Middle Pleistocene Homo naledi

John Hawks discusses the latest news on the Rising Star Project:

Africa’s richest fossil hominin site has revealed more of its treasure. It’s been a year and a half since scientists announced that a new hominin species, which they called Homo naledi, had been discovered in the Rising Star Cave outside Johannesburg.

Now they say they have established and published the age of the original naledi fossils that garnered global headlines in 2015. Homo naledi lived sometime between 335 and 236 thousand years ago, making it relatively young.

They’ve also announced the discovery of a second chamber in the Rising Star cave system, which contained additional Homo naledi specimens. These include a child and the partial skeleton of an adult male with a well-preserved skull. They have named the skeleton “Neo” – a Sesotho word meaning “a gift”.

The Conversation Africa’s Science Editor Natasha Joseph asked Professor John Hawks, a member of the team, to explain the story behind these finds.

To an ordinary person, 236 000 years is a very long time ago. Why does the team suggest that in fact, Homo naledi is a “young” species?

The course of human evolution has taken the last seven million years since our ancestors diverged from those of chimpanzees and bonobos. The first two-thirds of that long history, called australopiths, were apelike creatures who developed the trick of walking upright on two legs.

Around two million years ago some varieties of hominins took the first real steps in a human direction. They’re the earliest clear members of our genus, Homo, and belong to species like Homo habilis, Homo erectus and Homo rudolfensis.

Homo naledi looks in many ways like these first members of Homo. It’s even more primitive than these species in many ways, and has a smaller brain than any of them. People outside our team who have studied the fossils mostly thought they should be around the same age. A few had the radical idea that H. naledi might have lived more recently, maybe around 900,000 years ago.

Nobody thought that these fossils could actually have come from the same recent time interval when modern humans were evolving, a mere 236 to 335 thousand years ago.

How do you figure out a fossil’s age?

We applied six different methods. The most valuable of these were electron spin resonance (ESR) dating, and uranium-thorium (U-Th) dating. ESR relies on the fact that teeth contain tiny crystals, and the electron energy in these crystals is affected by natural radiation in the ground over long periods of time after fossils are buried.

U-Th relies on the fact that water drips into caves and forms layers of calcite, which contain traces of uranium. The radioactive fraction of uranium decays into thorium slowly over time. So the proportion of thorium compared to uranium gives an estimate of the time since the calcite layers formed. One of these calcite deposits, called a flowstone, formed above the H. naledi fossils in the Dinaledi Chamber. That flowstone helps to establish the minimum age: the fossils must be older than the flowstone above them.

For these two methods, our team engaged two separate labs and asked them to process and analyse samples without talking to each other. Their processes produced the same results. This gives us great confidence that the results are reliable.

What does the discovery of Homo naledi’s age mean for our understanding of human history and evolution?

For at least the past 100 years, anthropologists have assumed that most of the evolution of Homo was a story of progress: brains got bigger over time, technology became more sophisticated and teeth got smaller as people relied more upon cleverness to get better food and prepare it by cooking.

We thought that once culture really got started, our evolution was driven by a feedback loop – better food allowed bigger brains, more clever adaptations, more sophisticated communication. That enabled better technology, which yielded more food, and so on like a snowball rolling downhill.

No other hominin species could compete with this human juggernaut. You would never see more than one form of human in a single part of the world, because the competition would be too intense. Other forms, like Neanderthals, existed within regions of the world apart from the mainstream leading to modern humans in Africa. But even they were basically human with large brains.

That thinking was wrong.

Africa south of the equator is the core of human evolutionary history. That’s where today’s human populations were most genetically diverse, and that diversity is just a small part of what once existed there. Different lineages of archaic humans once lived in this region. Anthropologists have found a few fossil remnants of these archaic populations. They’ve tried to connect those remnants in a straight line. But the genetic evidence suggests that they were much more complex, with deep divisions that occasionally intertwined.

H. naledi shows a lineage that existed for probably more than a million years, maybe two million years, from the time it branched from our family tree up to the last 300,000 years. During all this time, it lived in Africa with archaic lineages of humans, with the ancestors of modern humans, maybe with early modern humans themselves. It’s strikingly different from any of these other human forms, so primitive in many aspects. It represents a lost hominin community within which our species evolved.

I think we have to reexamine much of what we thought we knew about our shared evolutionary past in Africa. We know a lot of information from a few very tiny geographic areas. But the largest parts of the continent are unknown – they have no fossil record at all.

Explorers Mathabela Tsikoane, Maropeng Ramalepa, Dirk van Rooyen, Steven Tucker (seated), and Rick Hunter (seated) inside the Rising Star cave system. Wits University/Marina Elliott

We’re working to change that, and as our team and others make new discoveries, I’m pretty sure we are going to find more lineages that have been hidden to us. H. naledi will not be the last.

The first Homo naledi discoveries were made in the Dinaledi Chamber. What led researchers to the second chamber? And what did you find there?

The Dinaledi Chamber is one of the most significant fossil finds in history. After excavating only a very tiny part of this chamber, the sample of hominin specimens is already larger than any other single assemblage in Africa.

The explorers who first found these bones, Rick Hunter and Steven Tucker, saw what the team was doing when they were excavating in the chamber. The pair realised that they might have seen a similar occurrence in another part of the cave system. The Rising Star system has more than two kilometres of mapped passages underground. In another deep chamber, accessed again through very tight underground squeezes, there were hominin bones exposed on the surface.

Our team first began systematic survey of this chamber, which we named the Lesedi Chamber, in 2014. For two years Marina Elliott led excavations, joined at times by most of the team’s other experienced underground excavators. They were working in a situation where bones are jammed into a tight blind tunnel. Only one excavator can fit at a time, belly-down, feet sticking out. It is an incredibly challenging excavation circumstance.

Geologist Dr Hannah Hilbert-Wolf studying difficult to reach flowstones in a small side passage in the Dinaledi Chamber. Wits University

The most significant discovery is a partial skeleton of H. naledi, with parts of the arms, legs, a lot of the spine and many other pieces, as well as a beautifully complete skull and jaw. We named this skeleton “Neo”. We also recovered fragments of at least one other adult individual, and one child, although we suspect these bones may come from one or two more individuals.

Is there a way for people to view these discoveries in person?

On May 25 – Africa DayMaropeng at the Cradle of Humankind World Heritage Site outside Johannesburg will open a new exhibit with the discoveries from the Lesedi Chamber and the Dinaledi Chamber together for the first time.

For people outside South Africa, the data from our three-dimensional scans of the new Lesedi fossils are available online.

Anyone can download the 3D models, and people with access to a 3D printer can print their own physical copies of the new fossils, as well as the fossils from the Dinaledi Chamber. It’s a great way for people to see the evidence for themselves.

Reprint from The Conversation

Three reasons the Cerutti Mastodon was not manipulated by hominins

A team of scientists recently announced an extraordinary claim that the 130,000 Cerutti Mastodon was manipulated by hominins.

“I have read that paper and I was astonished by it,” archaeologist Donald Grayson of the University of Washington. “I was astonished not because it is so good, but because it is so bad. Cracked bones and chipped stones at a fossil site might mean anything”, said Grayson. “It is quite another thing to show that people, and people alone, could have produced those modifications. The study doesn’t take that step, he said, “making this a very easy claim to dismiss.”

Gary Haynes of the University of Nevada Reno had this to say, “The paper states that the bones were being exposed by a backhoe. These pieces of heavy equipment weigh seven to fifteen tons or more, and their weight on the sediments would have crushed bones and rocks against each other.” When asked, Holen, the study leader, said that it “was very easy to tell the difference” between fractures made by stone hammers and those seen in bones crushed by bulldozers. He did not elaborate on how the differences manifest. “He’s pretty much dead wrong — there’s no definable difference,” Haynes said. A similar fossil dispute broke out in 2015 over a 24,000 year old mammoth in Maryland, he noted, shown to be fractured by heavy equipment. Also troubling, the “hammer” and “anvil” stones described in the paper don’t unequivocally look like tools, said Michael Waters of Texas A&M’s Center for the Study of the First Americans.

Michael Waters of Texas A&M’s Center for the Study of the First Americans noted that the “hammer” and “anvil” stones described in the paper don’t unequivocally look like tools. The study also runs afoul of the mounting genetic evidence, which indicates that the first people to reach the Americas and eventually give rise to modern Native Americans arrived no earlier than 25,000 years ago.”

1.6 Million Year Old Woman of Eastern Africa (2017 Review)

When fossil hunter Bernard Ngeneo came across the remains of this fossil, only the upper portion of the orbits were protruding from the ground. Excavation revealed one of the best preserved skulls of this time period, and one of the most striking early human fossils of any age.

KNM-ER 3733 represents a mature female of the early human species Homo erectus. The sex identification comes from a comparison of the anatomical features of her face with several other crania from Koobi Fora: KNM-ER 3883 (male), and KNM-WT 15000 (also male), found on the opposite side of Lake Turkana. The features of KNM-ER 3733 are markedly less robust. It’s known to be an adult on the basis of the cranial sutures (which were fully closed), the extent of the wear on the teeth, and the eruption of the third molars before the individual’s death.

How forensic science can unlock the mysteries of human evolution

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People are fascinated by the use of forensic science to solve crimes. Any science can be forensic when used in the criminal and civil justice system – biology, genetics and chemistry have been applied in this way. Now something rather special is happening: the scientific skill sets developed while investigating crime scenes, homicides and mass fatalities are being put to use outside the courtroom. Forensic anthropology is one field where this is happening.

Loosely defined, forensic anthropology is the analysis of human remains for the purpose of establishing identity in both living and dead individuals. In the case of the dead this often focuses on analyses of the skeleton. But any and all parts of the physical body can be analysed. The forensic anthropologist is an expert at assessing biological sex, age at death, living height and ancestral affinity from the skeleton.

Our newest research has extended forensic science’s reach from the present into prehistory. In the study, published in the Journal of Archaeological Science, we applied common forensic anthropology techniques to investigate the biological sex of artists who lived long before the invention of the written word.

We specifically focused on those who produced a type of art known as a hand stencil. We applied forensic biometrics to produce statistically robust results which, we hope, will offset some of the problems archaeological researchers have encountered in dealing with this ancient art form.

Sexing rock art

Ancient hand stencils were made by blowing, spitting or stippling pigment onto a hand while it was held against a rock surface. This left a negative impression on the rock in the shape of the hand.

Experimental production of a hand stencil. Jason Hall, University of Liverpool

These stencils are frequently found alongside pictorial cave art created during a period known as the Upper Palaeolithic, which started roughly 40 000 years ago.

Archaeologists have long been interested in such art. The presence of a human hand creates a direct, physical connection with an artist who lived millennia ago. Archaeologists have often focused on who made the art – not the individual’s identity, but whether the artist was male or female.

Until now, researchers have focused on studying hand size and finger length to address the artist’s sex. The size and shape of the hand is influenced by biological sex as sex hormones determine the relative length of fingers during development, known as 2D:4D ratios.

But many ratio-based studies applied to rock art have generally been difficult to replicate. They’ve often produced conflicting results. The problem with focusing on hand size and finger length is that two differently shaped hands can have identical linear dimensions and ratios.

To overcome this we adopted an approach based on forensic biometric principles. This promises to be both more statistically robust and more open to replication between researchers in different parts of the world.

The study used a branch of statistics called Geometric Morphometric Methods. The underpinnings of this discipline date back to the early 20th century. More recently computing and digital technology have allowed scientists to capture objects in 2D and 3D before extracting shape and size differences within a common spatial framework.

In our study we used experimentally produced stencils from 132 volunteers. The stencils were digitised and 19 anatomical landmarks were applied to each image. These correspond to features on the fingers and palms which are the same between individuals, as depicted in figure 2. This produced a matrix of x-y coordinates of each hand, which represented the shape of each hand as the equivalent of a map reference system.

Figure 2. Geometric morphometric landmarks applied to an experimentally produced hand stencil. This shows the 19 geometric landmarks applied to a hand. Emma Nelson, University of Liverpool

We used a technique called Procrustes superimposition to move and translate each hand outline into the same spatial framework and scale them against each other. This made the difference between individuals and sexes objectively apparent.

Procrustes also allowed us to treat shape and size as discrete entities, analysing them either independently or together. Then we applied discriminant statistics to investigate which component of hand form could best be used to assess whether an outline was from a male or a female. After discrimination we were able to predict the sex of the hand in 83% of cases using a size proxy, but with over 90% accuracy when size and shape of the hand were combined.

An analysis called Partial Least Squares was used to treat the hand as discrete anatomical units; that is, palm and fingers independently. Rather surprisingly the shape of the palm was a much better indicator of the sex of the hand than the fingers. This goes counter to received wisdom.

This would allow us to predict sex in hand stencils which have missing digits – a common issue in Palaeolithic rock art – where whole or part fingers are often missing or obscured.

Palaeo-forensics

This study adds to the body of research that has already used forensic science to understand prehistory. Beyond rock art, forensic anthropology is helping to develop the emergent field of palaeo-forensics: the application of forensic analyses into the deep past.

For instance, we have been able to understand fatal falls in Australopithecus sediba from Malapa and primitive mortuary practices in the species Homo naledi from Rising Star Cave, both in South Africa.

All of this shows the synergy that arises when the palaeo, archaeological and forensic sciences are brought together to advance humans’ understanding of the past.

The above article was reprinted from The Conversation

The Siberian and the Laika Hunting Dog

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Recently, I came across this early photograph of unknown origin. Confusion abounds online as to the origin and story behind it. After some time spent researching I ended up uncovering a dark past of Tsarist Russia. Siberia remained untouched by the outside world for many centuries, but that changed when the Ivan IV Vasilyevich (1530 – 1584) initiated a colonisation of Siberia beginning in July of 1580. This had disasterous concequences for the indigenous people who did not take to kindly to this subjugation. From 1706 to 1741, a series of Itelmen rebellions were brutally crushed, while the Koryak Rebellions of 1745 – 1756 marked a truly dark and bloody time in Siberian history. By about 1882, 12 indigenous groups were exterminated by the Russian Cossacks.

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Yermak’s Conquest of Siberia (1895) – Vasiliy Surikov

In the midst of all this chaos, groups of ethnographers were making there way into these territories to record and document the way of life and the diverse languages of Siberia. We have four very important people to thank for this. Waldemar (Vladimir) I. Jochelson (1855-1937) and Waldemar (Vladimir) G. Bogoras (1865-1936) published many articles on the way of life of the Siberian peoples, as part of the famous Jesup Expedition . Waldemar Jochelson and his wife Dina Brodskaya, lived among the Koryak, Yukaghir, and Sakha (Yakut) peoples for nearly two years. Dina’s primary task was to prepare medical records and photograph life in Siberian, while she could do little to address the outbreak of measles. The Koryak people had abandoned their camp along the river Gizhiga to retreat up into the mountains with the reindeer. They suffered a 25% death rate thanks to the measles outbreak. Waldemar Bogaras and his wife Sofia lived with the Chukchee people who by 1900 had suffered a 30% drop in population thanks to the measles outbreak.

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River Gizhiga

And this brings me to the second consequence of warfare between the Russian Co
ssacks and the indigenous Siberian people – epidemic outbreak. The Siberian population was decimated by measles and smallpox outbreaks over the three hundred years of warfare. It was Waldemar who documented the languages and folklore of the Chukchee.

It is likely that Dina Brodskaya took the photograph of the Yukaghir adult and the Laika hunting dog in the autumn of 1900. I cannot imagine the frustration of the team in carrying the heavy photographic equipment across the inhospitable siberian wilderness.

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Major groups of eastern Siberia

The First Human Epidemic: Late Pleistocene Origin?

Current models of infectious disease in the Pleistocene tell us little about the pathogens that would have infected Neanderthals (Homo neanderthalensis). High quality Altai Neanderthal and Denisovan genomes are revealing which regions of archaic hominin DNA have persisted in the modern human genome. A number of these regions are associated with response to infection and immunity, with a suggestion that derived Neanderthal alleles found in modern Europeans and East Asians may be associated with autoimmunity. Independent sources of DNA-based evidence allow a re-evaluation of the nature and timing of the first epidemiologic transition. The paradigm of the first epidemiologic transmission, the hypothesis that epidemic disease did not occur until the transition to agriculture, with larger, denser and more sedentary populations, has been essentially unchallenged since the 1970s. Our views of the infectious disease environment of the Pleistocene period are heavily influenced by skeletal data and studies of contemporary hunter-gatherers. New genetic data – encompassing both hosts and pathogens – has the power to transform our view of the infectious disease landscape experienced by Neanderthals in Europe, and the anatomically modern humans (AMH) with whom they came into contact. The Pleistocene hominin environment cannot be thought of as free from infectious disease. It seems likely that the first epidemiologic transition, envisaged as part of the package of the Holocene farming lifestyle, may be fundamentally different in pace or scope than has previously been suggested. This paper demonstrates how high quality genomic data sets can be used to address questions arisingfrom the ecological context that shaped the co-evolutionary relationship we share with infectious diseases. We analyse the evidence for infectious disease in Neanderthals, beginning with that of infection-related skeletal pathologies in the archaeological record, and then consider the role of infection in hominin evolution. We have synthesised current models on the chronology of emergence of notable European disease packages and analyse what implications this evidence has for the classical model of the first epidemiologic transition. Using emerging data from Neanderthal palaeogenomics and combining this with fossil and archaeological information we re-examine the impact of infectious diseases on human populations from an evolutionary context. These palaeogeneticists argue that the first epidemiologic transition in Eurasia was not as tightly tied to the onset of the Holocene as has previously been assumed. There is clear evidence to suggest that this transition began before the appearance of agriculture and occurred over a timescale of tens of thousands of years. We suggest that the epidemiological transition was not, as has been thought since the 1970s, a phenomenon of the human shift to sedentary agriculture during the Holocene but a much older and more complex process that involved at least two species of humans. The origin of resistance to infectious disease has a much deeper timeframe and is highlighted by the ingression of Neanderthal DNA into modern human lineages. The transfer of pathogens between human species may also have played a role in the extinction of the Neanderthals. Our analysis of the genomes of archaic hominins provides evidence of pathogens acting as a population-level selection pressure, causing changes in genomes that were passed on to descendants and preserved in the genomes of modern Eurasians. the analysis of ancient genomes demonstrates that human behavioural patterns (in this case a shift to agricultural subsistence) should not be used as an ecological proxy to explain shifting trends in the co-evolutionary relationship between pathogens and human populations.

This work is available on BioRxiv: http://dx.doi.org/10.1101/017343

Acknowledgements: Rob Foley, Marta Lahr and the members of the Human Evolutionary Science Discussion Group at the University
of Cambridge. Funding for this research was provided by King’s College Cambridge and UCL.

Meganthropus palaeojavanicus – The Early Years of Palaeoanthropological Research (1942 – 1955)

Meganthropus palaeojavanicus (from the Ancient Greek, meaning Ancient Java’s Great Human) is a redundant genus and species that was first formally introduced by Gustav vonKoenigswald (1902 – 1982) in 1950. The genus once referred to a set of fossils found on the island of Java in the 1930’s, 1940’s, 1950’s and 1980’s. The Javan fossils are now attributed to the hominin Homo erectus that lived from 1.9 million years ago to 300,000 years ago and had a range from Africa to Eurasia.

vonKoenigswald’s Meganthropus palaeojavanicus

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Gustav Heinrich Ralph vonKoenigswald (1902 – 1982)

On the 15th of January 1942, the Director of the Geological Survey of the Netherlands Indies, W. C. B. Koolhoven wrote a letter to anatomist and palaeoanthropologist, Franz Weidenreich informing him that vonKoenigswald wishes the 1939 and 1941 to be attributed to a new genus and species of ape called M. palaeojavanicus. In 1945, Weidenreich referred to it as “vonKoenigswald’s Meganthropus palaeojavanicus”. Held in the Senckenberg Forschungsinstitute und Naturmuseum, an unpublished 1949 scientific paper written by vonKoenigswald proposes that Sangiran 1a,  It was not until 1950, the vonKoenigswald committed his new genus and species to print in a formal introduction. As the sixth decade of the 20th century developed, consensus shifted towards H. erectus as the taxonomic appellation of the Javan fossils.

“Meganthropus” Fossils

The following are a list of fossils that were taxonomically assigned to Meganthropus, but have now been officially assigned to H. erectus

Franz Weidenreich
Franz Weidenreich (1873 – 1948)

Sangiran 6a

Kromopawiro (a team member) discovered the fossil adult mandible fragment “near Glagahombo, north of Sangiran” not far from where another cranium was uncovered in 1939 and south of Sangiran 4’s location. Weidenreich described the 1.6 million year old fossil in 1945, in which he pointed out the size of the mandible and the primitive premolar morphology as evidence to support the application of a new genus and species – M. palaeojavanicus. This conclusion was revised in 1989, when Kramer concluded that the size was within the size range of H. erectus.

Sangiran 7

Dating to between 1.51 and 1.6 million years of age, Sangiran 7 (comprising 54 teeth) was recovered from 1937 to 1941. Fred Grine analysed some of the teeth in 1984, but it would be a decade later before he revised his earlier conclusion that they were hominin. As a result, three teeth FS 67, 72 and 83 were re-attributed to Pongo sp.

Wilfrid Le Gros Clark (1895 – 1971)

Sangiran 8

Uncovered in 1952, Sangiran 8 comprises fragment of mandible, with some teeth roots intact and a complete third molar crown. This individual is interpreted to have died in the jaws of a crocodile, based upon the scare marks on the fossil. The fossil was first described in 1953 by P. Marks concluding it lay outside the size range of H. erectus. In 1955, Le Gros Clark concluded that the fossil was within the range of H. erectus and that has remained the official attribution for Sangiran 8 ever since.

Sangiran 27

This partial adult cranium was first found in 1978 near Sangiran village, north of the River Chemoro and it was found as construction was underway on a new dam. The skull was found in the upper levels of the Sangiran Formation dating to between 1.66 and 1.58 million years of age. The fossil was described by Teuku Jacob in 1980, in which he attributed it to Meganthropus but was taxonomically revised in 2008 for reasons similar to the taxonomic revision of Sangiran 8. Indriati and Anton (2008) also noted that hyper-robust features of the fossil reflects earlier representatives of H. erectus.

Modern Uses of Meganthropus

Though taxonomically and scientifically redundant, Meganthropus is used by pseudoscientific Creationists as evidence for the Nephilim, giants that lived before Noah’s flood, referenced from an Iron Age manuscript called the “Book of Enoch”.

Norandino and Lucina Discovered by the Ogre (1624) – Giovanni Lanfranco (1582 – 1647)

A trickle of scientific papers and posters have been published and presented over the decades, claiming evidence for Meganthropus. Authors have suggest that Sangiran 5 is evidence of the existence of an older, “more robust morph”, with pongo-like characteristics. Suggesting that a Gigantopithecus-like counterpart lived in island South-East Asia. The most recent appearance of support for Meganthropus was at the 83rd annual meeting of the American Association of Physical Anthropologists in 2014, a team of scientists led by Clement Zanolli presented a poster on their analysis of a fossil mandible fragment code named Arjuna 9. They suggested that teeth had enamel thickness and dental tissue proportions that differed from those seen in H. erectus. The statistical analysis of the enamel-dentine junction also seemed to support an attribution to Pongo sp. The fact remains, no evidence exists to support classifying the Javan fossils as Meganthropus.

Gorjanović-Kramberger Hypothesis: Took 99 Years, But We Finally Tested It

You meet Homo neanderthalensis in a dark alley……………….What do you do?

Homo neanderthalensis is one of the best understood species of hominin today. One that lasted many hundreds of thousands of years throughout Europe. Despite what we know through the lens of science, there is still much that we want to know about this species of human. Interrogating the subtle pieces of evidence is the task of palaeoanthropologists, archaeologists, palaeoenvironmental scientists throughout the world. Contrary to what you may see on your average human evolution documentary, the kind of research conducted can be much more subtle. Here I will draw your attention to a difficult question. If we could fill the Great Hall of the South Kensington Museum with a few hundred individuals of our extinct cousin, what differences would we see in the upper chest and neck. The answer to that, at the beginning of 2015: We are not happy that we really know enough to give an answer.

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Range of Homo neanderthalensis

H. neanderthalensis is a well represented species of human in the fossil record, but the post-cranial anatomy is less well accounted for than the skulls. Not ideal for an investigation into the chest and abdominal regions of the human body. Nevertheless, it is vital we exhaustively examine what we have, to reveal potential clues to the kind of morphology these populations once exhibited. To that end, ten palaeobiologists from various Spanish academic institutions presented evidence that may be useful here. The mechanics of the breathing system, constrained by the rib cage and not the evolution of the species, is the focus here. Research continues to be a work in progress, new technologies arrive and they help further our understanding of the past. This research is no exception. Two year into the new millennium a new form of analysis that gauged quantity within a structure was applied to a collection of isolated ribs from an individual codenamed Shanidar 3. This individual had a more splayed lower rib cage compared to the more barrel-like form of our lower rib cage. Thus started a series of papers that suggested the lower rib cage of Homo neanderthalensis was generally less like ours. Comparatively less investigative research has been given to the upper end of the rib cage. This latest academic paper sets out to help understand just that.

Title and Authors of the Paper in Question
Title and Authors of the Paper in Question
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Dragutin Gorjanović-Kramberger (1856 – 1936)

In 1906 and a time when ancient humans were Anti or Post Diluvian Era (Noah’s Great Flood), Dragutin Gorjanović-Kramberger suggested that the superior ribs are an important facet of an upper thoracic orchestra of components, that together control upper thoracic breathing, separate from diaphragmatic breathing. It was not until 2015 that this hypothesis was put to the test on six hominin first-ribs from the cave site of El Sidrón, Asturias, northern Spain. The six first-rib fragments may represent, at most, four individuals. The first step was to identify the bone fragments and place them in their correct anatomical position. Below is a re-organisation of the information given about the sample itself. The first-rib of Kebara 2 was found to be similar in shape space and form space (both terms used in a statistical analysis of shape, known as Procrustes Least Squares (PLS)) to SD-1767 and SD-1699, indeed H. neanderthalensis exhibits straighter first-ribs than modern day Homo sapiens. What could this mean? The scalene muscles are the ones that give your neck, its shape. They run from the Rib 1 and Rib 2 up the side of your neck attaching to the vertebrae. Alteration in shape of the first ribs, and the attached muscles will have to operate differently, but may help explain the differences we see between H. sapiens and H. neanderthalensis. The principle component analysis (PCA) reveals some overlap in the linearity of the rib shaft. Such results are reflected in analysis of the specimens of Krapina Cave, Croatia and ATD6-108 representing Homo antecessor, from Gran Dolina Cave, Atapuerca, Spain. So, the straightness of the first-ribs may affect the movement of the upper torso during breathing.

Juvenile 1: SD-2148 (Right) and SD-2172 (Left)

Juvenile 2: SD-417 (Left) and SD-1225 (Right)

Large Adolescent / Small Adult: SD-1767 (Left)

Large Adult: SD-1699 (Right)

Looking at the juveniles, it is important to understand costal cartilage development. Understanding adult H. neanderthalensis individuals is easier, as there are more post-cranial fossils, but the El Sidrón hominins will be useful in understanding the ontogeny of costal cartilage in future fossil ribs of  juveniles. The El Sidrón juveniles confirm a tighter upper chest for H. neanderthalensis. The first-ribs are smaller, but feature larger attachments at the rib heads, whereas the lower ribs have smaller attachment points. Therefore, a H. neanderthalensis individual, exhibited a smaller upper torso, which was further from the cranium thanks to the slightly longer neck vertebrae. First-ribs that are straighter would have to project out from the skeleton more and Gorjanović-Kramberger proposed that the rest of the rib-cage would project outward, just as much. The scientific team added to this, that a change in the first ribs would in turn affect the rest of the rib-cage, because the ribs are latched together with intercostal muscle, preventing individual ribs from varying in shape, that ultimately allows coordination of muscle, chest wall and breathing action. Upper ribs connect directly with the sternum and so, result in distinctive rib shape compared with the lower thorax.

Association of Intercostal Muscle and Rib Bone
Association of Intercostal Muscle and Rib Bone

To summarise, the first ribs appear to determine the shape of the upper thorax ribs, but straightness of the first rib is linked with the straightness of the upper ribs. Together, this suggests the existence of different rib shape and functions between the upper and lower thorax. When you look at a particular fossil specimen, it is important you are aware of what bones, muscles, cartilage was associated with it. They all interact in subtle ways which we are piecing together in hominins, with the variety in body forms available going back 7 million years. In examination of the monophyly of Paranthropus, cladistical statistics showed us that the skeletal points used, should not be linked with eachother. An example of that, would be the masticatory system in Paranthropus comprising numerous points, all interacting with one another. This is a shame because the crania and mandibles are predominantly all we have of that genus. Currently, most are happy that Paranthropus boisei, Paranthropus aethiopicus and Paranthropus robustus are part of the same family – they are monophyletic. The rib cage, is similar to the masticatory system but it is a single unit with two functions, one  is upper thoracic respiration and the other is diaphragmatic respiration. H. neanderthalensis evolved a more restrictive respiratory system and highly developed arm muscles, evolutionarily more important for the condition in which it lived. So, if you were to meet our ancient ancestor in a dark alley, what should you do? It would have been prone to breathlessness, but could rearrange your face easier. Moral of the story, RUN!

The costal remains of the El Sidrón Neanderthal site (Asturias, northern Spain) and their importance for understanding Neanderthal thorax morphology

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Descent of Palaeoanthropology on Florence 18th – 20th of September 2014

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Human Evolutionary research has come a long way since Darwin’s ‘Descent of Man and selection in relation to Sex’ in 1871. It has matured and developed into a respectable discipline. Less and less do we see personal egos influence research and conclusions, more and more do we see a worldwide interest in researching our hominin past, not just in the USA. A number of years ago, the European Society of the study of Human Evolution was established as an answer to the American conferences. This conference type is long overdue in Europe for those who don’t have the time or finances to travel to the US. I have been to the 2013 conference which was held in Vienna. My time there was nothing short of enjoyable. Loving every moment from cruising down the Danube to lectures on the carcass processing by Homo erectus in eastern Africa.

Now I have this conference to look forward to, taking place in the town of Florence, northern Italy. What follows are a few of what I consider highlights of the visit.

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 Cover Page of the Abstracts booklet with details of the excursion: Check it out Here

The Keynote will be given by Professor Guido Barbujani (pictured below) of the Department of Life Sciences and Biotechnologies of the University of Vienna. Here he will give us an overview of an aspect of linguistics research – comparing distantly related languages. Traditionally, comparisons were focused upon the lexial. When it came to languages with quite different vocabulary, the lexial comparison experienced numerous difficulties. The Parametric Comparative Method (PCM) of syntax and grammar appears to go beyond the difficulties found in lexial comparisons. What’s more, it is a much better predictor of differences found in the human genome, than that shown by geographical comparisons. I know little about linguistics, but on the face of it, this does sound promising. Based on what I know, linguistics has been nothing but conjecture, rather like most of theorical physics. It is the experimental physicists that have to help them test their hypotheses. Cross-disciplinary work is much better than going it alone, history reveals this to us. Today there is much communication going on between disciplines, working together bringing the skills and techniques of each discipline to the table to help unravel the mystery of the world.

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My masters research involved the investigation of Paranthropean biogeography between eastern Africa and southern Africa. So, it will be no surprise to my friends and colleagues, that I will be particularly interest in the poster presentation by Andrew Gallagher, entitled Size and Sex variance in Paranthropus robustus: Taxonomic and Palaeobiological implications. Another poster presentation, I will be very interested in viewing is also shown during Poster Session 1 and that’s the one by Sandrine Prat entitled A specimen of Paranthropus robustus from Bolt’s Farm Cave system, Cradle of Humankind, South Africa.

What excites me most about this conference is the nomadic activity it indulges in from year to year. Most conferences in any discipline are like this anyway, but I want to emphasise here, because I get to see a part of Italy few tourists get to see or for that matter want to see. The words you see here on this post can never fully explain the childish excitement I’m experiencing here, in the Member’s Room in the British Museum.

Another highlight will be our visit to a spa resort to relax and bathe in the wonder and awe of palaeolithic cave archaeology. See what I did there! The Cave of the Fair Spa or Grotte di Equ080406_burren8i Terme in summary is a Mousterian Heaven. Being tectonically porous, sulphurous hot springs seep up from the earth below and since the Romans couldn’t get enough of hot springs, this area became a very popular resort to kick back and chill. Though I doubt the Romans knew what treasures lay at the back of nearby caves. Like the famed limestone landscape of the Burren in the West of Ireland (Above), this area is karstic.

Karst = Caves = Archaeological & Zooarchaeological Remains

Now that I think of it, would it not be interesting to discuss prehistoric use of hot springs. Let’s try to attempt to reconstruct an extended family of Homo neanderthalensis availing of the springs. Would these springs have been in demand? If yes, then was competition fierce among Homo sapiens and Homo neanderthalensis for this location, especially during the winter months. Who knows? But its a fun idea to play around with, don’t you think?

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 Equi Terme Hamlet

So I’m excited because I love discovery. It inspires me, makes me feel positive and I feel a sense of humility, knowing how far humanity has come since Homo ergaster left Africa a million and a half years ago. That’s fine, but there is alot of work needed to help us understand the past. My expertise lies in Archaeology and so I’m particularly interested in the stone tools that were deposited in these caves. Dating to Marine Isotope Stage 3 (MIS 3) from about 57,000 to 29,000 years ago, numerous excavations were undertaken at the caves in the decade of World War I. In July of 2014 a paper was published by Ghezzo et al, entitled Recovering data from historical collections: stratigraphic and spatial reconstruction of the outstanding carnivoran record from the Late Pleistocene Equi Cave (Apuane Alps, Italy), seeking to merge modern data with that of the early 20th century antiquarians. The zooarchaeological record of the Cave of the Fair Spa is one of the richest in northern Italy, but it also contains a lithic assemblage sometimes referred to as the Alpine Mousterian. So, its Mousterian with a twist (not literally, of course).

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Rio Secco Cave, north-eastern Italy – Mousterian Assemblage