I want to 3D print the skull of the newly discovered Homo naledi.
The printing data can be found here: http://morphosource.org/index.php/Detail/MediaDetail/Show/media_id/7300
Where can I find the exact size of the skull so that I get a 1:1 copy? Google was of no help.
Based on Figure 11 in the original publication (scale bar = 10 cm):
The anteroposterior length of the skull should be about 16.3 cm. I just printed out the figure and did the conversion.
So check that your 3D printing software estimates a little over 16 cm for the length from brow ridge to occipital. The full reconstructed skull will be longer of course, but this should give you a concrete measurement to compare to.
From my research, I can deduce that the cranial volume for males is
560 cm3 (34 cu in)
465 cm3 (28.4 cu in) for females
Note: These skulls are approximately half the volume of modern human skulls average Homo erectus skulls are
900 cm3 (55 cu in)
I don't think you would need the area for 3-D printing, but you can use the volume!
Our editors will review what you’ve submitted and determine whether to revise the article.
Homo naledi, (Latin and Sesotho mix: “star man”) extinct species of human, initially thought to have evolved about the same time as the emergence of the genus Homo, some 2.8 million to 2.5 million years ago, during the Pliocene (5.3 million to about 2.6 million years ago) and Pleistocene (about 2.6 million years ago to 11,700 years ago) epochs. Subsequent analyses of the fossils in the only known location where the remains of the species have been found suggest that H. naledi may have been significantly younger or persisted deep into the Pleistocene before dying out. H. naledi is known from more than 1,500 fossil specimens found in excavations of the Rising Star cave complex in South Africa’s Transvaal region—the remains of at least 15 males and females of various ages—that were described in 2015.
Anatomic features that H. naledi had in common with other members of Homo include reduced cheek teeth and similar jaws and feet. Other features, including the pelvis, shoulder girdle, and femur, are more like those found in Australopithecus. Although the skull shape in H. naledi is not like that in Australopithecus, the brain size of 560 cc (560 cubic cm, or 34 cubic inches) aligns with Australopithecus and other hominin species that were extant between 4 million and 2 million years ago. Paleontologists speculated that the discovery of such a large collection of remains deep inside the Rising Star cave complex suggests that the species was capable of ritualistic thought, a trait previously thought to have arisen much later in human evolution.
Comprehensive analyses of the remains and the surrounding sediment and rock indicate that H. naledi was much younger than age estimates based on morphological similarities suggest. Uranium-thorium dating of the rock matrix combined with an analysis of three teeth using electron spin resonance revealed that the age of the remains was between 335,000 and 236,000 years old.
Fossil find suggests Homo erectus emerged 200,000 years earlier than thought
Stephanie Baker, University of Johannesburg Andy I.R. Herries, La Trobe University Angeline Leece Jesse Martin, La Trobe University Matthew Caruana, University of Johannesburg, and Renaud Joannes-Boyau, Southern Cross University
Homo Naledi, an Ancient Hominin, Had Human-Like Features In Its Brain
In recent years, scientists have shaken off the myth that the size of the human brain rocketed us to the top of the food chain. While the human brain is three times larger than that of chimpanzees and bonobos, it’s increasingly understood that it’s the brain’s morphology and molecular activity — not size — that dictates intelligence. A study on the ancient hominin Homo naledi, released Monday in Proceedings of the National Academy of Sciences, presents evidence supporting this theory, showing that it’s the design of the Homo brain that set humans and our prehistoric relatives apart as a genus.
The new study, which used H. naledi remains between 236,000 and 335,000 years old, suggests that while the hominins had small brains and primitive bodies compared to that of other Homo species (like humans, the Neanderthals, and the “hobbit” H. floresiensis), their cranial anatomy was actually quite similar. That similarity lives on in human brains today and suggests that this brain organization was likely present in the common ancestor we share with the H. naledi.
“The fact that Homo naledi’s brain had characteristics consistent with modern human brains despite its small size reconfirms that brain organization is likely more important than brain size — and that the two, brain size and morphology, are not necessarily linked,” study co-author and Des Moines University associated professor Heaver Garvin, Ph.D. tells Inverse. “This is all despite the fact that H. naledi also exhibits some anatomical features consistent with climbing and a brain size about one-third of ours.”
Garvin and her colleagues, led by Columbia University anthropologist Ralph Holloway, Ph.D. compared H. naledi’s brain morphology to that of other hominids — a group that includes all modern and extinct great apes — by creating models from four H. naledi cranial fragments. These “endocasts” are digital impressions of the interior of the skull, which allowed the scientists to study the brain’s cranial surface features.
The details they were able to extract, says Gavin, were “extraordinary.” Like that of modern humans, the H. naledi brain contained a frontal operculum but no fronto-orbial sulcus, a feature found in the brains of apes and Australopithecus, an early human species that lived between 3.86 and 2.95 million years ago that includes the infamous Lucy. Like H. naledi, humans and other Homo species also lack a fronto-orbial sulcus. The endocasts also showed that H. naledi had asymmetry in its occipital lobe and lunate sulcus morphology resembling that of humans.
That the brain of H. naledi differs from that of Australopithecus is key. Discovered in 2013 within the Rising Star Cave system outside Johannesburg, South Africa, H. naledi is characterized as a curious mix of the Homo and Australopithecus genera. This analysis confirms that H. naledi was more similar to the early ancestors of modern humans, which were living in continental Africa at the same time. There’s not enough evidence to show whether they actually interacted with humans, but Gavin says “it’s always possible.”
Though their brains were more like ours than scientists first expected, it’s also difficult to determine whether their behavior was similar, too.
“There is a lot that we need to figure out even in regards to even our own brain and behaviors, so I think it’s a little early to make any concrete connections between H. naledi’s brain morphology and specific behavioral characteristics,” says Gavin. “That being said, the fact that H. naledi endocasts share features with other Homo species, features that are different from the Australopithecines, suggests that H. naledi likely exhibited more Homo-like behaviors.”
These behaviors are connected to the brain features highlighted in this paper. Their ubiquity in Homo brains, Gavin and her team write in the paper, “suggests a behavioral niche with serialized communication, planning, and complex action sequences that underlie tool production as well as an increased display of prosocial emotions.” The team hypothesizes that the increase in size of the hominin brain reflects an evolutionary adaptation to the structures demonstrated across Homo specimens. Our brains are a link to hominin cousins like the H. naledi, and in turn, to the first of our genus. Whether or not that initial Homo individual also had a small brain is another question that we can’t answer without more data from our family tree.
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13 отзывов о магазине
I enjoyed working with SkullMaskCraft to order this skull replica. Their response time was exceptional (especially given the time difference!), they were helpful and pleasant, and they were willing to work quickly and adjust the painted finish to my preference. Two caveats for other shoppers: The final product is what you see in the pictures-- the edges are a bit rounded and gaps (both large and small) filled in, so it wouldn't serve as an anatomically precise replica for study. (But contrast this with ordering what I would expect to be a more precise replica from Wits University in South Africa for 5x the cost.) Give yourself ample time to receive the order, as shipping times to other countries may be unreliable. Even after paying for expedited shipping, my order got stuck in a limbo of Russian customs and canceled flights.
Arrived today. A very good copy of the famous skull with REMOVABLE jaw! This producer is the ONLY one I'm aware of that makes fossil skull replicas that are economically attainable for the average person. I intend to order their entire line of hominid skulls in the coming year or two. VERY pleased.
Very satisfied with the skull models I purchased. The detail is good, (considering that they’re sourced from fossils that are hundreds of thousands of years old!) and they give interesting insight into how our ancient ancestors skulls differed from homo sapiens and from each other in skull anatomy and physiognomy. The material they’re made of is very sturdy. They were securely packaged in bubble wrap, and arrived un-damaged. Great customer service. Would definitely buy again.
Homo naledi had a tiny brain but it looked a lot like ours
The skulls of Homo naledi bear traces on their inside surfaces of the shape of naledi’s brain. Only a third the size of human brains, they nonetheless had some surprisingly human-like features. John Hawks, UW–Madison
In Africa, between 200,000 and 300,000 years ago, a small-brained human-like species called Homo naledi roamed the landscape alongside other early humans with larger brains, including those that may have ultimately become us — modern Homo sapiens.
Scientists and nonscientists have often associated larger brains with greater intelligence, but a new study published Monday (May 14, 2018) in the Proceedings of the National Academy of Sciences may challenge that notion. It shows that though its brain was small like those of apes and our more distant human ancestors, such as Australopithecus sediba, Homo naledi’s brain shared structural features (grooves and folds) decidedly more like humans.
“Maybe brain size isn’t all it’s cracked up to be,” says one of the study’s corresponding authors, John Hawks, a paleoanthropologist at the University of Wisconsin–Madison. “It opens the door for us to say that maybe they were more capable than we might assume maybe it isn’t just (brain) size.”
John Hawks is pictured at the Rising Star cave system in 2017. Photo: Jeff Miller
The study team used seven cranial, or skull, fragments from at least five individuals of Homo naledi found in 2013 in the Dinaledi Chamber of South Africa’s Rising Star Cave to develop a virtual three-dimensional model of part of the cranium. From these, they recreated the inside portion of the skull (an endocast) and were able to examine the imprints left behind by the brain.
This revealed information about the size and shape of individual parts of the brain, including features of the frontal lobe that are known to differ between apes, Australopithecus, and other Homo species, like Homo erectus and Neanderthals. Homo naledi’s brain was one-third the size of the modern human brain.
Hawks and study co-author Shawn Hurst, a graduate student at Indiana University Bloomington, presented some of the size and structure data at a meeting in April 2017, but the current study includes new comparative data that examines differences between Homo naledi and its Australopithecus cousins — sediba and africanus.
Homo naledi endocast (top) with a curvature map (bottom) highlighting the sulci that are visible. The frontal of naledi’s brain looked very human-like despite its small size. Heather Garvin, Des Moines University
In these cousins and in apes, a groove called the fronto-orbital sulcus is visible. In humans and other Homo species, this feature isn’t there, because two neighboring areas of the frontal lobe have expanded, partly covering over another area known as the insula. The best-preserved endocast from Homo naledi also lacks evidence of the fronto-orbital sulcus and mirrors the human form despite its small size.
A study published by another group last year showed that apes have more human-like brain features than scientists originally understood, but Hawks says the new study provides solid evidence that there are still differences in frontal lobe structures between apes and members of the genus Homo, including Homo naledi.
“When you look at human versus chimpanzee brains and their superficial similarities, it’s hard to identify these grooves in humans,” he explains. “But if you turn it to look at the bottom of the brain, you see they’re not similar at all. We’ve presented these images with the curvature highlighted to show this is actually where these grooves are and what the curvature is … When you look at this, there is no way to orient it in a way that’s equivalent to chimpanzees.”
The virtual models also suggest that Homo naledi may have had an asymmetrical brain. This is known as petalia, in which the two halves of the brain differ in size. For instance, the right frontal pole and left occipital lobe (in the back of the brain) are often larger and shifted forward and backward, respectively, in some right-handed people.
This asymmetry tends to be more pronounced in larger-brained Homo. However, while the scientists did not have enough fragments to fully assess asymmetry in Homo naledi’s brain, one fragment from the occipital region of the brain suggests it may also have shown human-like petalia.
“Maybe brain size isn’t all it’s cracked up to be.”
To complement the virtual models, Columbia University physical anthropologist Ralph Holloway, the study’s other corresponding author, created physical, latex-based endocasts of Homo naledi based on the scans the team took. Holloway has studied hominin brains for more than 50 years and, as Hawks explains, he has created “an incredible archive of endocasts across the fossil record.”
Before he built his models, Holloway did not believe the structures the virtual reconstructions described could possibly belong to a brain as small as Homo naledi’s, Hawks says.
“He said: ‘This looks very human-like to me and I have only seen this in bigger brains,” Hawks says. But Holloway’s physical models showed the same structural characteristics and were within five milliliters of the volume estimated from the virtual reconstructions.
The study shows that the more complex structural features of brains may not solely be a consequence of size, and it suggests that modern humans, Neanderthals and Homo naledi may have a common ancestor.
Evidence about the brain shape of Homo naledi comes from many partial skulls. The team used virtual methods to understand how naledi’s brain fits into the big picture. Heather Garvin, Des Moines University
“This is the smallest brain for which we have this clear evidence,” says Hawks. “Having big brains didn’t make our brains this way.”
The study cannot answer what these structures might have meant in terms of Homo naledi’s intelligence and behavior, though the features have been associated in other species with tool use, language and social behavior.
Homo naledi may have been burying its dead, a conclusion the research team reached after excavating a large assemblage of specimens from the Rising Star Cave, and it was contemporary with early humans who were making stone points and even using pigments. Or perhaps that was Homo naledi, too.
“What is brain size about?” Hawks ponders. “We don’t think we can conclude it means nothing or conclude we know much about (Homo) naledi’s function.”
For Hawks, the findings present even more questions about a time in human history where much still remains to be explored. “What do we say about Africa in the time that Homo naledi was there?” he asks. “What does it tell us about hominids and diversity and what it was about?”
He also says to stay tuned.
Other study authors include Heather Garvin from Des Moines University, P. Thomas Schoenemann from Indiana University Bloomington, William Vanti from Columbia University and Lee Berger from the University of the Witwatersrand.
The study was funded by the National Geographic Society, the National Research Foundation of South Africa, the Lyda Hill Foundation, the Fulbright Scholar Program, the Vilas Trust and the Wisconsin Alumni Research Foundation.
Homo naledi Had Small but Surprisingly Complex Brain
A species of extinct hominin called Homo naledi was discovered in 2013 in a remote cave chamber of the Rising Star cave system in South Africa. This species survived until 335,000-226,000 years ago, placing it in continental Africa at the same time as the early ancestors of anatomically modern humans were arising. According to new research, despite its small brain size, Homo naledi shared several aspects of structure in common with other species of the genus Homo (H. habilis, H. rudolfensis, H. floresiensis, and H. erectus), not found in other hominins or great apes, suggesting that innovations in brain structure were ancestral within our genus.
A reconstruction of Homo naledi’s head by paleoartist John Gurche. Image credit: John Gurche / Mark Thiessen / National Geographic.
An international team of paleoanthropologists from the University of Witwatersrand, Columbia University, and Indiana University pieced together traces of Homo naledi’s brain shape from an extraordinary collection of skull fragments and partial crania, from at least five adult individuals.
One of these bore a very clear imprint of the convolutions on the surface of the brain’s left frontal lobe.
“The anatomy of Homo naledi’s frontal lobe was similar to humans, and very different from great apes,” the scientists said.
“Other members of our genus, from Homo erectus to Homo habilis and the small-brained Homo floresiensis, also share features of the frontal lobe with living humans.”
But earlier human relatives, like Australopithecus africanus, had a much more apelike shape in this part of the brain, suggesting that functional changes in this brain region emerged within the genus Homo.
“It’s too soon to speculate about language or communication in Homo naledi, but today human language relies upon this brain region,” said co-author Dr. Shawn Hurst, a researcher in the Department of Anthropology at Indiana University.
“The back of the brain also showed humanlike changes in Homo naledi compared to more primitive hominins like Australopithecus.”
Human brains are usually asymmetrical, with the left brain displaced forward relative to the right.
The researchers found signs of this asymmetry in one of the most complete Homo naledi skull fragments.
They also found hints that the visual area of the brain, in the back of the cortex, was relatively smaller in Homo naledi than in chimpanzees — another humanlike trait.
Comparison of Homo naledi skulls to skulls of other hominin species. Image credit: Hawks et al, doi: 10.7554/eLife.24232.
The small brains of Homo naledi raise new questions about the evolution of human brain size.
Big brains were costly to human ancestors, and some species may have paid the costs with richer diets, hunting and gathering, and longer childhoods. But that scenario doesn’t seem to work well for Homo naledi, which had hands well-suited for tool-making, long legs, humanlike feet, and teeth suggesting a high-quality diet.
“Homo naledi’s brain seems like one you might predict for Homo habilis, 2 million years ago. But Homo habilis didn’t have such a tiny brain — Homo naledi did,” said co-author Dr. John Hawks, from the Evolutionary Studies Institute at the University of Witwatersrand.
A humanlike brain organization might mean that Homo naledi shared some behaviors with humans despite having a much smaller brain size.
“The recognition of Homo naledi’s small but complex brain will also have a significant impact on the study of African archaeology,” said co-author Professor Lee Berger, also from the Evolutionary Studies Institute at the University of Witwatersrand.
“Archaeologists have been too quick to assume that complex stone tool industries were made by modern humans. With Homo naledi being found in southern Africa, at the same time and place that the Middle Stone Age industry emerged, maybe we’ve had the story wrong the whole time.”
The research was published online this week in the Proceedings of the National Academy of Sciences.
Ralph L. Holloway et al. Endocast morphology of Homo naledi from the Dinaledi Chamber, South Africa. PNAS, publihsed online May 14, 2018 doi: 10.1073/pnas.1720842115
Video: Discovery of Homo naledi suggests ‘maybe brain size isn’t all it’s cracked up to be’ when it comes to human evolutionLee Berger with a replica of the skull of Homo naledi. Credit: Reuters/Siphiwe Sibeko
The small brains of Homo naledi raise new questions about the evolution of human brain size. Big brains were costly to human ancestors, and some species may have paid the costs with richer diets, hunting and gathering, and longer childhoods. But that scenario doesn’t seem to work well for Homo naledi, which had hands well-suited for toolmaking, long legs, humanlike feet, and teeth suggesting a high-quality diet.
According to study coauthor John Hawks, a paleoanthropologist at the University of Wisconsin–Madison. “Naledi’s brain seems like one you might predict for Homo habilis, two million years ago. But habilis didn’t have such a tiny brain–naledi did.”
“Maybe brain size isn’t all it’s cracked up to be,” said Hawks. “It opens the door for us to say that maybe they were more capable than we might assume maybe it isn’t just (brain) size.”
The research shows that the more complex structural features of brains may not solely be a consequence of size, and it suggests that modern humans, Neanderthals and Homo naledi may have a common ancestor.
One of the most remarkable archaeological finds of recent times was made in the fossil-rich area of the Gauteng Province, South Africa, known as the Cradle of Humankind. The find, first announced in November 2013, was made in a cave named Rising Star (Dinaledi in Sesotho, one of the local African languages) about 50 kms northwest of Johannesburg and about 16 kms from the Malapa cavewhere six skeletons of Australopithecus sediba were found in August 2008.
The fossils were found to have certain features in common with Homo sapiens and were thus announced to be a new species of the Homo genus, even possibly the very root of the Homo genus – and not Australopithecus. It was named Homo naledi (Star in Sesotho) after the cave in which the fossils were found. This declaration has been somewhat controversial, with some scientists believing instead that they are a branch of Homo erectus and not an entirely new species.
Two young cavers, Steven Tucker and Rick Hunter, while exploring the Dinaledi cave system initially found part of a jawbone and, after establishing that it was not the jawbone of an unlucky previous explorer, realised that they had found something noteworthy! While the opening areas of the cave have been well explored by local groups, the deeper aspects are extremely difficult to navigate, having two exceptionally narrow passageways (see Science’s diagram) and show no evidence of recent human visitation. The fossil site certainly was undisturbed. The first narrow passage is named Superman’s crawl because any wiry individual able to navigate it is only able to do so by keeping one arm firmly by their side and the other extended above their head, like Superman in flight! The second is approached by climbing the area known as Dragon’s back and in places is only 18 inches wide. It then drops steeply like an extremely narrow chute into the fossil site.
A small group from The Academy For Future Science, South Africa that went to view the display at Maropeng, the center established in Cradle of Humankind for the display of fossils and discoveries made in the area, was able to meet Rick Hunter (below) and get a firsthand description of their experience.
When Prof. Lee Berger of Wits University saw the photographs of what Tucker and Hunter had found, he sent out a call for ‘small’ scientists to explore the fossil site and obtained funding from National Geographic. Six brave women were selected to go into the fossil site and after painstaking work and exploration, Homo naledi was finally revealed to the world in September 2015 by the Rising Star expedition team.
From National Geographic October 2015
The question of how H. naledi came to be in the depths of Dinaledi cave has led to an intriguing theory. There is no indication on their fossilised bones of large carnivore activity and only very few rodent and bird skeletons have been found on the site, thus being dragged into the cave and eaten by a carnivore has been eliminated as a possibility. There is also no indication that the bones were carried to the site and deposited by water activity such as flooding. Therefore, after some determination the scientific team realized that the fossils had not ended up there because of some catastrophe but rather through a meticulous operation of several burials over a period of time.This has led them to the conclusion that H. naledi demonstrated the unusual characteristic of burying their dead and showing the trait of human compassion or ritual comprehension by the placing of their dead in a special chamber.
According to Drs. J.J. and Desiree Hurtak, “This new South African evidence gives credence to what The Keys of Enoch® (Key 207, Key 212) explain as the ‘root races,’ a pre-human life form similar to Homo sapiens sapiens but with a much smaller brain. The very concept of another species is not new. We already know that the Neanderthals (Homo neanderthalensis) and the Homo floresiensis lived on the earth, but this is the first evidence that an ancient species demonstrated the ritual of burying their dead.”
The remarkable find of Homo naledi is thus adding to the growing realization that there was more diversity in the evolution of species than ever imagined before, and that ritual behaviour and compassion for life may have been a much earlier development than was previously thought. It appears that this trait may not have developed exclusively in Homo sapiens.
While only a very small portion of this amazing time capsule with so many fossils found in the same area has been uncovered to date, the paleontological team has found intact skeletons (some 1,550 fossil elements in all) of every possible age, specifically they found the bones of infants, children, adults and an elderly individual believed to be female. There is a promise of more to come with at least one further major announcement expected soon.
Research to date indicates that on average Homo naledi was approximately 4 ½ft or 1.5 metres tall and weighed about 90 pounds (45kg). More recent work (March 2014) on one of the skeletons has confirmed the great similarity between the hands and feet of this ‘new species’ and modern man. The shoulders are narrower and more ape-like, more suited to climbing, but the feet are much closer to ours, and although their feet are flatter than ours, H. naledi were clearly bipedal (see images below – H. naledi foot on the right, ours on the left). However, their hip and thighbone seem much more primitive. While the hands and wrist are more human-like, possibly suited to making and using tools, they are a little different, that is the last digits of the hands are more curved, typical of primates, and again, suited to climbing. Also, the thumbs are longer.
H. naledi’s brain is said to have been the size of an orange, about half the size of Homo erectus and its skull has about half the brain volume of a modern human skull. However, its teeth were smaller than average for any early Homo species, a trait usually associated with eating more calorie-rich foods like meat or starchy tubers, according to John Hawkes, a core scientist on the Rising Star Expedition team.
Reconstructed composite skull of Homo naledi Jawbone of H. naledi by Wits University
While they have many features remarkably similar to Homo sapiens, they also display features that appear to be even more primitive than Australopithecus. Although specific dating has not entirely been confirmed, it is believed that this species lived one to three million years ago. If it turns out that they lived one million years ago or less then they would have co-existed with other early species of the Homo genus.
Photographs: Unless otherwise credited – by Peter Viljoen & Trish Roberson taken at Maropeng
Average Cranium/ Brain Size of Homo neanderthalensis vs. Homo sapiens
All humans on Earth are classified as Homo sapiens, also known as modern humans. This species of humans evolved 200,000 years ago. Initial theories presented evolution as a lineage where homo sapiens derived from Homo neanderthalensis who lived on earth from 250,000 to 30, 000 years ago. Recent studies have proven that Homo neanderthal and Homo sapiens existed at the same time with one another. In fact, evidence suggests that the advancement of Homo sapiens is accountable for the demise of Homo neanderthal. It is most likely, both species descended from Homo heidelbergensis who lived approximately 700,000 to 200,000 years ago and was the first of early humans to use fireand spears, and build shelters out of wood and rock.
While Homo heidelbergensis is the known ancestor of Homo neanderthal and Homo sapiens the evolution of modern humans dates back much farther. Prior to early humans it is has been known that humans have a relation to great apes which has been proven by genetic information. In the study of evolution, DNA is the most important component in being able to explore the difference between one species and another. While the genetic difference between individual humans today is minuscule – about 0.1%, on average – study of the same aspects of the chimpanzee genome indicates a difference of about 1.2%. The bonobo (Pan paniscus), the close cousin of chimpanzees (Pan troglodytes), differs from humans to the same degree. The DNA difference with gorillas, another African ape, is about 1.6%. Most importantly, chimpanzees, bonobos, and humans all show this same amount of difference from gorillas. A difference of 3.1% distinguishes us and the African apes from the Asian great ape, the orangutan (Smithsonian, National Museum of Natural History, 2015).
Humans belong to the biological group known as Primates, and are classified with the great apes, one of the major groups of the primate evolutionary tree. Besides similarities in anatomy and behavior, our close biological kinship with other primate species is indicated by DNA evidence. It confirms that our closest living biological relatives are chimpanzees and bonobos. But we did not evolve directly from any primates living today.DNA shows that our species and chimpanzees diverged from a common ancestor species that lived between 8 and 6 million years ago. The last common ancestor of monkeys and apes lived about 25 million years ago (Smithsonian, National Museum of Natural History, 2015).
Figure 1: Significant excavations of early and modern humans
Who is Homo neanderthalensis?
The name Homo neanderthalensis can be broken down with each word. Homo, is a Latin word meaning ‘human’ or ‘man’. Neanderthalensis is based on the location where the first major specimen was discovered in 1856, the Neander Valley in Germany. The German word for valley is ‘Tal’ although in the 1800s it was spelt ‘Thal’. Altogether Homo neanderthalensis therefore means ‘Human from the Neander Valley’. Hundreds of Neanderthal fossils have been found since the first identified in 1856 in the Neander Valley, Germany. Some defining features of the species include the large middle part of the face, angled cheekbones, and a huge nose for humidifying and warming cold, dry air. They had large brains and short, stocky physiques suited to living in cold environments. Their bodies were shorter and stockier than ours, another adaptation to living in cold environments. The average height of males was 5 ft. 5 in. (164 cm), weighing on average 143 lbs (65 kg). For females the average height was 5 ft. 1 in. (155 cm) and 119 lbs (54 kg) (Dorey, 2014).
Neanderthal bones are thick and heavy and show signs of powerful muscle attachments. Neanderthals most likely would have been extraordinarily strong by modern standards, and their skeletons show that they endured brutally hard lives. This species consisted of skilled hunter-gatherers, made and used flint and stone tools, built shelters and controlled fire. They were highly carnivorous, but they also ate other foods. There is limited evidence of plant food survival in the archaeological record. The number of plant foods Neanderthals could eat would have dropped significantly during the winter of colder climates, forcing Neanderthals to exploit other food options like meat more heavily. There is also evidence that Neanderthals were specialized seasonal hunters, eating animals were available at the time (i.e. reindeer in the winter and red deer in the summer). In Mediterranean regions, the Neanderthals exploited marine resources such as shellfish and seals, but their use of aquatic foods was certainly more limited than that of modern humans (Natural History Museum, 2015).
Neanderthals made and used a diverse set of sophisticated tools, controlled fire, lived in shelters, made and wore clothing, were skilled hunters of large animals and also ate plant foods, and occasionally made symbolic or ornamental objects. There is evidence that Neanderthals deliberately buried their dead and occasionally even marked their graves with offerings, such as flowers. No other primates, and no earlier human species, had ever practiced this sophisticated and symbolic behavior.
The Neanderthal genome project was founded in July 2006 by the Max Planck Institute Institute for Evolutionary Anthropology in Germany with the purpose of sequencing the Neanderthal genome. As previously mentioned, genetic data by this team suggest that Neanderthals shared a common ancestor with our species around 400,000 years ago, thought by many scientists to be Homo heidelbergensis. Neanderthals and modern humans belong to the same genus, Homo, and inhabited the same geographic areas in Asia for 30,000–50,000 years. Genetic evidence indicate while they may have interbred with non-African modern humans, they are separate branches of the human family tree (separate species). For about 70,000 years, Neanderthals roamed Earth with modern Homo sapiens. Fossil evidence from the Middle East suggests that our ancestors not only lived at the same time as Neanderthals, but probably lived alongside them in some areas. Results showed that people in Europe, Asia and New Guinea have around 2.5% Neanderthal DNA in their genetic code, suggesting Neanderthals interbred with modern humans not long after they spread out of Africa (Figure 1).
The “out of Africa” theory supports the idea that modern humans evolved relatively recently in Africa, migrated into Eurasia and replaced all populations which had descended from Homo erectus. The "out of Africa" hypothesis says that Neanderthals were no match for the better-adapted, quicker-witted Homo sapiens. They were out-competed, pushed out of their habitats, and ultimately driven to extinction by a superior species, Homo sapiens. Newly discovered evidence suggests another possibility, lending some credibility to a hypothesis that has languished in relative obscurity for as long as "out of Africa" has reigned. The "multiregional" hypothesis is the messy alternative. It says that pockets of Homo sapiens left Africa not in one large, unstoppable wave, but in smaller movements across many different regions. The hypothesis goes further to suggest that Neanderthals didn't actually go anywhere, but were instead subsumed into the various populations of Homo sapiens. This scenario implies that
Neanderthals were so closely related to Homo sapiens, a subspecies, that they interbred and mixed gene pools with our own. Yet another alternative theory suggests that Ice Age climate fluctuations affected European flora and fauna, causing the disappearance of familiar plants and animals, and that modern humans were better able to adapt than Neanderthals. With the reason for the disappearance unclear, one thing we are sure of is all physical evidence of the Neanderthals disappeared around 30,000 years ago (Brown, 2015).
Cranial/ Brain Size of Homo Neanderthalensis
Many people are under the misconception that Homo neanderthal had a smaller brain than modern humans since they were not as evolved. But their brains were just as large as ours and often larger, proportional to their brawnier bodies. Homo neanderthal brain size was larger than the average modern human brain and averaged 1500 cubic centimetres and an average 3.3 lbs. This is to be expected, as Neanderthals were generally heavier and more muscular than modern humans. People that live in cold climates also tend to have larger brains than those living in warm climates.
Homo neanderthal had a distinctive skull shape that was long and low, with a rounded braincase. The back of the skull had a bulge called the occipital bun and a depression (the suprainiac fossa) for the attachment of strong neck muscles. The skull was thick but rounded brow ridge lay under a relatively flat and receding forehead. Homo neanderthal possessed a mid-face region that showed a characteristic forward projection, this resulted in a face that looked like it had been ‘pulled’ forward by the nose. The orbits were large and rounded with a nose that was broad and very large (Australian Museum, 2015) (Figure 2).
Figure 2: Comparison of species to cranium configuration
Brain Function of Homo Neanderthalensis
Scientists have the fossilized skulls the Neanderthals left behind to decipher information about the brain and its function, which isn’t extremely helpful. Anthropologists now know that they used tools, made art, and may have talked. Still, nobody fully knows how their brains worked, or how their thinking was different from modern day humans. Fresh analysis of fossil data suggests that their brain structure was rather different. Although the brains of our ancestors and Neanderthals were about the same size, Neanderthals had larger brain areas related to vision and body control. Homo Neanderthalensis seem to have adopted an alternative strategy that involved enhanced vision coupled with retention of the physical robusticity of H. heidelbergensis, but not superior social cognition. Results imply that larger areas of the Neanderthal brain, compared to the modern human brain, were given over to vision and movement and this left less room for the higher level thinking required to form large social groups. For example, if the Neanderthals had less brain area devoted to social cognition, it might explain why they traveled shorter distances, had fewer symbolic artifacts and lived in smaller communities.
Smaller social groups is an aspect of Neanderthal explaining why Neanderthals went extinct whereas modern humans survived hence many theories surrounding this observation. Smaller social groups might have made Neanderthals less able to cope with the difficulties of their harsh Eurasian environments, because they would have had fewer friends to help them out in times of need (Fenlon, 2013).
Once the differences in body and visual system size are taken into account, researchers are able to compare how much of the brain was left over for other cognitive functions. Research by the Oxford scientists shows that modern humans living at higher latitudes evolved bigger vision areas in the brain to cope with the low light levels. This latest study builds on that research, suggesting that Neanderthals probably had larger eyes than contemporary humans because they evolved in Europe, whereas contemporary humans had only recently emerged from lower latitude Africa. Because this study is based on a hypothesis it is important to note certain regions are specialized to process certain types of sensory inputs and are active during certain tasks. But they’re all part of distributed functional networks, and we’re nowhere near understanding how those networks lead to this or that behavior. Scientists must always be careful about how to interpret any particular finding. In this case, the study shows a contrast between the visual systems of Neanderthals and our ancestors. That could underlie a difference in their social processing, or it could very well not (University of Oxford, 2015).
Who are Homo sapiens?
The name Homo sapiens, selected for ourselves means ‘wise human’. Homo is the Latin word for ‘human’ or ‘man’ and sapiens is derived from a Latin word that means ‘wise’ or ‘astute’. Homo sapiens is the name given to our species if we are considered a subspecies of a larger group. This name is used by those that describe the specimen from Herto, Ethiopia as Homo sapiens idàltuor by those who believed that modern humans and the Neanderthals were members of the same species. (The Neanderthals were called Homo sapiens neanderthalensis in this scheme). Homo sapiens evolved in Africa from Homo heidelbergensis. They co-existed for a long time in Europe and the Middle East with the Neanderthals, and possibly with Homo erectus in Asia and Homo floresiensis in Indonesia, but are now the only surviving human species. African fossils provide the best evidence for the evolutionary transition from Homo heidelbergensis to archaic Homo sapiens and then to early modern Homo sapiens. There is some difficulty in placing many of the transitional specimens into a particular species, because they have a mixture of intermediate features which are especially apparent in the sizes and shapes of the forehead, brow ridge and face. Some suggest the name Homo helmei for these intermediate specimens that represent populations on the brink of becoming modern. Late surviving populations of archaic Homo sapiens and Homo heidelbergensis lived alongside early modern Homo sapiens before disappearing from the fossil record by about 100,000 years ago (Australian Museum, 2015).
The earliest Homo sapiens had bodies with short, slender trunks and long limbs. These body proportions are an adaptation for surviving in tropical regions due to the greater proportion of skin surface available for cooling the body. More stocky builds gradually evolved when populations spread to cooler regions, as an adaptation that helped the body retain heat. Modern humans now have an average height of about 160 centimetres in females and 175 centimetres in males.
Cranial/ Brain Size of Homo Sapiens
Homo sapiens living today have an average brain size of about 1350 cubic centimetres which makes up 2.2% of our body weight making the brains of this species absolutely smaller than those of Homo neanderthalensis. However, due to its gracile postcranial skeleton, the brain of Homo sapiens is larger relative to body size than that of Homo neanderthalensis. Early Homo sapiens, however, had slightly larger brains at nearly 1500 cubic centimetres. The skulls of modern Homo sapiens have a short base and a high braincase. Unlike other species of Homo, the skull is broadest at the top and the sides of the skull are nearly vertical. The fuller braincase also results in almost no post-orbital constriction or narrowing behind the eye sockets. The back of the skull is rounded and indicates a reduction in neck muscles. The face of Homo sapiens is reasonably small with a projecting nose bone. They also have a limited brow ridge and the forehead is tall with orbits that are square rather than round. The skull of Homo sapiensgenerally lacks evidence of being strongly built (e.g., it lacks the large brow ridges and bony prominences seen in Homo neanderthalensis and Homo heidelbergensis) (Australian Museum, 2015) (Figure 3).
As early humans faced new environmental challenges and evolved bigger bodies, they evolved larger and more complex brains. Large, complex brains can process and store a lot of information. That was a big advantage to early humans in their social interactions and encounters with unfamiliar habitats. These unique features of Homo sapiens including changes in the skull and postcranial skeleton suggest changes in brain size and architecture and an adaptation to tropical environments. Over the course of human evolution, brain size tripled. The modern human brain is the largest and most complex of any living primate.
These anatomical changes are linked to cognitive and behavioral changes that are equally unique among hominin species. In particular, the archaeological evidence of behaviors thought to be unique to Homo sapiens, which appear first in Africa around 170,000 years ago, highlight the importance of symbolism, complex cognitive behaviors, and a broad subsistence strategy.
Even within the last 100,000 years, the long-term trends towards smaller molars and decreased robustness can be discerned. The face, jaw and teeth of Mesolithic humans (about 10,000 years ago) are about 10% more robust than ours. Upper Paleolithic humans (about 30,000 years ago) are about 20 to 30% more robust than the modern condition in Europe and Asia. These are considered modern humans, although they are sometimes termed "primitive". Interestingly, some modern humans (aboriginal Australians) have tooth sizes more typical of archaic sapiens. The smallest tooth sizes are found in those areas where food-processing techniques have been used for the longest time. This is a probable example of natural selection which has occurred within the last 10,000 years (Brace 1983).
Figure 3: The skull of Homo sapiens versus skull of Homo neanderthalensis