.5 cubic inches (500 cubic centimeters) in size, making the organ about as large as the average orange. That's smaller than the modern human brain, which is about 73 to 97 cubic inches (1,200 to 1,600 cubic cm), but comparable in size to the brain of Australopithecus sediba. Australopithecines are likely the ancestors of the human lineage. [Source: Charles Q. Choi, Live Science, September 10, 2015 ||]
Homo naledi right hand
“Homo nalediwas a surprising blend of primitive and modern hominin traits. For example, "the hands suggest tool-using capabilities," study co-author Tracy Kivell of the University of Kent in England said in a statement. Many scientists have long believed that tool use accompanied a boost in brain size, but Homo naledi's brain was rather small. ||
“In addition, its feet are virtually indistinguishable from those of modern humans. This, together with its long legs, suggest the species was adapted for a life on the ground involving long-distance walking. However,; its fingers were extremely curved, more curved than those of nearly any other species of early hominin, which hints at a life suited for climbing trees. "Modern humans are really unusual in that walking on two legs is pretty much all we do," study co-author Will Harcourt-Smith, a paleoanthropologist at Lehman College in the Bronx and the American Museum of Natural History in New York, told Live Science. "Homo naledi probably spent most of its time walking on two legs, but also spent some proportion of its time up in trees — whether to escape predators or nest at night, we don't know." ||
“Furthermore, Homo naledi's small teeth, slender jaws and many skull features are similar to those of the earliest known members of Homo, but its shoulders are more similar to those of apes. "The combination of anatomical features we see in this creature is not like any we've ever seen before," study co-author John Hawks, a paleoanthropologist at the University of Wisconsin–Madison, told Live Science.”
Homo Naledi Climbed Trees and Walked
Homo naledi, had hands and feet adapted for a life both on the ground and in the trees, which among other things made it walk with a swagger. Charles Q. Choi wrote in Live Science: “Scientists investigated the hands and feet of H. naledi to learn more about a key shift in human evolution — the move from a life of climbing trees to one spent walking on the ground. Modern humans dominate the planet partly because walking upright frees their hands for tool use, scientists have found. The researchers analyzed more than 150 H. naledi hand bones, including a nearly complete adult right hand that was missing just one wrist bone. They found the species shared a long, robust thumb and wrist architecture with modern humans and Neanderthals, potentially giving the hand a precise, forceful grip that may have been useful for tool use. [Source: Charles Q. Choi, Live Science, October 6, 2015]
“However, its fingers were longer and more curved than most australopithecines — indeed, more curved than those of nearly any other species of early hominin. This quality hints at a life suited for moving and climbing through trees. The scientists detailed their findings on H. naledi's hands and feet online in October 6, 2015 in two papers in the journal Nature Communications. "The tool-using features of the H. naledi hand, in combination with its small brain size, has interesting implications for what cognitive requirements might be needed to make and use tools, and, depending on the age of these fossils, who might have made the stone tools that we find in South Africa," Tracy Kivell at the University of Kent in England, lead author of one of the two H. naledi papers, said in a statement.
with a Swagger
reconstruction of Homo naledi foot
“The scientists also investigated 107 H. naledi foot bones, including a nearly complete adult right foot. They found the ancient hominin's foot shared many features with the modern human foot, suggesting that it was well-suited for standing and walking on two feet. "The foot is not entirely humanlike, but it's more humanlike than not," William Harcourt-Smith, a paleoanthropologist at Lehman College in the Bronx and the American Museum of Natural History in New York, told Live Science. "I think it would've been very good at walking on the ground."
“However, the H. naledi foot had toes that were more curved than those of modern humans, supporting the notion that the hominin was also relatively adept at life in the trees. "H. naledi wouldn't have been in any way as proficient as chimpanzees or much more primitive hominins at climbing trees, but it still would be better-suited than we are," said Harcourt-Smith, lead author of the other H. naledi paper. [Source: Charles Q. Choi, Live Science, October 6, 2015]
“Intriguingly, H. naledi's pelvis was more like that of australopithecines such as Lucy, flaring outward more than that of modern humans. "This configuration moved the hip muscles away from the hip joints and gave them more leverage in walking — perhaps more of an advantage than humans have today," study co-author Jeremy DeSilva, an anthropologist at Dartmouth University, said in the statement. "Over time, the architecture of the pelvis evolved and expanded to allow the birth of larger-brained babies."These findings suggest that early human evolution involved many experiments "on different ways to be bipedal," Harcourt-Smith said. Scientists are still unsure how exactly H. naledi might have walked differently from modern humans. "But there's absolutely no doubt that its gait would have been different," Harcourt-Smith said.”
Homo Naledi Buried Their Dead
Marley Brown wrote in Archaeology Magazine: Newly uncovered remains of H. naledi individuals from other chambers deeper within the Rising Star system have now led researchers to conclude that the H. naledi population may have deliberately interred their dead in the caves, challenging conventional notions of the behavior of early humans with small brains, who are presumed to have had limited cognitive abilities. [Source: Marley Brown, Archaeology Magazine, May/June 2022
Paleoanthropologist Juliet Brophy of Louisiana State University says there is no evidence that H. naledi lived in the Rising Star caves—no domestic sites tied to the hominins have been discovered there. It’s likely, she says, that a population of H. naledi lived nearby and knew the caves. The team has now discovered H. naledi specimens in three cave chambers within the system, including at least 15 individuals in the Dinaledi chamber and three in another known as the Lesedi chamber. Among those in the Lesedi chamber was an adult male whom the team named Neo. According to Brophy, Neo’s remains were concentrated in a small area of the chamber and appear to have been placed there deliberately after his death.
In a third chamber, called U.W.110, the team discovered the skull of a young H. naledi female they named Leti, who died between the ages of four and six. This chamber is more than 260 feet from the entrance to the cave system and is so cramped that the cavers had to excavate upside down. Brophy says there is no evidence on Leti’s skull, or on any H. naledi remains, indicating that the hominins were victims of attacks by predators, such as tooth or gnaw marks, or that any of the fossils were brought into the cave system by flooding. “Someone went to a lot of trouble to deposit this skull in a really remote area,” Brophy says. “When we first told people in the field that we thought H. naledi was deliberately depositing their dead in Rising Star, we were met with resistance, but this is very compelling evidence that they went to a lot of effort.” H. naledi, Brophy says, visited these caves over an extended period to bury multiple generations of their dead, some of whom were as young as one or two and couldn’t possibly have found their way deep into the cave system on their own.
Homo naledi skeleton
Charles Q. Choi wrote in Live Science: “Prior research had uncovered another possible instance of an extinct human species disposing of its dead, in Atapuerca in Spain. This site also contained remains thrown to the bottom of a cave. "Those hominins were much larger-brained, much closer to modern humans in brain size," Harcourt-Smith said. "There's debate as to which species was at Atapuerca — probably Homo heidelbergensis, a close relative of Neanderthals. “However, this is the first time such behavior with the dead has been seen with such a primitive hominin— that is, one dating back so early in the human family tree. "It's just an extraordinary discovery, a game-changer to see this very advanced behavior used back then," Harcourt-Smith said. It remains unknown why Homo naledi disposed of its dead in this way. "We can spin a lot of yarns," Harcourt-Smith said. Maybe it buried the dead out of reverence, he said, or "maybe to get rid of things that were smelling. Maybe another species was throwing them down." [Source: Charles Q. Choi, Live Science, September 10, 2015 ||]
Brown wrote: The notion that H. naledi developed a culture of burying their dead has been met with incredulity by some who have questioned whether, with their small brains, the hominins could have developed a concept of an afterlife. Both Brophy and her colleague John Hawks, a paleoanthropologist at the University of Wisconsin–Madison, however, believe this is unnecessary to explain the behavior the team has observed. “Every culture on Earth has mortuary behavior, whether or not their burial practices are related to religion or an afterlife—even nonhuman social mammals undergo emotional and social changes when they encounter a dead individual,” says Hawks. “The appearance of mortuary practices and special behavior around the dead goes back much further in our evolution than any set of beliefs that exists in the world today.”
Homo Naledi Squeezed into the Caves to Deliberately Bury Their Dead
H. naledi was around 122 centimeters (four feet 10 inches) tall and weighed between 45 to 50 kilograms (100 and 110 pounds). Its smaller size and head allowed it to access parts of the cave system where most modern humans cannot fit. It has been theorized that H. naledi individuals climbed through the narrow passages to get into the cave and deliberately buried their dead there.
At a news conference in June 1, 2023, Berger and his colleagues with the Rising Star program lead, backed up their claim with three studies published on the preprint server bioRxiv, that together put forth the most substantial evidence so far that H. naledi purposefully buried their dead and created meaningful engravings on the rock above the burials. [Source: Kristina Killgrove, Live Science, June 6, 2023]
Kristina Killgrove of Live Science wrote: The new research describes two shallow, oval-shaped pits on the floor of one cave chamber that contained skeletal remains consistent with the burial of fleshed bodies that were covered in sediment and that then decomposed. One of the burials may even have included a grave offering: a single stone artifact was found in close contact with the hand and wrist bones. Berger said in the press conference that "we feel that they've met the litmus test of human burials or archaic human burials." If accepted, the researchers' interpretations would push back the earliest evidence of purposeful burial by 100,000 years, a record previously held by Homo sapiens.
Homo Naledi Artwork for Their Dead
Homo naledi, whose brain was one-third the size of ours, also appeared to engrave the cave walls near the burials around 300,000 years ago, according to research Berger presented. This overturned long-held theories that only modern humans and our Neanderthal cousins could perform complex activities like burials and honoring the dead. [Source: Kristina Killgrove, Live Science, June 6, 2023]
Kristina Killgrove of Live Science wrote: The discovery of abstract engravings on the rock walls of the Rising Star Cave system also signals that H. naledi had complex behavior, the researchers suggest in another new preprint. These lines, shapes, and "hashtag"-like figures appear to have been made on specially-prepared surfaces created by H. naledi, who sanded the rock prior to engraving it with a stone tool. The line depth, composition and order suggest that they were purposefully made rather than formed naturally.
Among the engravings found in the Hill Antechamber burial chamber was an upside-down cross shape. There is also a material applied over the surface to highlight the non-geometric images in low light. "There are burials of this species directly below these [engravings]," Berger said, which suggests this was a H. naledi cultural space. "They've intensely altered this space across kilometers of underground cave systems."
In another preprint, Agustín Fuentes, an anthropologist at Princeton University, and colleagues explore why H. naledi used the cave system. "The shared and planned deposition of several bodies in the Rising Star system" as well as the engravings are evidence that these individuals had a shared set of beliefs or assumptions surrounding death and may have memorialized the dead, "something one would term 'shared grief' in contemporary humans," they wrote. Other researchers, however, are not fully convinced by the new interpretations.
Homo naledi lower jaws
Uncovering Evidence of Deliberate Burial by Homo Naledi
Lee Berger wrote in National Geographic: By early 2022 the possibility that we were uncovering H. naledi burials had grown stronger. We had H. naledi fossils from many different areas in Rising Star, including the Puzzle Box, Dinaledi itself, and another chamber more than 328 feet away. Scans of one rocky block that we had carried out of the cave system revealed a child’s body, almost certainly of H. naledi, curled up in a space smaller than a laundry basket, with the remains of two or three others thrown into the same hole or right next to it. A crescent-shaped object denser than the bones—a possible stone tool—was sitting right next to the most complete skeleton’s hand.
As Marina and Becca removed sediment one spoonful at a time from the area that Bones and I were puzzling over on the live stream, they uncovered a concentration of bones about as large as a medium-size suitcase. Oddly, the surrounding sediment contained only a few fragments—or no bones at all. It didn’t make sense. If the bones had flowed into the chamber, why had the fossils clustered? Why was there empty space between them?
For years we had worked in Rising Star knowing that H. naledi had occupied these spaces, and we had reason to suspect that they used Dinaledi as a repository for their remains. But “deliberate body disposal”—the language we had all carefully used in our earlier work—is very different from “burial.” In our 2015 papers describing H. naledi, we suggested that the bodies found in Dinaledi could have been either carried into the cave or dropped down, perhaps through the chimney-like passage we called the Chute. Burial, on the other hand, is something more intentional: a body being purposely interred and then covered.
Archaeologists have found surprisingly little evidence of burial among the earliest members of our species. The oldest clear cases were found in Israel, believed to be between 120,000 and 90,000 years old. Neanderthals also sometimes buried their dead, although the best evidence of this behavior comes from fairly late in their existence, less than 100,000 years ago. Our tightest constraints on the age of H. naledi date further back, to between 335,000 and 241,000 years ago.
H. naledi was Homo, but with a brain one-third the size of ours, it was far from human. Scientists might accept that large-brained hominins like Neanderthals could exhibit complex behavior, but the idea that H. naledi engaged in anything of the sort was a harder pill to swallow. It was a radical idea, then, to propose that Rising Star might contain a burial site. Burial was too human an activity: It took planning, a shared intention across a social group, knowledge of the permanence of death.
Doubts That Homo Naledi Deliberately Buried Their Dead
Some experts say the evidence isn't enough to conclude H. naledi buried or memorialized their dead. "I can see where they are connecting the dots with this data and do think it was worth reporting, but it should have been done with many more caveats," Sheela Athreya, an anthropologist at Texas A&M University, told Live Science. "Humans may have made tick marks on rocks. That's not enough to contribute to this conversation about abstract thinking," Athreya said.
Homo naledi's 737 known elements
There are also questions about how H. naledi got into the Rising Star Cave system; the assumption that it was difficult underlies many of the researchers' interpretations of meaningful behavior. "Did they get in there the same way that we are getting in there, or might there have been another way in?" Jonathan Marks, an anthropologist at the University of North Carolina at Charlotte who was not involved in the research noted to Live Science. "This is a job for archaeology — lots of archaeology."
Insights from Homo Naledi on Human Evolution
In 2017, the scientific team that found Homo Naledi said that its latest discoveries and insights published in May 2017 in Elife would change the way we look at human evolution. Team leader, paleoanthropologist Lee Berger of Johannesburg’s University of the Witwatersrand, said that it was possible that some artifacts and behaviors attributed only to early humans — things like tools, adornments and burial of the dead — might actually be the work of Homo naledi or some other hominin. The date when Homo naledi lived — 236,000-335,000 years ago — “corresponds with when most archeologists and paleoanthropologists — and genetics — is suggesting we see the rise of modern humans,” he said. “And a lot of people argue that that rise was right here in southern Africa. But now there’s another species here. Everything is very complex from this moment onward.” [Source: Anita Powell, VOA News, May 9, 2017]
Among the cache of fossils found in the second chamber, Berger said was is a nearly complete adult skull, which scientists nicknamed Neo — the SeSotho word for “gift.” “Neo gives us a real look at what the body and face of this incredible new species looks like. It tells us we were a little bit wrong,” he said. “We had guessed there was a little bit more nose. Actually Homo Naledi has a little flatter, even more primitive face than we thought, which is one of the reasons we placed it further back in the family tree of relatedness to early hominins. It’s clear that parts of Homo Naledi from Neo are very, very, very primitive, amongst the most primitive we’ve seen in hominins. And other parts are surprisingly advanced. They, in fact, are comparable mostly with us, as humans.”
Jennifer Raff wrote in The Guardian: “Many people tend to think of human evolution as a very linear path: from primitive creatures more or less directly to ourselves. But for most of the history of evolution, there were multiple species of hominins running (or climbing) around the African landscape, each with their own unique physical adaptations to the challenges of survival. As with all evolutionary experiments, some of these adaptations proved more successful than others. Based on careful study of fossils spanning millions of years in Africa, paleoanthropologists thought they had a good understanding of how the experiment’s results unfolded. Human evolution wasn’t a straight progression by any means, but more like a complicated bush, with branches leading off in many directions. Still, there were definite trends that made their way into our textbooks. Hominin lineages with some trait combinations died off without leaving any descendants. In the lineages that persisted, brains got bigger, legs longer, arms shorter, fingers less curved, teeth smaller. [Source: Jennifer Raff, The Guardian, May 23, 2017]
“It mostly made sense, and the new species discovered in a South African cave in 2015 seemed initially to fit within this paradigm. Homo naledi, as it was called, had some very primitive morphological features that meant it was likely very ancient indeed - possibly 2 million years ago, close to the root of our genus Homo. | “But the recent discovery of a new set of H. naledi remains, in a separate chamber of the same cave system, and the first direct dates of the earlier H. naledi skeletons, has challenged this tidy story. Shockingly, the remains dated to just 236,000-335,000 years ago. This makes H. naledi very young: contemporaneous with early modern H. sapiens elsewhere in Africa. Yet, as the new fossils confirmed, H. naledi possessed a weird mosaic of primitive (ancient) and derived (more human-like) traits, such as small brain sizes (roughly a third of the size as ours: you can see the difference in the picture above) but human-like hands and limbs. |=|
skull features
“One reason this has paleoanthropologists in an uproar is that it means some features, such as small brain sizes, persisted long after they thought it possible. Berger et al. suggests that in light of this, we perhaps should be concerned about fossils which we have assigned to species on the basis of morphology rather than direct dates. If some remains have been misclassified, we may need to change our ideas about how different hominin lineages evolved. Another implication of these dates is that these hominins were around South Africa when stone tools began to be made. While they haven’t been found in association with any tools in the cave, we must still be open to the possibility that these small brained hominins could have made them. Finally, whether or not the H. naledi remains were deliberately buried inside the cave remains an extremely contentious issue among paleoanthropologists. These possibilities - both still unverified - pose a “robust challenge” for archaeologists to grapple with.
“Notably, there are some things that these fossils won’t change: 1) We are indeed the product of evolution (I’m anticipating some of the comments on this post inevitably challenging evolution. Sorry guys, the evidence is incontrovertible and the fact that scientists change their minds as to the details when new discoveries are made speaks to the strength of the scientific process, not the weakness of the theory). 2) Humans originated in Africa, 3) There were multiple kinds of hominins co-existing for much of human evolution, 4) Humans are likely descended from H. erectus, with subsequent ancestry from some of the other kinds of hominins (Denisovans, Neanderthals, and probably others). |=|
“So where does H. naledi fit within the overall picture of human evolution in Africa? It’s still unresolved. Berger et al. suggested three scenarios: First, H. naledi belongs to one of the lineages leading to H. habilis, H. rudolfensis, H. floresiensis, and A. sediba. Alternatively, H. naledi is younger - a sister lineage to the clade that contains H. erectus and the big-brained later hominins (including H. sapiens). The final scenario is that H. naledi is even younger still - a sister lineage to H. sapiens. Another possibility is that H. naledi is the result of hybridisation between two or more lineages, perhaps one related to humans and one related to Australopithecines. |=|
“The unusual combination of primitive and derived features of H. naledi make distinguishing between the above scenarios difficult without genetic evidence. If we could get a genome from one or more H. naledi individuals, we could determine the phylogenetic relationship between it and the big-brained hominins: H. sapiens and H. neanderthalensis (we don’t yet know the brain size of Denisovans). This would tell us whether or not human populations had ancestry from this group (and perhaps others). |=|
cranial comparisons
Image Sources: Wikimedia Commons
Text Sources: National Geographic, New York Times, Washington Post, Los Angeles Times, Smithsonian magazine, Nature, Scientific American. Live Science, Discover magazine, Discovery News, Natural History magazine, Archaeology magazine, The New Yorker, Time, BBC, The Guardian, Reuters, AP, AFP and various books and other publications.
Last updated April 2024