Did Lead Limit Brain and Language Development in Neanderthals and Other Extinct Hominids?

UC San Diego researchers have found high levels of lead in the teeth of both Neanderthals (left) and modern humans (right). However, a gene mutation may have protected modern human brains, allowing language to flourish.
Photo Credit: Kyle Dykes/UC San Diego Health Sciences

Ancient human relatives were exposed to lead up to two million years ago, according to a new study. However, a gene mutation may have protected modern human brains, allowing language to flourish.

What set the modern human brain apart from our now extinct relatives like Neanderthals? A new study by University of California San Diego School of Medicine and an international team of researchers reveals that ancient hominids — including early humans and great apes — were exposed to lead earlier than previously thought, up to two million years before modern humans began mining the metal. This exposure may have shaped the evolution of hominid brains, limiting language and social development in all but modern humans due to a protective genetic variant that only we carry. The study was published in Science Advances.

The researchers analyzed fossilized teeth from 51 hominids across Africa, Asia and Europe, including modern and archaic humans such as Neanderthals, ancient human ancestors like Australopithecus africanus, and extinct great apes such as Gigantopithecus blacki.

Easter Island’s statues actually “walked” – and physics backs it up

A research team including Binghamton University archaeologist Carl Lipo has confirmed via 3D modeling and field experiments that the ancient people of Rapa Nui "walked" the iconic moai statues.
 Photo Credit: Carl Lipo

For years, researchers have puzzled over how the ancient people of Rapa Nui did the seemingly impossible and moved their iconic moai statues. Using a combination of physics, 3D modeling and on-the-ground experiments, a team including faculty at Binghamton University, State University of New York, has confirmed that the statues actually walked – with a little rope and remarkably few people.

Studying nearly 1,000 moai statues, Binghamton University Professor of Anthropology Carl Lipo and the University of Arizona’s Terry Hunt found that the people of Rapa Nui likely used rope and “walked” the giant statues in a zig-zag motion along carefully designed roads.

Researchers on the verge of solving Mexican mystery

The Mesoamerican city of Teotihuacan in central Mexico.
Photo Credit: Christophe Helmke, University of Copenhagen

More than two millennia ago, Teotihuacan was a thriving metropolis in central Mexico with up to 125,000 inhabitants. The city had gigantic pyramids and was a cultural center in Mesoamerica at the time.

But the city, which today consists of ruins and is a popular destination for both archaeologists and tourists, holds a great mystery. Who were its inhabitants?

Researchers Magnus Pharao Hansen and Christopher Helmke from the University of Copenhagen have presented a possible solution to the mystery in the renowned journal Current Anthropology.

By analyzing the signs on Teotihuacan's colorful murals and many other artefacts, they have concluded that the signs constitute an actual writing system, and they believe that this writing records an early form of the Uto-Aztecan language, which a thousand years later developed into the languages Cora, Huichol, and Nahuatl, the language of the Aztecs.

The life of a Stone Age man has been mapped

Illustration Credit: Niels Bach
CC-BY 4.0

Researchers have mapped the life of a Stone Age man in detail. New scientific methods have revolutionized archaeology and the Swedish-Danish team of researchers at the University of Gothenburg are now able to state that “Vittrup Man”, a Stone Age man found in a bog in Denmark, travelled across a wide geographical area during his lifetime.

Vittrup Man was first discovered in 1915. His skull had been split by at least eight blows from a club and his body placed in a wetland in north Jutland. Until recently, this was all we knew about him. Researchers now know that he had travelled a long way before his death in about 3200 BCE. He must have led an interesting life.

“He comes from the north, from a relatively cold area, and it must have been a coastal area because the food he ate as a child came from the sea,” says archaeologist Karl-Göran Sjögren, a member of the research team.

Viking dentistry was surprisingly advanced

Teeth from individuals among the Viking Age population of Varnhem in Västergötland, Sweden, are clinically examined by Carolina Bertilsson at the Institute of Odontology.
Photo Credit: Yoichi Ishizuka

Widespread caries and toothache – but also some dental work and filing of front teeth. Viking Age teeth from Varnhem bear witness to surprisingly advanced dentistry. This has been shown in a study carried out at the University of Gothenburg.

The study examined 3,293 teeth from 171 individuals among the Viking Age population of Varnhem in Västergötland, Sweden. The site is known for extensive excavations of Viking and medieval environments, including tombs where skeletons and teeth have been preserved well in favorable soil conditions.

The research team from the University of Gothenburg’s Institute of Odontology worked with an osteologist from Västergötland’s Museum. The skulls and teeth were transported to Gothenburg, where all the examinations were carried out.

The teeth underwent clinical examinations using standard dentistry tools under bright light. A number of X-ray examinations were also performed using the same technique used in dentistry, where the patient bites down on a small square imaging plate in the mouth.

Plague from Egypt: topos or reality?

Fortress in Alexandria, Egypt
From Alexandria and Pelusium, goods and people traveled from Egypt to the entire Mediterranean region. Did epidemics also spread along this route?
Photo Credit: Juan Nino

Many reports from antiquity about outbreaks of plague mention Egypt as the source of pestilences that reached the Mediterranean. But was this really the case? Researchers from the University of Basel are conducting a critical analysis of the ancient written and documentary evidence combined with archaeogenetic findings to add some context to the traditional view.

Red and inflamed eyes, bad breath, fever, violent convulsions, boils and blisters over the entire body: these and other symptoms are mentioned by historian Thucydides in connection with the “Plague of Athens”, which lasted from 430 to 426 BCE. He suspected that the epidemic originated in Aithiopia. “This area isn’t to be confused with the country we now know as Ethiopia, but was a more general term used at the time to refer to the region south of Egypt,” explains Professor Sabine Huebner, Professor of Ancient History at the University of Basel.

Contemporary accounts suggest that later epidemics in the Mediterranean also started in Egypt and Aithiopia, such as the Antonine Plague, the Plague of Cyprian and the Justinianic Plague, which ravaged the ancient world between the second and sixth centuries.

The encounter between Neanderthals and Sapiens as told by their genomes

analysed the distribution of the portion of DNA inherited from Neanderthals in the genomes of humans (Homo sapiens) over the last 40,000 years.
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Image Credit: © Claudio Quilodrán

About 40,000 years ago, Neanderthals, who had lived for hundreds of thousands of years in the western part of the Eurasian continent, gave way to Homo sapiens, who had arrived from Africa. This replacement was not sudden, and the two species coexisted for a few millennia, resulting in the integration of Neanderthal DNA into the genome of Sapiens. Researchers at the University of Geneva (UNIGE) have analyzed the distribution of the portion of DNA inherited from Neanderthals in the genomes of humans (Homo sapiens) over the last 40,000 years. These statistical analyses revealed subtle variations in time and geographical space. This work, published in the journal Science Advances, helps us to understand the common history of these two species. 

Thanks to genome sequencing and comparative analysis, it is established that Neanderthals and Sapiens interbred and that these encounters were sometimes fruitful, leading to the presence of about 2% of DNA of Neanderthal origin in present-day Eurasians. However, this percentage varies slightly between regions of Eurasia, since DNA from Neanderthals is somewhat more abundant in the genomes of Asian populations than in those of European populations. 

Climate and human land use both play roles in Pacific island wildfires past and present

SMU fire scientist Christopher Roos
Photo Credit: Courtesy of  Southern Methodist University

It’s long been understood that human settlement contributes to conditions that make Pacific Islands more susceptible to wildfires, such as the devastating Aug. 8 event that destroyed the Maui community of Lahaina. But a new study from SMU fire scientist Christopher Roos published in the journal Nature Ecology & Evolution shows that climate is an undervalued part of the equation.

Roos, SMU environmental archaeologist and professor of anthropology, traveled with his team to the Sigatoka River valley in southwestern Fiji in 2013, where they collected charcoal and stable carbon isotopes from deep soil cores to understand historic patterns of fire activity in the area. Different plants have distinct carbon isotopic signatures, which can provide information about past plant communities.

The team found fires and fire-created grassy areas that predate human settlement by millennia and actively corresponded to droughts likely driven by a regularly occurring weather pattern known as El Niño. El Niño events can alter precipitation patterns worldwide, making environmental conditions more favorable for wildfires. The National Oceanic and Atmospheric Administration issued an El Niño advisory in June, announcing the latest arrival of the climate event that continues to influence weather worldwide.

New study shows signs of early creation of modern human identities

SapienCE researchers have publiched a new study which provides vital information about how and when we may have started developing modern human identities. Image showing excavation at Blombos Cave, South Africa.
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Resized Image using AI by SFLORG
Photo Credit: UiB, SapienCE

The study, which is newly published in the Journal of Human Evolution, confirms previous scant evidence, and supports a multistep evolutionary scenario for the culturalization of the human body.

Eye-catching shells made into ornaments

The new study is conducted by Francesco d'Errico, Karen Loise van Niekerk, Lila Geis and Christopher Stuart Henshilwood. The significant findings provide vital information about how and when we may have started developing modern human identities.

“The discovery of eye-catching unmodified shells with natural holes from 100 to 73 ka confirms previous scant evidence that marine shells were collected, taken to the site and, in some cases, perhaps worn as personal ornaments before a stage in which shells belonging to selected species were systematically, and intentionally perforated with suitable techniques to create composite beadworks”, van Niekerk says.

Similar shells have been found in North Africa, other sites in South Africa and the Mediterranean Levant, which means that the argument is supported by evidence from other sites, not just Blombos Cave.

Hunting anything that flies

Pillar from Göbekli Tepe depicting a vulture with its wings spread. 
Photo Credit: © Nadja Pöllath / SNSB-SPM

Birds were an important source of food for hunter-gatherer communities in Upper Mesopotamia at the beginning of the Neolithic period. Besides mammals, ranging from aurochs to hares, or fish, foragers also pursued an impressively large spectrum of bird species in Southeast Anatolia 11,000 years ago. They were hunted mainly, but not exclusively, in autumn and winter – at the time of year, when many bird species form larger flocks and migratory birds cross the area. The species lists are therefore very extensive: At the famous Early Neolithic settlement and the world's oldest temple complex of Göbekli Tepe, for example, c. 18 km northeast of present-day Şanlıurfa (SE Anatolia, Turkey), the researchers identified the remains of at least 84 bird species. Dr. Nadja Pöllath, curator at the Bavarian State Collection for Palaeoanatomy (Staatssammlung für Paläoanatomie München SNSB-SPM) and Prof. Joris Peters, chair of the Institute for Palaeoanatomy, Domestication Research and History of Veterinary Medicine at LMU München and director of the state collection, identified the Neolithic bird bones with the aid of the reference skeletons of the state collection.

The researchers were surprised by the large number of small passerine birds identified at Göbekli Tepe, comprising mainly starlings and buntings. In principle, the Early Neolithic inhabitants of Göbekli Tepe hunted birds in all habitats – mainly in the open grassland and wooded steppe in their direct surroundings, but also in the wetlands and gallery forest somewhat further away.

New insights into the origin of food sharing among humans

Chimpanzees Gremlin and son Grendel, begging for food, at Gombe National Park, Tanzania.
Photo Credit: Courtesy of University of Minnesota

As humans evolved to hunt, gather and share food, cooperation provided a key to our success as a species. While chimpanzees and other primates sometimes share food, humans stand out. As hunter-gatherers — the subsistence strategy that all humans followed until the invention of agriculture — our survival depended on daily sharing of food between unrelated adult males and females. 

While hunter-gatherers today depend heavily on hunting and cooking, long before these activities became important for our ancestors, species such as Australopithecus extracted foods such as roots, tubers and nuts. Since hunter-gatherers and nonhuman primates tend to share foods that are large, valuable and divisible, these nutrient-dense foods are likely candidates for sharing, and may have been susceptible to theft by hungry group members. 

In new research published in the Proceedings of the National Academy of Sciences (PNAS), a team led by College of Biological Sciences Professor Michael Wilson developed a conceptual and mathematical model of the evolution of food production and sharing in early human ancestors. The interdisciplinary team included an economist, a theoretical biologist, an anthropologist and a primatologist. 

Romantic Love in Humans May Have Evolved From Same-Sex Friendship

Two adolescent male chimpanzees, Barron, 15, and PeeWee, 9, grooming.
Photo Credit: Aaron Sandel.

Romantic heterosexual relationships in humans may have evolved from same-sex pairings in a common ancestor of humans and chimpanzees, according to a novel hypothesis by a researcher at The University of Texas at Austin.

The prevailing explanation of heterosexual pair bonding and romantic love in humans is that it evolved from the mother-infant bond present in many mammals. In a paper published in the journal Evolutionary Anthropology, anthropology professor Aaron Sandel cites primate research — including his own decadelong studies of chimpanzees in Kibale National Park, Uganda — to propose instead that this behavior evolved in humans from same-sex pair bonding already present in a common ancestor of humans and chimpanzees.

A pair bond is a cooperative relationship between nonrelated adults that remains stable over time and includes an emotional connection, rather than being merely transactional. Chimpanzees, humans’ closest relative, do not pair bond with their mates, but adult males of the species form same-sex bonds lasting as long as 13 years.

New Model for Human Evolution Suggests Homo Sapiens Arose from Multiple Closely Related Populations

View of the village of Kuboes, on the border of South Africa and Namibia. DNA samples were collected from Nama individuals who have historically lived in the region.
Photo Credit: Brenna Henn/UC Davis

In testing the genetic material of current populations in Africa and comparing against existing fossil evidence of early Homo sapiens populations there, researchers have uncovered a new model of human evolution — overturning previous beliefs that a single African population gave rise to all humans. The new research was published today, May 17, in the journal Nature.

Although it is widely understood that Homo sapiens originated in Africa, uncertainty surrounds how branches of human evolution diverged and how people migrated across the continent, said Brenna Henn, professor of anthropology and the Genome Center at UC Davis, corresponding author of the research.

“This uncertainty is due to limited fossil and ancient genomic data, and to the fact that the fossil record does not always align with expectations from models built using modern DNA,” she said. “This new research changes the origin of species.”

Research co-led by Henn and Simon Gravel of McGill University tested a range of competing models of evolution and migration across Africa proposed in the paleoanthropological and genetics literature, incorporating population genome data from southern, eastern and western Africa.

Apes may have evolved upright stature for leaves, not fruit, in open woodland habitats

Artistic rendering of the open woodland habitat reconstruction at Moroto II with Morotopithecus bishopi vertically climbing with infant on back and juvenile below. Active volcano (Mount Moroto) is in background. Fossil relative of an elephant (Prodeinotherium) is foraging in center back.
Illustration Credit: Corbin Rainbolt

Anthropologists have long thought that our ape ancestors evolved an upright torso in order to pick fruit in forests, but new research from the University of Michigan suggests a life in open woodlands and a diet that included leaves drove apes’ upright stature.

The findings shed light on ape origins and push back the origin of grassy woodlands from between 7 million and 10 million years ago to 21 million years ago in equatorial Africa, during the Early Miocene.

Fruit grows on the spindly peripheries of trees. To reach it, large apes need to distribute their weight on branches stemming from the trunk, then reach out with their hands toward their prize. This is much easier if an ape is upright because it can more easily grab onto different branches with its hands and feet. If its back is horizontal, then its hands and feet are generally underneath the body, making it much harder to move outward to the smaller branches of a tree—especially if the ape is large bodied.

Ancient DNA reveals entwined African and Asian ancestry along the Swahili coast of eastern Africa

Rice researchers Mary Prendergast and Jeffrey Fleisher.
Photo Credit: Brandon Martin.

A new genetic study of medieval people who lived along the Indian Ocean coast of eastern Africa — an area often called the “Swahili coast” for its language and culture — revealed that they had both African and Persian ancestry.

The results suggest that maritime trade connections long recognized by archaeologists based on imported goods and architectural influences fostered relationships between Asian merchants and African traders and their families.

“Entwined African and Asian genetic roots of medieval peoples of the Swahili coast” was published today in Nature. It examines genetic ancestry and cultural influences in eastern Africa by using DNA from the skeletal remains of 80 individuals who were buried in six medieval and early modern coastal towns in Kenya and Tanzania dating to the years 1250-1800 and an inland town in Kenya dating to after 1650.

Analysis of the genetic data enabled scientists to estimate that people of African and Persian ancestry began to have children together around the year 1000, centuries before the burials themselves.

23,000-year-old human genome from southern Spain decoded

Human tooth recovered Cueva de Malalmuerzo
Photo Credit: Pedro Cantalejo

A new study reports on genomic data from a 23,000-year-old individual who lived in what was probably the warmest place in Europe at the peak of the last Ice Age. The oldest human genome recovered from the southern tip of Spain adds an important piece of the puzzle to the genetic history of Europe.

An international team of researchers has analyzed ancient human DNA from several archaeological sites in Andalucía in southern Spain. The study, published in Nature Ecology and Evolution, reports on the oldest genome to date from Cueva del Malalmuerzo in southern Spain, as well as the 7,000 to 5,000-year-old genomes of early farmers from other well-known sites, such as Cueva de Ardales. The researchers describe their findings in the article ‘A 23,000-year-old southern-Iberian individual links human groups that lived in Western Europe before and after the Last Glacial Maximum’ in the Journal Nature Ecology and Evolution.

The Iberian Peninsula plays an important role in the reconstruction of human population history. As a geographic cul-de-sac in the southwest of Europe, it is on one hand considered a refuge during the last Ice Age with its drastic temperature fluctuations. On the other hand, it may have been one of the starting points for the recolonization of Europe after the glacial maximum. Indeed, previous studies had reported on the genomic profiles of 13,000 to 8,000-year-old hunter-gatherers from the Iberian Peninsula and provided evidence for the survival and continuation of a much older Paleolithic lineage that has been replaced in other parts of Europe and is no longer detectable. 

New Study Shows Archery Appeared in Europe Thousands of Years Earlier than Previously Thought

Laure Metz making experimental bow and arrow shots with arrows armed with Neronian light points.
 Photo Credit: Ludovic Slimak

The use of bow-and-arrow technology gave humans an edge over Neanderthal neighbors in hunting game

A new study published in Science Advances contextualizes the traditions and technological knowledge of early, pioneering Homo sapiens. The study demonstrates the mastery of archery by modern populations and extends the evidence of archery in Europe back by about 40,000 years.

The researchers analyzed lithic artifacts from a cave in Mediterranean France called Grotte Mandrin, which reveals the oldest occupation of modern humans on the European continent. The study focuses on a very rich level, attributed to the Neronian culture, and testifies to Homo sapiens occupations dating back 54,000 years, interposed between numerous Neanderthal occupations in the cave before and after the modern humans. That’s roughly 10,000 years earlier than what had been previously believed to be the earliest occupation of modern humans in Europe.

The research was directed by Laure Metz, an associated researcher at UMR 7269 (UMR LAMPEA, CNRS, Aix-Marseille University), and Ludovic Slimak, CNRS researcher (UMR 5608 TRACES, Toulouse Jean Jaurès University). Metz is a UConn-affiliated researcher and former post-doctoral researcher in the UConn Department of Anthropology Deep History Lab led by Professor Christian Tryon.

Early humans: Annual cycles in tooth enamel provide insights into life histories

Jülide Kubat and Wolfgang Müller load the LA-ICPMS with a thin section of tooth for analysis.
Photo Credit: Jülide Kubat

An interdisciplinary team of scientists, led by Goethe University Frankfurt and the Senckenberg Research Institute and Natural History Museum Frankfurt, has discovered – by analyzing their teeth – what our ancestors of the species Homo erectus ate hundreds of thousands of years ago on the island of Java in Southeast Asia: over the course of a year, these early humans switched from a plant-based diet to a mixed one, but were far less dependent on seasonal food supply than, for example, orangutans, which also inhabited the island.

If you take a magnifying glass and a torch and look at your teeth very carefully in the mirror, in places you can spot a pattern of fine, parallel lines running across your teeth. These correspond to the striae of Retzius that mark the growth of our tooth enamel. Enamel starts forming in the womb and continues to mineralize until adolescence, when the last milk teeth fall out and are replaced by permanent ones. Like in all land-dwelling vertebrates, tooth enamel mineralizes gradually in microscopically thin layers in humans too, represented by the striae of Retzius. The speed with which a human develops can be read from these Retzius lines. Physiological changes, such as birth, weaning or illness, for example, leave distinctive traces. The striae of Retzius also form the chronological framework for the chemical composition of tooth enamel, which in turn reflects changes in the diet of that individual.

New study suggests Mayas utilized market-based economics

Obsidian collections from the site of Q'umarkaj and the surrounding region.
Photo Credit: Rachel Horowitz

More than 500 years ago in the midwestern Guatemalan highlands, Maya people bought and sold goods with far less oversight from their rulers than many archeologists previously thought.

That’s according to a new study in Latin American Antiquity that shows the ruling K’iche’ elite took a hands-off approach when it came to managing the procurement and trade of obsidian by people outside their region of central control.

In these areas, access to nearby sources of obsidian, a glasslike rock used to make tools and weapons, was managed by local people through independent and diverse acquisition networks. Over time, the availability of obsidian resources and the prevalence of craftsmen to shape it resulted in a system that is in many ways suggestive of contemporary market-based economies.

“Scholars have generally assumed that the obsidian trade was managed by Maya rulers, but our research shows that this wasn’t the case at least in this area,” said Rachel Horowitz, lead author of the study and an assistant professor of anthropology at Washington State University. “People seem to have had a good deal of economic freedom including being able to go to places similar to the supermarkets we have today to buy and sell goods from craftsmen.”

Early humans may have first walked upright in the trees

Photo Credit: Alexa

Human bipedalism – walking upright on two legs – may have evolved in trees, and not on the ground as previously thought, according to a new study involving UCL researchers.

In the study, published in the journal Science Advances, researchers from UCL, the University of Kent, and Duke University, USA, explored the behaviors of wild chimpanzees - our closest living relative - living in the Issa Valley of western Tanzania, within the region of the East African Rift Valley.

Known as ‘savanna-mosaic’ – a mix of dry open land with few trees and patches of dense forest - the chimpanzees’ habitat is very similar to that of our earliest human ancestors and was chosen to enable the scientists to explore whether the openness of this type of landscape could have encouraged bipedalism in hominins.

The study is the first of its kind to explore if savanna-mosaic habitats would account for increased time spent on the ground by the Issa chimpanzees, and compares their behavior to other studies on their solely forest-dwelling cousins in other parts of Africa.

Overall, the study found that the Issa chimpanzees spent as much time in the trees as other chimpanzees living in dense forests, despite their more open habitat, and were not more terrestrial (land-based) as expected.