Italian sailors knew of America 150 years before Christopher Columbus, new analysis of ancient documents suggests

 New analysis of ancient writings suggests that sailors from the Italian hometown of Christopher Columbus knew of America 150 years before its renowned 'discovery'.

Transcribing and detailing a, circa, 1345 document by a Milanese friar, Galvaneus Flamma, Medieval Latin literature expert Professor Paolo Chiesa has made an "astonishing" discovery of an "exceptional" passage referring to an area we know today as North America.

According to Chiesa, the ancient essay -- first discovered in 2013 -- suggests that sailors from Genoa were already aware of this land, recognizable as 'Markland'/ 'Marckalada' -- mentioned by some Icelandic sources and identified by scholars as part of the Atlantic coast of North America (usually assumed to be Labrador or Newfoundland).

Published in the peer-reviewed journal Terrae Incognitae, the discovery comes ahead of Columbus Day 2021, alternatively celebrated as Indigenous Peoples' Day across many states in the US. The findings add more fuel to the fire for the continuing question of 'what, exactly, did Columbus expect to find when he set out across the ocean?' and come following a period in which his statues have been beheaded, covered with red paint, lassoed around the head and pulled down, set on fire and thrown into a lake.

"We are in the presence of the first reference to the American continent, albeit in an embryonic form, in the Mediterranean area," states Professor Chiesa, from the Department of Literary Studies, Philology and Linguistics at the University of Milan.

Galvaneus was a Dominican friar who lived in Milan and was connected to a family which held at the lordship of the city.

He wrote several literary works in Latin, mainly on historical subjects. His testimony is valuable for information on Milanese contemporary facts, about which he has first-hand knowledge.

Cronica universalis, which is analyzed here by Chiesa, is thought to be one of his later works -- perhaps the last one -- and was left unfinished and unperfected. It aims to detail the history of the whole world, from 'Creation' to when it was published.

In translating and analysing the document, Professor Chiesa demonstrates how Genoa would have been a "gateway" for news, and how Galvaneus appears to hear, informally, of seafarers' rumours about lands to the extreme north-west for eventual commercial benefit -- as well as information about Greenland, which he details accurately (for knowledge of the time).

"These rumours were too vague to find consistency in cartographic or scholarly representations," the professor states, as he explains why Marckalada wasn't classified as a new land at the time.

Regardless though, Chiesa states, Cronica universalis "brings unprecedented evidence to the speculation that news about the American continent, derived from Nordic sources, circulated in Italy one and half centuries before Columbus."

He adds: "What makes the passage (about Marckalada) exceptional is its geographical provenance: not the Nordic area, as in the case of the other mentions, but northern Italy.

"The Marckalada described by Galvaneus is 'rich in trees', not unlike the wooded Markland of the Grœnlendinga Saga, and animals live there.

"These details could be standard, as distinctive of any good land; but they are not trivial, because the common feature of northern regions is to be bleak and barren, as actually Greenland is in Galvaneus's account, or as Iceland is described by Adam of Bremen."

Overall, Professor Chiesa says, we should "trust" Cronica universalis as throughout the document Galvaneus declares where he has heard of oral stories, and backs his claims with elements drawn from accounts (legendary or real) belonging to previous traditions on different lands, blended together and reassigned to a specific place.

"I do not see any reason to disbelieve him," states Professor Chiesa, who adds, "it has long been noticed that the fourteenth-century portolan (nautical) charts drawn in Genoa and in Catalonia offer a more advanced geographical representation of the north, which could be achieved through direct contacts with those regions.

"These notions about the north-west are likely to have come to Genoa through the shipping routes to the British Isles and to the continental coasts of the North Sea.

"We have no evidence that Italian or Catalan seafarers ever reached Iceland or Greenland at that time, but they were certainly able to acquire from northern European merchant goods of that origin to be transported to the Mediterranean area.

"The marinarii mentioned by Galvaneus can fit into this dynamic: the Genoese might have brought back to their city scattered news about these lands, some real and some fanciful, that they heard in the northern harbors from Scottish, British, Danish, Norwegian sailors with whom they were trading."

Cronica universalis, written in Latin, is still unpublished; however, an edition is planned, in the context of a scholarly and educational program promoted by the University of Milan.

Roman noblewoman’s tomb reveals secrets of ancient concrete resilience

Over time, concrete cracks and crumbles. Well, most concrete cracks and crumbles. Structures built in ancient Rome are still standing, exhibiting remarkable durability despite conditions that would devastate modern concrete.

One of these structures is the large cylindrical tomb of first-century noblewoman Caecilia Metella. New research shows that the quality of the concrete of her tomb may exceed that of her male contemporaries' monuments because of the volcanic aggregate the builders chose and the unusual chemical interactions with rain and groundwater with that aggregate over two millennia.

"The construction of this very innovative and robust monument and landmark on the Via Appia Antica indicates that she was held in high respect," says Marie Jackson, research associate professor of geology and geophysics at the University of Utah, "and the concrete fabric 2,050 years later reflects a strong and resilient presence."

The research is published in the Journal of the American Ceramic Society and is funded in part by the U.S. Department of Energy ARPA-e "Extreme Durability of Cementitious Materials" program.

Who was Caecilia Metella?

The tomb of Caecilia Metella is a landmark on the Via Appia Antica, an ancient Roman road also known as the Appian Way. It consists of a drum-shaped tower that sits on a square base, in total about 70 feet (21 m) tall and 100 feet (29 m) in diameter. Built about 30 BCE, at the transformation of the Roman Republic to the Roman Empire, led by Emperor Augustus, in 27 BCE, the tomb is considered one of the best-preserved monuments on the Appian Way (a castle attached to the tomb was built in the 14th century).

Caecilia herself was a member of a wealthy family, the daughter of a Roman consul. She married into the family of Marcus Lincius Crassus, a Roman general and statesman who formed a famous triumvirate alliance with Julius Caesar and Pompey.

Not much more is known about Caecilia's life, but the enduring magnitude of her tomb has caught the attention of visitors for centuries, including Lord Byron who wrote of the tomb in "Childe Harold's Pilgrimage" in the early 1800s. After describing the fortress-like structure, Byron asks:

"What was this tower of strength? within its cave

What treasure lay so lock'd, so hid? -- A woman's grave."

Jackson visited the tomb in 2006 with archaeologist Dottoressa Lisa Gianmichele and with a permit from the Soprintendenza Archeologia di Roma to collect small samples of the mortar for analysis.

"It was a very warm day in June," she says, "yet when we descended the steps to the sepulchral corridor the air became very cool and moist." She notes the compact, cohesive, nearly perfectly preserved brick masonry walls and the nearly water-saturated volcanic rock outcrop in the sub-structure.

"The atmosphere was very tranquil," she adds, "except for the fluttering of pigeons in the open center of the circular structure."

What is Roman concrete?

Before diving into the particulars, let's get oriented to the terminology of concrete. Walk along most any sidewalk and you'll see that concrete is made of an aggregate (rock sands and gravels) and a cement binder. The cement in a modern sidewalk is likely Portland cement, produced by heating limestone and clay minerals in a kiln to form clinker, grinding the clinker and adding a small amount of gypsum.

The tomb is an example of the refined technologies of concrete construction in late Republican Rome that contain no cement. The technologies were described by the architect Vitruvius during the period when the tomb of Caecilia Metella was under construction. Building thick walls of coarse brick or volcanic rock aggregate bound with mortar made with hydrated lime and volcanic tephra (porous fragments of glass and crystals from explosive eruptions), would result in structures that "over a long passage of time do not fall into ruins."

Vitruvius' words are proven true by the many Roman structures standing today, including Markets of Trajan (built between 100 and 110 CE, more than a century after the tomb) and marine structures like piers and breakwaters, which Jackson and her colleagues have also studied.

What the ancient Romans couldn't have known, though, is how crystals of the mineral leucite, which is rich in potassium, in the volcanic tephra aggregate would dissolve over time to beneficially remodel and reorganize the cohesion of the concrete.

To understand the mineral structure of the concrete, Jackson teamed up with researchers Linda Seymour and Admir Masic from the Massachusetts Institute of Technology and Nobumichi Tamura at the Lawrence Berkeley National Laboratory. They delved into the microstructure of the concrete with an array of powerful scientific tools.

"Samples such as ancient mortar are highly heterogeneous and complex, made of a mixture of different crystalline phases with grain sizes ranging from a few micrometers down to a few nanometers," says Tamura, who conducted analyses using the Advanced Light Source beamline 12.3.2. To identify the different minerals in the sample, as well as their orientation, he says, you need an instrument like the microdiffraction beamline at the Advanced Light Source that produces a "micron size, extremely bright and energetic pencil X-ray beam that can penetrate through the entire thickness of the samples, making it a perfect tool for such a study."

Seymour, who participated in this study as a Ph.D. student at MIT and is now a project consultant with engineering firm Simpson, Gumpertz & Heger, conducted additional analyses on the samples.

"Each of the tools that we used added a clue to the processes in the mortar," she says. Scanning electron microscopy showed the micro-structures of mortar building blocks at the micron scale. Energy-dispersive X-ray spectrometry showed the elements comprising each of those building blocks. "This information allows us to explore different areas in the mortar quickly, and we could pick out building blocks related to our questions," she says. The trick, she adds, is to precisely hit the same building block target with each instrument when that target is only about the width of a hair.

Why is the concrete at Caecilia's tomb so unique?

In the thick concrete walls of Caecilia Metella's tomb, a mortar that contains volcanic tephra from the nearby Pozzolane Rosse pyroclastic flow (a dense mass of hot tephra and gases ejected explosively from the nearby Alban Hills volcano) binds large chunks of brick and lava aggregate. It is much the same mortar used in the walls of the Markets of Trajan 120 years later.

In previous analysis of the Markets of Trajan mortar, Jackson, Tamura and their colleagues explored the "glue" of the mortar, a building block called the C-A-S-H binding phase (calcium-aluminum-silicate-hydrate), along with a mineral called strätlingite. The strätlingite crystals block the propagation of microcracks in the mortar, preventing them from linking together and fracturing the concrete structure.

But the tephra the Romans used for the Caecilia Metella mortar was more abundant in potassium-rich leucite. Centuries of rainwater and groundwater percolating through the tomb's walls dissolved the leucite and released the potassium into the mortar. In modern concrete, such a flood of potassium would create expansive gels that would cause microcracking and eventual spalling and deterioration of the structure.

In the tomb, however, the potassium dissolved and reconfigured the C-A-S-H binding phase. Seymour says that X-ray microdiffraction and Raman spectroscopy techniques allowed them to explore how the mortar had changed. "We saw C-A-S-H domains that were intact after 2,050 years and some that were splitting, wispy or otherwise different in morphology," she says. X-ray microdiffraction, in particular, allowed an analysis of the wispy domains down to their atomic structure. "We see that the wispy domains are taking on a nano-crystalline nature," she says.

The remodeled domains "evidently create robust components of cohesion in the concrete," says Jackson. In these structures, unlike in the Markets of Trajan, there's much less strätlingite formed.

Stefano Roascio, the archaeologist in charge of the tomb, notes that the study has a great deal of relevance to understanding other ancient and historic concrete structures that use Pozzolane Rosse aggregate.

Admir Masic, associate professor of civil and environmental engineering at MIT, says that the interface between the aggregates and the mortar of any concrete is fundamental to the structure's durability. In modern concrete, he says, the alkali-silica reactions that form expansive gels may compromise the interfaces of even the most hardened concrete.

"It turns out that the interfacial zones in the ancient Roman concrete of the tomb of Caecilia Metella are constantly evolving through long-term remodeling," he says. "These remodeling processes reinforce interfacial zones and potentially contribute to improved mechanical performance and resistance to failure of the ancient material."

Can we recreate that effect today?

Jackson and her colleagues are working to replicate some of the Romans' successes in modern concretes, specifically in a U.S. Department of Energy ARPA-e project to encourage similar beneficially reactive aggregates in concretes that use engineered cellular magmatics in place of the tephra of the ancient Roman structures. The objective, according to ARPA-e, is that a Roman-like concrete could reduce the energy emissions of concrete production and installation by 85% and improve the 50-year lifespan of modern marine concretes four-fold.

"Focusing on designing modern concretes with constantly reinforcing interfacial zones might provide us with yet another strategy to improve the durability of modern construction materials," Masic says. "Doing this through the integration of time-proven 'Roman wisdom' provides a sustainable strategy that could improve the longevity of our modern solutions by orders of magnitude."

Early human activities impacted Earth’s atmosphere more than previously known

 Several years ago, while analyzing ice core samples from Antarctica’s James Ross Island, scientists Joe McConnell, Ph.D., and Nathan Chellman, Ph.D., from DRI, and Robert Mulvaney, Ph.D., from the British Antarctic Survey noticed something unusual: a substantial increase in levels of black carbon that began around the year 1300 and continued to the modern day.

Black carbon, commonly referred to as soot, is a light-absorbing particle that comes from combustion sources such as biomass burning (e.g. forest fires) and, more recently, fossil fuel combustion. Working in collaboration with an international team of scientists from the United Kingdom, Austria, Norway, Germany, Australia, Argentina, and the U.S., McConnell, Chellman, and Mulvaney set out to uncover the origins of the unexpected increase in black carbon captured in the Antarctic ice.

The team’s findings, which published this week in Nature, point to an unlikely source: ancient Māori land-burning practices in New Zealand, conducted at a scale that impacted the atmosphere across much of the Southern Hemisphere and dwarfed other preindustrial emissions in the region during the past 2,000 years.

“The idea that humans at this time in history caused such a significant change in atmospheric black carbon through their land clearing activities is quite surprising,” said McConnell, research professor of hydrology at DRI who designed and led the study. “We used to think that if you went back a few hundred years you’d be looking at a pristine, pre-industrial world, but it’s clear from this study that humans have been impacting the environment over the Southern Ocean and the Antarctica Peninsula for at least the last 700 years.”

Tracing the black carbon to its source

To identify the source of the black carbon, the study team analyzed an array of six ice cores collected from James Ross Island and continental Antarctica using DRI’s unique continuous ice-core analytical system. The method used to analyze black carbon in ice was first developed in McConnell’s lab in 2007.

While the ice core from James Ross Island showed a notable increase in black carbon beginning around the year 1300, with levels tripling over the 700 years that followed and peaking during the 16th and 17th centuries, black carbon levels at sites in continental Antarctica during the same period of time stayed relatively stable.

Andreas Stohl, Ph.D., of the University of Vienna led atmospheric model simulations of the transport and deposition of black carbon around the Southern Hemisphere that supported the findings.

“From our models and the deposition pattern over Antarctica seen in the ice, it is clear that Patagonia, Tasmania, and New Zealand were the most likely points of origin of the increased black carbon emissions starting about 1300,” said Stohl.

After consulting paleofire records from each of the three regions, only one viable possibility remained: New Zealand, where charcoal records showed a major increase in fire activity beginning about the year 1300. This date also coincided with the estimated arrival, colonization, and subsequent burning of much of New Zealand’s forested areas by the Māori people.

This was a surprising conclusion, given New Zealand’s relatively small land area and the distance (nearly 4,500 miles), that smoke would have travelled to reach the ice core site on James Ross Island.

“Compared to natural burning in places like the Amazon, or Southern Africa, or Australia, you wouldn’t expect Māori burning in New Zealand to have a big impact, but it does over the Southern Ocean and the Antarctic Peninsula,” said Chellman, postdoctoral fellow at DRI. “Being able to use ice core records to show impacts on atmospheric chemistry that reached across the entire Southern Ocean, and being able to attribute that to the Māori arrival and settlement of New Zealand 700 years ago was really amazing.”

Research impacts

The study findings are important for a number of reasons. First, the results have important implications for our understanding of Earth’s atmosphere and climate. Modern climate models rely on accurate information about past climate to make projections for the future, especially on emissions and concentrations of light-absorbing black carbon linked to Earth’s radiative balance. Although it is often assumed that human impacts during preindustrial times were negligible compared to background or natural burning, this study provides new evidence that emissions from human-related burning have impacted Earth’s atmosphere and possibly its climate far earlier, and at scales far larger, than previously imagined.

Second, fallout from biomass burning is rich in micronutrients such as iron. Phytoplankton growth in much of the Southern Ocean is nutrient-limited so the increased fallout from Māori burning probably resulted in centuries of enhanced phytoplankton growth in large areas of the Southern Hemisphere.

Third, the results refine what is known about the timing of the arrival of the Māori in New Zealand, one of the last habitable places on earth to be colonized by humans. Māori arrival dates based on radiocarbon dates vary from the 13th to 14th century, but the more precise dating made possible by the ice core records pinpoints the start of large scale burning by early Māori in New Zealand to 1297, with an uncertainty of 30 years.

“From this study and other previous work our team has done such as on 2,000-year old lead pollution in the Arctic from ancient Rome, it is clear that ice core records are very valuable for learning about past human impacts on the environment,” McConnell said. “Even the most remote parts of Earth were not necessarily pristine in preindustrial times.”

Additional information:

The full study, Hemispheric black carbon increase after 13th C Māori arrival in New Zealand, is available from Nature: https://www.nature.com/articles/s41586-021-03858-9 

Multiple individuals are buried in the Tomb of Nestor’s Cup

 

IMAGE: THE CUP IS ON PERMANENT DISPLAY AT THE MUSEO ARCHEOLOGICO NAZIONALE DI VILLA ARBUSTO, LACCO AMENO (ISCHIA ISLAND). THE METRIC INSCRIPTION, PARTIALLY IN HEXAMETER VERSES, TRANSLATES ROUGHLY TO ‘I AM NESTOR’S CUP, GOOD TO DRINK FROM. WHOEVER DRINKS THIS CUP EMPTY, STRAIGHTAWAY DESIRE FOR BEAUTIFUL-CROWNED APHRODITE WILL SEIZE HIM’ (PICTURE FROM SOPRINTENDENZA ARCHEOLOGIA, BELLE ARTI E PAESAGGIO PER L’AREA METROPOLITANA DI NAPOLI). view more 

CREDIT: GIGANTE ET AL., 2021, PLOS ONE, CC-BY 4.0 (HTTPS://CREATIVECOMMONS.ORG/LICENSES/BY/4.0/)

The Tomb of Nestor’s Cup, a famous burial in Italy, contains not one deceased individual, but several, according to a study published October 6, 2021 in the open-access journal PLOS ONE by Melania Gigante of the University of Padua, Italy and colleagues.

The Tomb of Nestor’s Cup is considered one of the most intriguing discoveries in Mediterranean pre-classic archaeology. Formally designated Cremation 168 and dating to the 8th century BCE, this tomb is one of hundreds uncovered in the Italian site of Pithekoussai. The tomb contains cremated bones, a rich set of grave goods, and the exceptional eponymous cup featuring one of the earliest known Greek inscriptions. Previous research suggested that the tomb’s remains belong to a single young human, but the question of “Who’s buried with Nestor’s Cup?” remains a puzzle.

In this study, Gigante and colleagues performed detailed analyses on the shape (morphology) and tissues (histology and histomorphometry) of the 195 burnt bone fragments in the tomb. They determined that only about 130 of these fragments are human, while at least 45 belong to animals, including goats and possibly dogs. Among the human remains, the researchers identified bone tissue characteristic of varying life stages, indicating at least three individuals of different ages. This is the first evidence of multiple individuals (and non-humans) among the remains in the Tomb of Nestor’s Cup.

These results raise even more questions about the mysterious tomb. This study was unable to determine details about the humans among the remains, including their age at death or why they were buried with the cup. As for the animal remains, the researchers suspect these might have been included as food or companions for the deceased. This study represents the usefulness of histological data for examining burial sites. Further such study might unravel the puzzles surrounding the formation of this tomb and its famous cup.

The authors add: “More than fifty years after its discovery, the Tomb of Nestor’s Cup (Ischia Island, in the Gulf of Naples, Italy), widely considered one of the most important archaeological findings of Pre-Classical Mediterranean Archeology, is back in the news. Our research rewrites the history and the previous archaeological interpretation of the Tomb, throwing new light on funeral practices, culture and society of the Greek immigrants in the ancient West Mediterranean. Our research, which combines the great work of archaeological interpretation to specific know-how in histology and advanced analysis on cremated remains, marked a double goal: firstly, we were able to reconstruct the osteobiography of the individuals from Tomb 168 at Pithekoussai (the first settlement of Greek colonist at the dawn of Magna Graecia in Italy), answering the thorny question: who/what was buried with Nestor’s Cup? Secondly, we are sure that our study can be a new methodological step toward the reconstruction of the life-history of people in ancient times, even in case of poor preservation and/or complexity of the skeletal assemblage.”

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Line and hook fishing techniques in Epipaleolithic Israel

 

IMAGE: A RECONSTRUCTION OF A HOOK & SMALL GROOVED PEBBLE ON A LINE. NOTE THE SOPHISTICATED KNOT. view more 

CREDIT: EMANUELA CRISTIANI, CC-BY 4.0 (HTTPS://CREATIVECOMMONS.ORG/LICENSES/BY/4.0/)

Humans in the Middle East were using complex fishing tools and techniques by 12,000 years ago, according to a study published October 6, 2021 in the open-access journal PLOS ONE by Antonella Pedergnana of the Archaeological Research Centre and Museum for Human Behavioural Evolution in Mainz, Germany and colleagues.

Fish have long been an important part of human diets, but it is challenging to study the history of the technology humans have used to acquire fish, in part because early fishing gear was made from perishable materials like wood and plant fibers. In this study, Pedergnana and colleagues examined a collection of fishing hooks and stones from the archaeological site of Jordan River Dureijat in northern Israel, at least 12,000 years old.

The team analyzed the shape and residues of 19 bone fish hooks, as well as six grooved pebbles that appear to have been used as sinkers, altogether one of the largest collections of early fishing technology. Plant fiber residue on the hooks and stones indicate the use of fishing line, and the wide variety of hook shapes, including multiple arrangements of barbs and multiple methods for attaching hook to line, reflect their utility for catching a variety of fish. Additionally, grooved lines and fiber residues on the bends of some hooks indicate the use of artificial lures.

This study identifies some of the earliest evidence of complex fishing technology. The use of lures and a wide variety of hook shapes suggests the humans of this time were not only hunting a broad spectrum of fish, but also that they had profound knowledge of fish behavior and ecology. These innovations coincide with broader patterns in human subsistence evolution which mark the beginning of the transition to agriculture in this region of the world.

The authors add: “Except for the use of metal and plastic, modern fishing has not invented anything new since the Natufian. A look at the JRD fishing gear reveals that all fishing techniques and knowledge already existed some 13,000 years ago. The finds highlight the importance of aquatic resources for the emergence of sedentism and the Neolithic life ways in the Levant.”

The colonization of the Azores began 700 years prior to the Portuguese arrival

The human occupation of the Azores Islands began 700 years earlier than the onset of Portuguese settlement of the island, which as historical documents indicate, was in the 15thcentury. This is the main conclusion of new research conducted by an international multidisciplinary team of scientists with the participation of the CSIC. The study published in the journal PNAS, reconstructs when, how, and under which climatic conditions the islands were colonized, in addition to the impacts of the first human settlements on the ecosystems, by analyzing sediment cores recovered from several lakes on the islands. The authors of the study suggest that the first settlers came from northern Europe, and that their arrival occurred in conjunction with favorable climatic conditions to allow sailing towards these volcanic islands, which are located some 1,450 km from the European coast.

Until recently, the consensus had been that the Azores were not colonized until the arrival of the Portuguese while searching for new routes to Asia. According to historical sources, the Portuguese first arrived at Santa Maria Island in 1427 CE, and in 1452 CE they reached the Flores Corvo islands. However, the present study determines that humans first occupied these islands at the end of the Early Middle Ages, between 700 and 850 CE.

According to Santiago Giralt, a researcher at Geosciences Barcelona (Geo3BCN-CSIC) and co-author of the article, “this study highlights that, even with abundant available historical information allowing us to have a very accurate picture of the past, it is necessary to foster interdisciplinary research, among the Humanities and Natural Sciences, to fully understand our history.”

By using geological, chemical, physical, and biological analytical techniques, the researchers dated and characterized five sediment cores recovered from the lakes of the Sao Miguel, Pico, Terceira, Flores, and Corvo islands. The researchers found both sterols—which make up a fraction of the organic matter abundant in mammal feces—as well as coprophilous fungal spores in the sediment samples, which were used as indicators of human activity related to the introduction of livestock.

“Fecal sterols and stanols are produced in great abundance in the intestinal tracks of mammals and are well-preserved in lake sediments, providing a unique and unambiguous tracer of the presence of large mammals during past time intervals”, said Timothy Shanahang, researcher from the University of Texas and co-author of the study. “Furthermore, the compounds (such as coprostanol and stigmastanol) produced in the guts of humans and livestock differ, allowing us to distinguish between them”.

“Due to its geographical location, in the middle of the Atlantic Ocean, large mammals were not present in the Azores Islands”, said Giralt. “Hence, finding coprostanol in the sediments can be attributed to human presence, and finding stigmastanol can be attributed to ruminants, such as cows, sheep, or goats”.

Pollen, fossils, and charcoal analyses

Researchers also used other proxies, such as pollen, plant macrofossils, or charcoal particles, to investigate the human impacts on the island's environment “As we demonstrate in this work, early human settlement on the islands led to a profound environmental and ecological disturbance. Although official documentary sources described the Azores as heavily forested and pristine, this study highlights the challenge in relying on the historical record to identify relative states of ecosystems or landscape disturbances.”, said Pedro Raposeiro, a researcher from the University of the Azores and lead author of the study.

The researchers also conducted climate simulations to better understand the climate conditions during the initial occupation of the archipelago. According to these models, and previously published archeological and genetic studies, the authors of the study suggest that the Norse were most likely the earliest settlers of the Azores. These explorers found favorable climatic conditions, which permitted them to sail towards the archipelago during a period of anomalous northerly, and weakened westerly winds, facilitating the arrival from northern Europe.

 “Because of the Earth’s rotation, westerly winds are dominant in the Atlantic Ocean, which are reinforced or weakened depending on the NAO (North Atlantic Oscillation), the main climate mode that controls the atmospheric circulation in the northern hemisphere. The NAO is modulated at the same time by the East Atlantic pattern, which controls the intensity of the northerly winds”, explains Santiago Giralt.

Late persistence of human ancestors at the margins of the monsoon in India

Peer-Reviewed Publication

 

IMAGE: A HANDAXE FROM THE THAR DESERT, WHERE ACHEULEAN POPULATIONS PERSISTED UNTIL AT LEAST 177 THOUSAND YEARS AGO view more 

CREDIT: JIMBOB BLINKHORN

The longest lasting tool-making tradition in prehistory, known as the Acheulean, appears more than 1.5 million years ago in Africa and 1.2 million years ago in India, and mainly consists of stone handaxes and cleavers (Figure 1). New research led by the Max Planck Institute for the Science of Human History has re-examined a key Acheulean site at the margins of the monsoon zone in the Thar Desert, Rajasthan, revealing the presence of Acheulean populations until about 177,000 years ago, shortly before the earliest expansions of Homo sapiens across Asia.

The timing and route of the earliest expansions of our own species across Asia have been the focus of considerable debate but a growing body of evidence indicates Homo sapiens interacted with numerous populations of our closest evolutionary cousins. Identifying where these different populations met is critical to revealing the human and cultural landscape encountered by the earliest members of our species to expand beyond Africa. Although fossils of ancient human populations are extremely rare in South Asia, changes in the stone tool kits they made, used, and left behind can help resolve when and where these encounters may have occurred.

The youngest Acheulean in western India

In a paper published in Scientific Reports, an international team of researchers led by the Max Planck Institute for the Science of Human History report the relatively recent occupation of the site of Singi Talav (Rajasthan, India) by Acheulean populations up to 177,000 years ago (Figure 2). The site was once thought to be amongst the oldest Acheulean sites in India, but now appears to be one of the youngest. Indeed, these dates show the persistence of Acheulean populations in the Thar Desert after their disappearance in eastern Africa around 214,000 years ago and Arabia 190,000 years ago. This result supports the late persistence of Acheulean populations in India, where previous research has shown their presence as recently as 130,000 years ago.

The site of Singi Talav, set on a lakeside close to the modern town of Didwana at the edge of the Thar Desert, was first excavated in the early 1980's, revealing multiple stone tool assemblages (Figure 3). The largest assemblage shows a focus on the production of stone handaxes and cleavers that are typical of the Acheulean. However, the techniques needed to accurately date these assemblages were not available at the time of their discovery. Since then, a range of sites have been examined that constrain the chronology of Acheulean occupations in India, but the ecological settings of the sites remains poorly known.

"The lakeside setting has ideal preservation conditions for an archaeological site, enabling us to return 30 years after the first excavation and readily re-identify the main occupation horizons again," says Dr Jimbob Blinkhorn of the Max Planck Institute for the Science of Human History, the lead author of the study. "We've applied a range of modern methods to re-examine this critical site, including new approaches to directly date the occupation horizons and to reveal the vegetation in the landscape that Acheulean populations inhabited."

The researchers used luminescence methods to directly date the sediment horizons occupied by ancient human populations. These methods rely on the ability of minerals like quartz and feldspar to store and release energy induced by natural radioactivity, allowing scientists to determine the last time sediments were exposed to light. 

"Ours is the first study to directly date the occupation horizons at Singi Talav, enabling us to understand both when ancient humans lived here and created the stone tool assemblages, and how these occupations compare with other sites across the region," adds Dr Julie Durcan of the University of Oxford.

At the margins of the monsoon

The Thar Desert sits at the western edge of the modern Indian summer monsoon system, and its habitability to ancient human populations likely fluctuated significantly. The researchers examined plant microfossils, known as phytoliths, as well as features of soil geochemistry to reveal the ecology of the site at the time the Acheulean toolkits were produced.

"This is the first time the ecology of an Acheulean site in India has been studied using these methods, revealing the broader character of the landscape that these populations inhabited," says Prof Hema Achyuthan of Anna University, Chennai, who also participated in the original excavations at the site. "The results from the two methods we applied complement each other to reveal a landscape rich in the types of grasses that flourish during periods with enhanced summer monsoons."

With this data, the study illuminates the environmental conditions that allowed Acheulean populations to thrive at the margins of the monsoon in the Thar Desert until at least 177,000 years ago.

"This supports evidence from across the region indicating that India hosted the youngest populations using Acheulean toolkits across the world," adds Blinkhorn. "Critically, the late persistence of the Acheulean at Singi Talav and elsewhere in India directly precedes evidence for the appearance of our own species, Homo sapiens, as they expanded across Asia."

The Thar Desert likely presented a key ecological frontier for expanding populations of Homo sapiens moving eastwards as they first met the Indian monsoon system. The results of this study suggest that this may have also been a demographic and behavioural frontier - a potential zone in which Homo sapiens encountered another, closely related, human population.

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