Brain development differs between Neanderthals and modern humans

 

Dresden and Leipzig researchers find that stem cells in the developing brain of modern humans take longer to divide and make fewer errors when distributing their chromosomes to their daughter cells, compared to those of Neanderthals

Peer-Reviewed Publication

MAX PLANCK INSTITUTE OF MOLECULAR CELL BIOLOGY AND GENETICS (MPI-CBG)

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IMAGE: LEFT SIDE: MICROSCOPY IMAGE OF THE CHROMOSOMES (IN CYAN) OF A MODERN HUMAN NEURAL STEM CELL OF THE NEOCORTEX DURING CELL DIVISION. RIGHT SIDE: SAME TYPE OF IMAGE, BUT OF A CELL WHERE THREE AMINO ACIDS IN THE TWO PROTEINS KIF18A AND KNL1, INVOLVED IN CHROMOSOME SEPARATION, HAVE BEEN CHANGED FROM THE MODERN HUMAN TO THE NEANDERTHAL VARIANTS. THESE “NEANDERTHALIZED” CELLS SHOW TWICE AS MANY CHROMOSOME SEPARATION ERRORS (RED ARROW). view more 

CREDIT: FELIPE MORA-BERMÚDEZ / MPI-CBG

After the ancestors of modern humans split from those of Neanderthals and Denisovans, their Asian relatives, about one hundred amino acids, the building blocks of proteins in cells and tissues, changed in modern humans and spread to almost all modern humans. The biological significance of these changes is largely unknown. However, six of those amino acid changes occurred in three proteins that play key roles in the distribution of chromosomes, the carriers of genetic information, to the two daughter cells during cell division.

The effects of the modern human variants on brain development

To investigate the significance of these six changes for neocortex development, the scientists first introduced the modern human variants in mice. Mice are identical to Neanderthals at those six amino acid positions, so these changes made them a model for the developing modern human brain. Felipe Mora-Bermúdez, the lead author of the study, describes the discovery: “We found that three modern human amino acids in two of the proteins cause a longer metaphase, a phase where chromosomes are prepared for cell division, and this results in fewer errors when the chromosomes are distributed to the daughter cells of the neural stem cells, just like in modern humans.” To check if the Neanderthal set of amino acids have the opposite effect, the researchers then introduced the ancestral amino acids in human brain organoids – miniature organ-like structures that can be grown from human stem cells in cell culture dishes in the lab and that mimic aspects of early human brain development. “In this case, metaphase became shorter and we found more chromosome distribution errors.” According to Mora-Bermúdez, this shows that those three modern human amino acid changes in the proteins known as KIF18a and KNL1 are responsible for the fewer chromosome distribution mistakes seen in modern humans as compared to Neanderthal models and chimpanzees. He adds that “having mistakes in the number of chromosomes is usually not a good idea for cells, as can be seen in disorders like trisomies and cancer.”

“Our study implies that some aspects of modern human brain evolution and function may be independent of brain size since Neanderthals and modern humans have similar-sized brains. The findings also suggest that brain function in Neanderthals may have been more affected by chromosome errors than that of modern humans,” summarizes Wieland Huttner, who co-supervised the study. Svante Pääbo, who also co-supervised the study, adds that “future studies are needed to investigate whether the decreased error rate affects modern human traits related to brain function.”

Early hunting, farming homogenized mammal communities of North America

Whether by the spear or the plow, humans have been homogenizing the mammal communities of North America for 10,000-plus years, says new research led by the University of Nebraska–Lincoln and the Canadian Museum of Nature.

Nebraska’s Kate Lyons, the CMN’s Danielle Fraser and international colleagues conducted an analysis of 8,831 fossils representing 365 mammal species from 366 sites across North America. Relying on those fossil records allowed the team to assess homogenization: the degree to which the specific mammal species in one ecological community resembled the species composition of its surrounding communities.

A few prior studies — those examining North American mammals from tens of millions to millions of years ago — generally pegged climate as the primary culprit of the homogenization and heterogenization they uncovered. Other research, focusing on just the past century to last few decades, has chronicled the recent human influences of land conversion, poaching and territorial encroachment.

But no team had established a baseline of homogenization, or the true magnitude of human contributions to it, by examining the phenomenon both before and after the arrival of Homo sapiens. So Fraser, Lyons and their colleagues trained their attention on the past 30,000 years, a timespan encompassing the absence of Homo sapiens on the continent, their migration throughout it, and their shift from hunting-gathering to intensive agriculture.

Homo sapiens, the team found, are probably most responsible for the unprecedented rates and levels of homogenization seen in North American mammal communities — for flattening their distinctive character by escalating the similarity among many of them.

“Our conclusion is that this does have to do with early human activities and the arrival of humans into the Americas,” said Lyons, assistant professor of biological sciences at Nebraska.

North American mammal communities of the modern day are more than twice as homogenous as they were roughly 10,000 years ago, the study revealed, and could wind up nearly four times as homogenous by the end of the 21st century. That shift, the researchers said, is equivalent to the current difference in homogenization between the subtropics of central Mexico and the comparatively uniform mammal communities of the Arctic.

The trend emerged earlier and was especially pronounced among mammals weighing at least 1 kilogram, or 2.2 pounds. Also telling? Homogenization began accelerating about 12,000 years ago, around the time that humans were hunting mammoths, saber-toothed cats, dire wolves and other massive mammals to extinction.

Together, Lyons said, those findings suggest that the spate of large-mammal extinctions contributed to homogenization. The disappearance of large mammals unique to individual communities would have directly increased their similarity, she said. And in a 2019 study, Lyons and colleagues showed that those extinctions also drove smaller species to expand their ranges, filling the geographic voids left by their larger counterparts. Expansion would have led to more territorial overlap, Lyons said, further homogenizing communities in the process.

But homogenization in North America accelerated even more over the past 5,000 years — a span marked by as much as a 10-fold surge in the human population and the emergence of widespread farming, particularly across what would become the central and eastern United States.

“It happened much later in North America than on other continents,” Lyons said. “But that’s really when humans in North America went from being hunter-gatherers to being more settled and dependent on agriculture.”

The proliferation of human settlements across the continent attracted mammal species — coyotes, raccoons, rats and other rodents — that would come to thrive on the byproducts of those settlements and enjoy the elimination of predators by the people inhabiting them.

The conversion of prairies and forests for agriculture, meanwhile, shrunk the number of plant species in a given habitat from hundreds or thousands to mere dozens or fewer, narrowing the habitable territory for pickier herbivores and the carnivores or omnivores preying on them. Cultivated fields, roads and other human-created boundaries would also have acted as “barriers to dispersal,” Lyons said, that likewise hemmed certain species into smaller territories.

“You still have narrow-ranging species, but now they’re in fewer communities, so their overall contribution to the difference in communities is much smaller than maybe it was before,” Lyons said.

As for the potential effect of climate? The team found scant evidence for it between 10,000 and 500 years ago. From about 20,000 to 15,000 years ago, a warming North America saw the retreat of glaciers that had enveloped nearly all of modern-day Canada and much of the northern United States. Warmer climates generally yield more gradual north-south gradients in temperature and precipitation. That warming-driven homogeneity in climate, Lyons said, tends to breed homogeneity in mammal communities, too.

If climate had contributed to the homogenization of mammal communities, the team would have expected that homogenization to accelerate prior to 10,000 years ago. The fact that it didn’t indicates that climate probably had little to do with it, she said.

“What we find when we look at the climate patterns,” Lyons said, “is that all of that happened very early on, before we see this dramatic homogenization.”

For all the speed and severity of homogenization throughout the past 5,000 years, it has only increased in the past 500, the team concluded. To the extent that it’s stemming from the continued extinctions of keystone species whose behaviors and capabilities are especially consequential, that homogenization could spell danger for ecosystems, Lyons said.

“A lot of what we’re finding is that when we lose species — particularly when we lose large species that tend to be what we call ecosystem engineers — there’s a dramatic change in the ecosystem that’s left,” she said. “Large mammals do all kinds of stuff in ecosystems.

“Elephants eat a lot, they move around a lot, and they poop a lot, so they actually move nutrients around ecosystems a lot. What we’re finding, then, is that nutrients essentially get lost from ecosystems (in their absence).”

With fewer keystone species, homogenized mammal communities may also boast fewer ways to respond, and possibly survive, the ongoing challenges of climate change and further human encroachment, Lyons said.

“Communities will be probably less resilient to future perturbations and potential extinctions,” she said. “It also just makes the world less interesting, because you have less wondrous variation out there.”

The team reported its findings in the journal Nature Communications. Fraser and Lyons authored the study with Alex Shupinski, doctoral student in biological sciences at Nebraska; Amelia Villaseñor from the University of Arkansas; Anikó Tóth from the University of New South Wales; Meghan Balk of the Battelle Memorial Institute; Jussi Eronen from the University of Helsinki; W. Andrew Barr of The George Washington University; A. K. Behrensmeyer, Gary Graves, Richard Potts and Laura Soul, from the Smithsonian Institution; Matt Davis from the Natural History Museum of Los Angeles County; Andrew Du of Colorado State University; J. Tyler Faith from the University of Utah; Nicholas Gotelli from the University of Vermont; Advait Jukar of Yale University; Cindy Looy from the University of California, Berkeley; Brian McGill from the University of Maine; Joshua Miller from the University of Cincinnati; Silvia Pineda-Munoz of Indiana University.

The researchers received funding in part from the National Science Foundation and the Smithsonian Institution.

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JOURNAL

Nature Communications

DOI

10.1038/s41467-022-31595-8 

High-status Danish Vikings wore exotic beaver furs

Beaver fur was a symbol of wealth and an important trade item in 10th Century Denmark, according to a study published July 27, 2022 in the open-access journal PLOS ONE by Luise Ørsted Brandt of the University of Copenhagen and colleagues.

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CAPTION

Map of studied sites (a) and examples of included fur: b) Hvilehøj C4273-97, fragment 1, c) Hvilehøj C4280c, d) Bjerringhøj C143. Graphics: Luise Ørsted Brandt and Charlotte Rimstad. Photos: Roberto Fortuna, National Museum of Denmark.

Written sources indicate that fur was a key commodity during the Viking Age, between 800-1050 CE, but fur doesn’t often survive well in the archaeological record, so little direct evidence is available. Previous reports have used the microscopic anatomy of ancient fur to identify species of origin, but this method is often inexact. All in all, not much is known about the kinds of furs the Vikings preferred.

In this study, Brandt and colleagues analyzed animal remains from six high-status graves from 10th Century Denmark. While no ancient DNA was recovered from the samples, perhaps due to treatment processes performed on furs and skins and probably due to preservation conditions, identifiable proteins were recovered by two different analytical techniques. Grave furnishings and accessories included skins from domestic animals, while clothing exhibited furs from wild animals, specifically a weasel, a squirrel, and beavers.

These findings support the idea that fur was a symbol of wealth during the Viking Age. The fact that beavers are not native to Denmark suggests this fur was a luxury item acquired through trade. Some clothing items included fur from multiple species, demonstrating a knowledge of the varying functions of different animal hides, and may have indicated a desire to show off exclusive furs. The authors note the biggest limiting factor in this sort of study is the incompleteness of comparative protein databases; as these databases expand, more specific identifications of ancient animal skins and furs will be possible.

The authors add: “In the Viking Age, wearing exotic fur was almost certainly an obvious visual statement of affluence and social status, similar to high-end fashion in today's world. This study uses ancient proteins preserved in elite Danish Viking burials to provide direct evidence of beaver fur trade and use.”

: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0270040

Prehistoric roots of ‘cold sore’ virus traced through ancient herpes DNA

 

IMAGE: ONE OF THE SAMPLES OF ANCIENT HERPES DNA USED IN THE STUDY CAME FROM A MALE OF 26-35 YEARS OLD, EXCAVATED NEAR THE BANKS OF THE RHINE. THE MAN WAS A FERVENT SMOKER OF CLAY PIPES. TRACES OF THE HABIT ARE VISIBLE IN MULTIPLE PLACES ON THE TEETH, WHERE THE HARD CLAY PIPE, USUALLY PUT IN THE SAME PLACE IN THE MOUTH, HAS WORN THE TEETH. view more 

CREDIT: DR BARBARA VESELKA

Ancient genomes from the herpes virus that commonly causes lip sores – and currently infects some 3.7 billion people globally – have been uncovered and sequenced for the first time by an international team of scientists led by the University of Cambridge. 

Latest research suggests that the HSV-1 virus strain behind facial herpes as we know it today arose around five thousand years ago, in the wake of vast Bronze Age migrations into Europe from the Steppe grasslands of Eurasia, and associated population booms that drove rates of transmission.

Herpes has a history stretching back millions of years, and forms of the virus infect species from bats to coral. Despite its contemporary prevalence among humans, however, scientists say that ancient examples of HSV-1 were surprisingly hard to find.

The authors of the study, published in the journal Science Advances, say the Neolithic flourishing of facial herpes detected in the ancient DNA may have coincided with the advent of a new cultural practice imported from the east: romantic and sexual kissing.    

“The world has watched COVID-19 mutate at a rapid rate over weeks and months. A virus like herpes evolves on a far grander timescale,” said co-senior author Dr Charlotte Houldcroft, from Cambridge’s Department of Genetics.

“Facial herpes hides in its host for life and only transmits through oral contact, so mutations occur slowly over centuries and millennia. We need to do deep time investigations to understand how DNA viruses like this evolve,” she said. “Previously, genetic data for herpes only went back to 1925.”

The team managed to hunt down herpes in the remains of four individuals stretching over a thousand-year period, and extract viral DNA from the roots of teeth. Herpes often flares up with mouth infections: at least two of the ancient cadavers had gum disease and a third smoked tobacco.

The oldest sample came from an adult male excavated in Russia’s Ural Mountain region, dating from the late Iron Age around 1,500 years ago.

Two further samples were local to Cambridge, UK. One a female from an early Anglo-Saxon cemetery a few miles south of the city, dating from 6-7th centuries CE. The other a young adult male from the late 14th century, buried in the grounds of medieval Cambridge’s charitable hospital (later to become St. John’s College), who had suffered appalling dental abscesses. 

The final sample came from a young adult male excavated in Holland: a fervent clay pipe smoker, most likely massacred by a French attack on his village by the banks of the Rhine in 1672. 

“We screened ancient DNA samples from around 3,000 archaeological finds and got just four herpes hits,” said co-lead author Dr Meriam Guellil, from Tartu University’s Institute of Genomics.

“By comparing ancient DNA with herpes samples from the 20th century, we were able to analyse the differences and estimate a mutation rate, and consequently a timeline for virus evolution,” said co-lead author Dr Lucy van Dorp, from the UCL Genetics Institute.     

Co-senior author Dr Christiana Scheib, Research Fellow at St. John’s College, University of Cambridge, and Head of the Ancient DNA lab at Tartu University, said: “Every primate species has a form of herpes, so we assume it has been with us since our own species left Africa.”

“However, something happened around five thousand years ago that allowed one strain of herpes to overtake all others, possibly an increase in transmissions, which could have been linked to kissing.”

The researchers point out that the earliest known record of kissing is a Bronze Age manuscript from South Asia, and suggest the custom – far from universal in human cultures – may have travelled westward with migrations into Europe from Eurasia.   

In fact, centuries later, the Roman Emperor Tiberius tried to ban kissing at official functions to prevent disease spread, a decree that may have been herpes-related. However, for most of human prehistory, HSV-1 transmission would have been “vertical”: the same strain passing from infected mother to newborn child.

Two-thirds of the global population under the age of 50 now carry HSV-1, according to the World Health Organisation. For most of us, the occasional lip sores that result are embarrassing and uncomfortable, but in combination with other ailments – sepsis or even COVID-19, for example – the virus can be fatal. In 2018, two women died of HSV-1 infection in the UK following Caesarean births.

“Only genetic samples that are hundreds or even thousands of years old will allow us to understand how DNA viruses such as herpes and monkeypox, as well as our own immune systems, are adapting in response to each other,” said Houldcroft.

The team would like to trace this hardy primordial disease even deeper through time, to investigate its infection of early hominins. “Neanderthal herpes is my next mountain to climb,” added Scheib.

Oldest DNA from domesticated American horse lends credence to shipwreck folklore Peer-Reviewed Publication

 

 

IMAGE: THE ORIGIN OF ASSATEAGUE'S WILD HORSES HAS REMAINED A MYSTERY FOR CENTURIES, BUT NEW GENETIC DATA SUPPORTS THE THEORY THAT THEY DESCENDED FROM SPANISH HORSES MAROONED ON THE BARRIER ISLAND. view more 

CREDIT: FLORIDA MUSEUM PHOTO BY JEFF GAGE

An abandoned Caribbean colony unearthed centuries after it had been forgotten and a case of mistaken identity in the archaeological record have conspired to rewrite the history of a barrier island off the Virginia and Maryland coasts.

These seemingly unrelated threads were woven together when Nicolas Delsol, a postdoctoral researcher at the Florida Museum of Natural History, set out to analyze ancient DNA recovered from cow bones found in archaeological sites. Delsol wanted to understand how cattle were domesticated in the Americas, and the genetic information preserved in centuries-old teeth held the answer. But they also held a surprise.

“It was a serendipitous finding,” he said. “I was sequencing mitochondrial DNA from fossil cow teeth for my Ph.D. and realized something was very different with one of the specimens when I analyzed the sequences.”

That’s because the specimen in question, a fragment of an adult molar, wasn’t a cow tooth at all but instead once belonged to a horse. According to a study published this Wednesday in the journal PLOS ONE, the DNA obtained from the tooth is also the oldest ever sequenced for a domesticated horse from the Americas.  
The tooth was excavated from one of Spain’s first colonized settlements. Located on the island of Hispaniola, the town of Puerto Real was established in 1507 and served for decades as the last port of call for ships sailing from the Caribbean. But rampant piracy and the rise of illegal trade in the 16th century forced the Spanish to consolidate their power elsewhere on the island, and in 1578, residents were ordered to evacuate Puerto Real. The abandoned town was destroyed the following year by Spanish officials.

The remnants of the once-bustling port were inadvertently rediscovered by a medical missionary named William Hodges in 1975. Archaeological excavations of the site led by Florida Museum distinguished research curator Kathleen Deagan were carried out between 1979 and 1990.

Horse fossils and associated artifacts are incredibly rare at Puerto Real and similar sites from the time period, but cow remains are a common find. According to Delsol, this skewed ratio is primarily due to the way Spanish colonialists valued their livestock.

“Horses were reserved for individuals of high status, and owning one was a sign of prestige,” he said. “There are full-page descriptions of horses in the documents that chronicle the arrival of [Hernán] Cortés in Mexico, demonstrating how important they were to the Spanish.”

In contrast, cows were used as a source of meat and leather, and their bones were regularly discarded in communal waste piles called middens. But one community’s trash is an archaeologist’s treasure, as the refuse from middens often confers the clearest glimpse into what people ate and how they lived.

The specimen’s biggest surprise wasn’t revealed until Delsol compared its DNA with that of modern horses from around the world. Given that the Spanish brought their horses from the Iberian Peninsula in southern Europe, he expected horses still living in that region would be the closest living relatives of the 500-year-old Puerto Real specimen.

Instead, Delsol found its next of kin over 1,000 miles north of Hispaniola, on the island of Assateague off the coast of Maryland and Virginia. Feral horses have roamed freely across the long stretch of barrier island for hundreds of years, but exactly how they got there has remained a mystery.

According to the National Park Service, which manages the northern half of Assateague, the likeliest explanation is that the horses were brought over in the 1600s by English colonists from the mainland in an attempt to evade livestock taxes and fencing laws. Others believe the feral herds descended from horses that survived the shipwreck of a Spanish galleon and swam to shore, a theory popularized in the 1947 children’s novel “Misty of Chincoteague.” The book was later adapted to film, helping spread the shipwreck legend to an even wider audience.

Until now, there has been little evidence to support either theory. Proponents of the shipwreck theory claim it would be unlikely that English colonists would lose track of valuable livestock, while those in favor of an English origin of the herds point to the lack of sunken vessels nearby and the omission of feral horses in historical records of the region.

The results of the DNA analysis, however, unequivocally point to Spanish explorers as being the likeliest source of the horses on Assateague, Delsol explained.

“It’s not widely reported in the historical literature, but the Spanish were exploring this area of the mid-Atlantic pretty early on in the 16th century. The early colonial literature is often patchy and not completely thorough. Just because they don’t mention the horses doesn’t mean they weren’t there.”

The feral herds on Assateague weren’t the only horses to revert back to their wild heritage after arriving in the Americas. Colonists from all over Europe brought with them horses of various breeds and pedigrees, some of which bucked their bonds and escaped into the surrounding countryside.

Today, the U.S. Bureau of Land Management estimates there are roughly 86,000 wild horses across the country, most of which are located in western states, such as Nevada and Utah. Delsol hopes that future ancient DNA studies will help decode the complex history of equine introductions and migrations that occurred over the last several centuries and offer a clearer understanding of today’s diversity of wild and domesticated horses.

Floors in ancient Greek luxury villa were laid with recycled glass Peer-Reviewed Publication

 

IMAGE: EXCAVATION AND MOSAIC FLOORS OF VILLA. view more 

CREDIT: UNIVERSITY OF SOUTHERN DENMARK

Although this 1700 years old luxury villa was excavated and examined both in 1856 and in the 1990s, it still has secrets to reveal.

New secrets have now been revealed by an international research team, with Professor and expert in archaeometry, Kaare Lund Rasmussen from University of Southern Denmark leading the so called archaeometric analyses: using chemical analysis to determine which elements an object was made of, how it has been processed, etc.

Others in the team are Thomas Delbey from Cranfield University in England and the classical archaeologists Birte Poulsen and Poul Pedersen from Aarhus University and University of Southern Denmark. The team’s work is published in the journal Heritage Science, including archaeometric analysis of 19, approximately, 1600 years old mosaic tesserae.

One of seven wonders of the world

The tesserae originate from an excavation of a villa from late antiquity, located in Halikarnassos (today Bodrum in Anatolia, Turkey). Halikarnassos was famous for King Mausolus' giant and lavish tomb, which was considered one of the seven wonders of the world.

The villa was laid out around two courtyards and the many rooms were adorned with mosaic floors. In addition to geometric patterns, there were also motifs of various mythological figures and scenes taken from Greek mythology; e.g. Princess Europa being abducted by the god Zeus in the form of a bull and Aphrodite at sea in her seashell.

Motifs from the stories of the much younger Roman author Virgil are also represented.

Inscriptions in the floor have revealed that the owner was named Charidemos and that the villa was built in the mid-fifth century.

A costly luxury

Mosaic flooring was a costly luxury: expensive raw materials like white, green, black, and other colors of marble had to be transported from distant quarries. Other stone materials, ceramics and glasses also had to be imported.

- I received 19 mosaic tesserae for analysis in my lab in Denmark. Of these, seven were of glass in different colors; purple, yellow, red, and deep red. My conclusion is that six of them are probably made of recycled glass, says Kaare Lund Rasmussen.

This conclusion is based on a chemical analysis called inductively coupled plasma mass spectrometry. With it, the research team has determined the concentrations of no less than 27 elements, some of them all the way down to a concentration of billionths of a gram.

Waning of Roman Empire

- We were able to distinguish between base glass from Egypt and base glass from the Middle East and also, we could determine which elements were added by the ancient craftsmen to color the glasses and to make them opaque, which was preferred at the time, he says.

It is of course difficult to extrapolate from only seven glass mosaic tesserae, but the new results fit very well with the picture of Anatolia in late antiquity. As the power of the Roman Empire waned, trade routes were closed or rerouted, which probably led to a shortage of goods in many places - including raw materials for glass production in Anatolia.

This, together with the stories depicted on the floors, allows the classical archaeologists to put together a more detailed picture of what was fashionable in late antiquity and what the possibilities were for the artistic unfolding.

North 'plaza' in Cahokia was likely inundated year-round

 The ancient North American city of Cahokia had as its focal point a feature now known as Monks Mound, a giant earthwork surrounded on its north, south, east and west by large rectangular open areas. These flat zones, called plazas by archaeologists since the early 1960s, were thought to serve as communal areas that served the many mounds and structures of the city.

New paleoenvironmental analyses of the north plaza suggest it was almost always underwater, calling into question earlier interpretations of the north plaza's role in Cahokian society. The study is reported in the journal World Archaeology.

Cahokia was built in the vicinity of present-day St. Louis, beginning in about A.D. 1050. It grew, thrived for more than 300 years and was abandoned by 1400. Many mysteries surround the culture, layout and architecture of the city, in particular its relationship to water. Cahokia was built in a flood plain below the confluence of the Mississippi and Illinois rivers and would have been regularly infiltrated with flowing water, said Caitlin Rankin, a geoarchaeologist at the Illinois State Archaeological Survey who conducted the new research.

"Cahokia is the largest archaeological site in North America, but only about 1% of it has been excavated, so there's so much about the site that we don't know," Rankin said.

Early in her encounters with the city's layout, Rankin was baffled by the location and height of the north plaza.

"It's a really strange area because it's at a very low elevation, like the lowest elevation of the site," she said. "And it's in an old meander scar of the Mississippi River."

Two creeks ran through the area, and it likely flooded whenever the Mississippi swelled after heavy rains.

To investigate the site, Rankin conducted test excavations and extracted sediment cores around the four mounds that define the north plaza. She also took soil samples in the same meander scar less than 5 kilometers from the plaza and analyzed stable carbon isotopes in these modern soils to determine isotope differences between wetlands, seasonal wetlands and prairie environments. Comparing these with carbon isotopes from ancient soils chronologically associated with the mounds gave insight into what types of plants had grown there in the past.

"What I learned is that this area remained wet throughout the year," Rankin said. "There may have been some seasonal dryness, but overall, it was a wetland."

Her findings challenge previous notions about this site being a plaza, which is generally thought of as a dry open area across which people walk and congregate. "Generally, those places aren't underwater," Rankin said.

How the north plaza was used remains a mystery, she said, but the study adds to the evidence that water was a central element of the city.

"Water was important to the people of Cahokia for a number of reasons," she said. "They had a whole agricultural suite of wetland plants that they domesticated and relied on as food." Water also was essential to their trade with people up and down the Mississippi River. And the cosmological beliefs of many Indigenous groups include creation stories that involve complex interactions with sky, water and earth.

"At Cahokia, you have these mounds emerging from this watery sphere," she said. "And so that was a significant feature that probably resonated with their creation stories and their myths and their worldview."

The Illinois State Archaeological Survey is a division of the Prairie Research Institute at the University of Illinois Urbana-Champaign.

Archaeological investigations offer up new findings on the history of Parthian settlements in Iraqi Kurdistan

 The mountain fortress of Rabana-Merquly in modern Iraqi Kurdistan was one of the major regional centres of the Parthian Empire, which extended over parts of Iran and Mesopotamia approximately 2,000 years ago. This is a conclusion reached by a team of archaeologists led by Dr Michael Brown, a researcher at the Institute of Prehistory, Protohistory and Near-Eastern Archaeology of Heidelberg University. Together with Iraqi colleagues, Brown studied the remains of the fortress. Their work provides important insights into the settlement structures and history of the Parthians, about whom there is surprisingly little knowledge, emphasises Dr Brown, even though the annals of history record them as a major power. Furthermore, Rabana-Merquly may be the lost city of Natounia.

Situated on the southwest flanks of Mt. Piramagrun in the Zagros Mountains, the stone fortress of Rabana-Merquly comprises not only the nearly four-kilometre-long fortifications but also two smaller settlements for which it is named. Because of its high position on the mountain, mapping the site was possible only with drones. Within the framework of multiple excavation campaigns conducted from 2009 and most recently between 2019 and 2022, the international team of researchers was able to study the archaeological remains on site. Structures that have survived to this day suggest a military use and include the remains of several rectangular buildings that may have served as barracks. The researchers also found a religious complex possibly dedicated to the Zoroastrian Iranian goddess Anahita.

The rock reliefs at the entrance to the fortress are of special significance, along with the geographic location of the fortification in the catchment area of the Lower Zab River, known in antiquity by its Greek name of Kapros. The researchers suspect that Rabana-Merquly may be the lost city of Natounia. Until now, the existence of the royal city known as Natounia on the Kapros, or alternatively as Natounissarokerta, has been documented only on a few coins dating from the first century BC. According to one scientific interpretation, the place name Natounissarokerta is composed of the royal name Natounissar, the founder of the Adiabene royal dynasty, and the Parthian word for moat or fortification. "This description could apply to Rabana-Merquly," states Dr Brown.

According to the Heidelberg archaeologist, the wall reliefs at the entrance to the fortress could depict the city's founder, either Natounissar or a direct descendant. The researcher explains that the relief resembles a likeness of a king that was found approximately 230 kilometres away in Hatra, a location rich in finds from the Parthian era. The Rabana-Merquly mountain fortress is located on the eastern border of Adiabene, which was governed by the kings of a local dynasty dependent on the Parthians. It may have been used, among other things, to conduct trade with the pastoral tribes in the back country, maintain diplomatic relations, or exert military pressure. "The considerable effort that must have gone into planning, building, and maintaining a fortress of this size points to governmental activities," stresses Dr Brown.

The current research in Rabana-Merquly is being funded by the German Research Foundation as part of priority programme 2176, "The Iranian Highlands: Resilience and Integration of Premodern Societies." The aim of the research project is to investigate Parthian settlements and society in the Zagros highlands on both sides of the Iran-Iraq border. During the latest excavations at Rabana-Merquly, Dr Brown collaborated with colleagues from the Directorate of Antiquities in Sulaymaniyah, a city in the autonomous region of Iraqi Kurdistan. The results of the Heidelberg investigations were published in the journal "Antiquity."

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Story Source:

Materials provided by Heidelberg University. Note: Content may be edited for style and length.

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Related Multimedia:

• Discovery of Parthian settlements

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Journal Reference:

1. Michael Brown, Kamal Rasheed Raheem, Hashim Hama Abdullah. Rabana-Merquly: a fortress in the kingdom of Adiabene in the Zagros Mountains. Antiquity, 2022; 1 DOI: 10.15184/aqy.2022.74

She Who Wrote: Enheduanna and Women of Mesopotamia, ca. 3400-2000 B.C.

The Morgan Library & Museum proudly presents She Who Wrote: Enheduanna and Women of Mesopotamia, ca. 3400-2000 B.C opening October 14, 2022, and running through February 19, 2023. The exhibition brings together for the first time a comprehensive selection of artworks that capture the rich and expressions of women’s lives in ancient Mesopotamia during the late fourth and third millennia BC. It centers on the high priestess and poet Enheduanna (ca. 2300 BC), the world’s first author known by name, who wielded considerable religious and political power. Displaying a spectacular collection of her texts alongside other works made circa 3400–2000 BC, She Who Wrote celebrates Enheduanna’s poetry and her legacy as an author, priestess, and woman while bearing testament to women’s diverse roles in religious, social, economic, and political contexts—as goddesses, priestesses, worshippers, mothers, workers, and rulers. 

Fragment of a vessel with frontal image of goddess, Mesopotamia, Sumerian Early Dynastic IIIb period, ca. 2400 BC. Cuneiform inscription in Sumerian basalt, 9 7/8 × 7 5/16 × 1 9/16 in. (25.1 × 18.6 × 4 cm). Staatliche Museen zu Berlin, Vorderasiatisches Museum; VA 07248, acquired in 1914–15 

Enheduanna received her name, which means in Sumerian “high priestess, ornament of heaven”, upon her appointment to the temple of the moon god in Ur, a city in southern Mesopotamia, in present-day Iraq. The daughter of the Akkadian king Sargon (ca. 2334–2279 BC), Enheduanna left an indelible mark on the world of literature by composing extraordinary works in Sumerian. Her poetry reflected her devotion to the goddess of sexual love and warfare—Inanna in Sumerian, Ishtar in Akkadian. Whereas much of ancient Mesopotamian literature is unattributed, Enheduanna introduced herself by name and included autobiographical details in several poems. Her passionate voice had a lasting impact in Mesopotamia, as her writings continued to be copied in scribal schools for centuries after she died. 

In addition to texts by Enheduanna, She Who Wrote: Enheduanna and Women of Mesopotamia, ca. 3400- 2000 B.C includes works referencing her name and image, as well as representations of women from the earliest Mesopotamian cities. These examples represent painstaking artistry and stylistic variety, often combining a delicate naturalism with expressive stylization. These works of art have withstood millennia, lending us insight into an often-overlooked aspect of an ancient patriarchal society: womanhood.

Highlights in the exhibition include Fragment of a vessel with frontal image of goddess from the Early Dynastic IIIb period (ca. 2400 BC). This vessel fragment shows one of the first images of an anthropomorphic goddess created in Mesopotamia. The divine nature of the figure is expressed by the horned crown with feathers (or fronds) and an animal head, as well as by the vegetal elements above her shoulders. The goddess stares directly at the viewer, exuding power and authority. Her voluminous hair and the cluster of dates in her right hand depict her as a deity of fertility and abundance. 

Cylinder seal (modern impression) with goddesses Ninishkun and Ishtar,Mesopotamia, Akkadian, Akkadian period (ca. 2334–2154 BC), Cuneiforminscription: To the deity Niniškun, Ilaknuid, [seal]-cutter, presented (this),Limestone. The Oriental Institute of the University of Chicago, acquired 1947;A27903. 

Also included is Queen Puabi’s funerary ensemble, found during the excavation of her tomb in 1927. The ensemble is a feast for the eyes, with its vibrant colors, precious materials, and skilled artisanship. Several wreaths formed of floral and vegetal motifs rested on Puabi’s forehead, with ribbons of thinly hammered gold circling her voluminous hair and gold coils framing her face. At the crown of her head sits a large gold comb, featuring seven delicately curving flowers; large lunate earrings dangled from her ears. A choker with a central rosette sits against her neck, and a profusion of carnelian, lapis lazuli, and gold beads covers her chest, strung in rhythmic patterns. Finally, a belt of beads with a fringe of disks rests against Puabi’s hips. 

The exhibition also includes the Disk of Enheduanna from the Akkadian period, ca. 2300 BC. The partially preserved inscription on one side of this disk was recovered from a copy on an Old Babylonian (ca. 1894–1595 BC) tablet, recorded hundreds of years after the disk’s dedication by Enheduanna. The scene carved on the opposite side shows an open-air sacred precinct with

The exhibition also includes the Disk of Enheduanna from the Akkadian period, ca. 2300 BC. The partially preserved inscription on one side of this disk was recovered from a copy on an Old Babylonian (ca. 1894–1595 BC) tablet, recorded hundreds of years after the disk’s dedication by Enheduanna. The scene carved on the opposite side shows an open-air sacred precinct with a multistory edifice at left. Enheduanna occupies the center, depicted slightly larger than her attendants to reflect her status. Two priests behind her carry ritual paraphernalia; the one in front of her pours a libation on an altar. Enheduanna wears a tiered, flounced garment and a headdress in the form of a circlet, both of which became canonical for her successors. 

The Morgan’s Director, Colin B. Bailey, said, “After unavoidable delays due to the pandemic, we are delighted to be cooperating with colleagues from museums around the world, who have remained steadfast in their commitment to assist the Morgan in presenting this groundbreaking exhibition. Enheduanna’s legacy is multifaceted, and the Morgan is honored to present her story to a new generation of visitors.” 

The exhibition is curated by Sidney Babcock, Jeannette and Jonathan Rosen Curator and Department Head of Ancient Western Asian Seals and Tablets at the Morgan and co-curated by Erhan Tamur, Curatorial Research Associate for the Department. Babcock said, “Enheduanna is nothing less than the first known author in history. That she is not better known is something this exhibition hopes to remedy. The images of women from this period, presented here for the first time as a group, have often been overlooked. It is time to take a closer look at the extraordinary artistry of these images, as well as the way in which they reflect the contributions of women at the beginning of history. Preparing for this exhibition during the pandemic has been Preparing for this exhibition during the pandemic has been a challenge. I am deeply grateful to my colleagues at the Morgan and at the many national and international lending institutions for their enthusiastic support for this groundbreaking effort.” 

An array of engaging public programs will accompany the exhibition, including scholarly talks; a theatrical reading with live music; gallery tours and talks for adults and school children; and the family workshop "Signed, Sealed, Delivered: Cylinder Seal Family Workshop." A Family Guide will be available onsite and online. For addition information and updates visit: themorgan.org/program

Climate change and civil unrest among the ancient Maya

An extended period of turmoil in the prehistoric Maya city of Mayapan, in the Yucatan region of Mexico, was marked by population declines, political rivalries and civil conflict. Between 1441 and 1461 CE the strife reached an unfortunate crescendo -- the complete institutional collapse and abandonment of the city. This all occurred during a protracted drought.

Coincidence? Not likely, finds new research by anthropologist and professor Douglas Kennett of UC Santa Barbara.

Writing in the journal Nature Communications, lead author Kennett and collaborators in the fields of archaeology, history, geography and earth science suggest that drought may in fact have stoked the civil conflict that begat violence, which in turn led to the institutional instabilities that precipitated Mayapan's collapse. This transdisciplinary work, the researchers said, "highlights the importance of understanding the complex relationships between natural and social systems, especially when evaluating the role of climate change in exacerbating internal political tensions and factionalism in areas where drought leads to food insecurity."

"We found complex relationships between climate change and societal stability/instability on the regional level," Kennett said in an interview. "Drought-induced civil conflict had a devastating local impact on the integrity of Mayapan's state institutions that were designed to keep social order. However, the fragmentation of populations at Mayapan resulted in population and societal reorganization that was highly resilient for a hundred years until the Spanish arrived on the shores of the Yucatan."

The researchers examined archaeological and historical data from Mayapan, including isotope records, radiocarbon data and DNA sequences from human remains, to document in particular an interval of unrest between 1400 and 1450 CE. They then used regional sources of climatic data and combined it with a newer, local record of drought from cave deposits beneath the city, Kennett explained.

"Existing factional tensions that developed between rival groups were a key societal vulnerability in the context of extended droughts during this interval," Kennett said. "Pain, suffering and death resulted from institutional instabilities at Mayapan and the population fragmented and moved back to their homelands elsewhere in the region."

The vulnerabilities revealed in the data, the researchers found, were rooted in Maya reliance on rain-fed maize agriculture, a lack of centralized, long-term grain storage, minimal investments in irrigation and a sociopolitical system led by elite families with competing political interests.

Indeed the authors argue that "long-term, climate-caused hardships provoked restive tensions that were fanned by political actors whose actions ultimately culminated in political violence more than once at Mayapan."

Yet significantly, a network of small Maya states also proved to be resilient after the collapse at Mayapan, in part by migrating across the region to towns that were still thriving. Despite decentralization, trade impacts, political upheaval and other challenges, the paper notes, they adapted and persisted into the early 16th century. It all points to the complexity of human responses drought on the Yucatan Peninsula at that time -- an important consideration for the future as well as the past.

"Our study demonstrates that the convergence of information from multiple scientific disciplines helps us explore big and highly relevant questions," Kennett said, "like the potential impact of climate change on society and other questions with enormous social implications.

"Climate change worries me, particularly here in the western U.S., but it is really the complexities of societal change in response to climatic perturbations that worry me the most," he added. "The archaeological and historical records provide lessons from the past, and we also have so much more information about our Earth's climate and the potential vulnerabilities in our own sociopolitical systems."