Posts Tagged ‘Ancient civilizations’

First Harbor of Ancient Rome Rediscovered

Posted: December 15, 2012 by phaedrap1 in News
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Archaeologists have unearthed the great ancient monuments of Ostia, but the location of the harbour which supplied Rome with wheat remained to be discovered. Thanks to sedimentary cores, this ” lost ” harbour has eventually been located northwest of the city of Ostia, on the left bank of the mouth of the Tiber. Stratigraphy has revealed that at its foundation, between the 4th and 2nd century BC, the basin was deeper than 6.5 m, the depth of a seaport.

This research was carried out by a French-Italian team of the Maison de l’Orient et de la Méditerranée (CNRS / Université Lumière Lyon 2), the Ecole Française de Rome and Speciale per i Beni Soprintendenza Archeologici di Roma — Sede di Ostia* and will be published in the Chroniques des Mélanges de l’Ecole Française de Rome in December 2012.

According to ancient texts, Ostia was founded by Ancus Marcius, the 4th king of Rome. This new settlement is supposed to have aimed three goals: to give Rome an outlet to the sea, to ensure its supply of wheat and salt and finally, to prevent an enemy fleet to ascend the Tiber. Archeological excavations showed that the original urban core (castrum) dates back to the turn of the 4th and 3th centuries BC. Major ancient buildings and main roads were progressively revealed, but the location of the Ostia river mouth harbour remained unknown to this day. For some, it was considered as lost forever. Since the Renaissance, many attempts to locate the harbour of Ostia were undertaken without success. It was not until the 19th and 20th centuries that Italian archaeologists defined an area north-west of the city, near the Imperial Palace. At the turn of the century, archaeologists confirmed the probable location of the basin, in that zone, by using geomagnetic instruments. However there was still no consensus on the exact location of the port and the debate was still alive.

A French-Italian team led by Jean-Philippe Goiran, CNRS researcher, has tried to definitely verify the hypothetical location of the harbour, by using a new geological corer. This technology solves the problem of groundwater which makes this area rather difficult for archeologists to excavate beyond 2 m deep.

Two sediment cores have been extracted, showing a complete 12 m depth stratigraphy and the evolution of the harbour zone in 3 steps:

1 — The deepest stratum, before the foundation of Ostia, indicates that the sea was present in that area in the early 1st millennium BC.

2 — A middle layer, rich in grey silty-clay sediments, shows a typical harbour facies. According to calculations, the basin had a depth of 6.5 m at the beginning of its operation (dated between the 4th and 2d centuries BC). Previously considered as a river harbour that can only accommodate low draft boats, Ostia actually enjoyed a deep basin capable of receiving deep draft marine ships.

3 — Finally, the most recent stratum, composed of massive alluvium accumulations, shows the abandonment of the basin during the Roman imperial period. With radiocarbon dates, it is possible to deduce that a succession of major Tiber floods episodes of the Tiber finally came to seal the harbour of Ostia between the 2nd century BC and the 1st quarter of the 1st century AD (and this despite possible phases of dredging). At that time, the depth of the basin was less than 1 m and made any navigation impossible. It was then abandoned in favor of a new harbour complex built 3 km north of the Tiber mouth, called Portus. This alluvium layer fits with the geographer Strabo’s text (58 BC — 21/25 AD) who indicated the sealing of the harbour basin by sediments of the Tiber at that time (Geographica, 231-232).

The discovery of the river mouth harbour of Ostia, north of the city and west of the Imperial Palace, will help better understand the links between Ostia, its harbour and the ex-nihilo settling of Portus, initiated in 42 AD and completed in 64 AD under the reign of Nero. This gigantic 200 ha wide complex became the harbour of Rome and the largest ever built by the Romans in the Mediterranean.

Between the abandonment of the port of Ostia and the construction of Portus, researchers estimate that nearly 25 years have passed. Rome was the capital of the ancient Roman world and the first city to reach one million inhabitants. So how was it supplied with wheat during that period? The question arises now researchers.

*This work was also carried out in collaboration with the Maison Méditerranéenne des Sciences de l’Homme (CNRS / Aix-Marseille Université), the Universita Roma 3, the Institut Universitaire de France and received the support of the ANR (Agence Nationale de la Recherche).

Science News

Jade vulture.

A jade pendant of a vulture discovered at the Maya site of Tak’alik Ab’aj. (Tak’alik Ab’aj Archaeological Project / Associated Press / October 29, 2012)

By Thomas H. Maugh II Los Angeles TimesOctober 29, 2012, 11:27 a.m.

Guatemalan archaeologists have found the tomb of what may have been one of the Maya’s earliest rulers and perhaps its most influential. King K’utz Chman introduced many cultural features that eventually defined the Maya, including building pyramids instead of square structures and commissioning the production of carved sculptures that depicted the royal family. His grave is the most ancient royal Maya burial to be found and it contains a variety of carved jade objects indicating his wealth and status.

“He was the big chief,” archaeologist Miguel Orrego of the Guatemalan Instituto de Antropologia e Historia told Reuters. Chman was “the ruler who bridged the gap between Olmec and Maya cultures and initiated the slow transition to Maya rule.”

The tomb was found in June at the  site of Tak’alik Ab’aj, a large city in the Retalhuleu department of southwestern Guatemala, about 110 miles south of Guatemala City. Tak’alik Ab’aj is the Maya name, meaning “Standing Stone,” given to the site by scientists. Its ancient name may have been Kooja, meaning “Moon Halo.” The city flourished from about the 9th century BC through at least the 10th century and its residents traded heavily with other cities, some as far away as Teotihuacan in Mexico. It is one of the largest Maya sites along the Pacific Coast.

The newly discovered tomb contains no human bones, but carbon-dating of other organic materials indicates that it was constructed sometime between 770 and 510 BC. The Maya empire began to thrive around 400 BC as the Olmec empire faded.

Inside the tomb, the team found a variety of jade objects, including a necklace with a pendant carved in the shape of a vulture’s head. Such objects were generally the property of very powerful men and a symbol of great respect. Because of the necklace, the team named the king K’utz Chman, which translates roughly as “Grandfather Vulture.”

Other objects in the tomb included ceramic pots, ceramic dolls and jade beans.

“The richness of the artifacts tells us he was an important and powerful religious leader,” said archaeologist Christa Schieber of the institute. “He was very likely the person who began to make changes in the system and transition into the Maya world.”

Small bear figurines have led researchers on the trail of hitherto unknown pre-Inuit rituals, indicating that these people practiced a bear cult.

The headless bear figure was found lying with its neck against the back wall, as if it was diving into the fireplace This has led archaeologists to believe they are dealing with a hitherto unknown ritual practice. (Photo: The National Museum of Denmark)

In the 1950s, the now deceased Danish archaeologist Jørgen Meldgaard made a mysterious discovery in northeastern Canada:

A small, headless bear figurine, carved from a walrus tusk, was lying leaning up against the back wall of a stone fireplace in an old settlement. The bear had been positioned in a way that made it look as though it was ‘diving’ into the fireplace.

At the time, this little figurine didn’t cause much of a stir. It was just one out of a long series of discoveries that Meldgaard made during his field trips to the Igloolik region of Arctic Canada and Greenland in the 1950s and 1960s.

But when researchers at the Danish National Museum recently gained access to Meldgaard’s surviving diaries, records and photos, they realised that the discovery of the bear figurine was indeed quite sensational.

Humans and animals were close

Their examination of the material revealed that the small bear figurine could be an important key to understanding how people from more than 1,000 years ago viewed the relationship between animals and humans.

”The figurine provides us with information about some previously unknown 1,000-year-old rituals, which suggest that the Pre-Inuit, also known as the Dorset people, imagined that humans were related to certain animals in a way that’s very far from what we would imagine in today’s Western world,” says Ulla Odgaard, a senior researcher at the National Museum.

“Apparently, the Dorset people in Greenland and Canada didn’t see any antagonism between humans and animals,” she adds.

“Humans were not superior to animals; rather, it was a symbiotic co-existence. Bears and other animals functioned as mediators between mankind and the world of spirits.”

The Dorset way of thinking is also known from other early cultures

In other words, the finds reveal a belief in which animals – bears in particular – are our brothers, whose lives blend in with our own.

The walrus tusk figurine is only 3.4 cm in length and could be an important key to understanding how people more than 1,000 years ago understood the relationship between humans and bears. The figure is thought to have disappeared now, leaving today’s archaeologists with little more than Jørgen Meldgaard’s sketches and blurry photos. (Photo: The National Museum of Denmark)

The way the Dorset culture viewed the relationship between humans and animals is known as animism – a phenomenon also known from other cultures.

“We know that the relationship between bears and humans has been crucial in all pre-modern cultures. This applies almost as far back in time as we can trace – all the way back to the very earliest renderings of the world that humans have created,” says Odgaard’s colleague at the National Museum, Martin Appelt.

For instance, we see this relationship expressed in small carvings and cave paintings of humans and bears from the hunter-gatherer culture.

“Many cultures have combined human and animal features in their illustrations – e.g. a figurine of a bear with a falcon’s body, where the underside depicts a carved human head,” he says.

On many figurines from early cultures, the skeleton is cut so that it’s visible outside the body – and that’s also the case with Meldgaard’s bear figurine.

According to Appelt, this bears witness to a belief that the difference between humans and animals only lies in the skin they’re wearing, so to speak.

“So an animal is also a person – only with a different skin. And some of them have probably been regarded as spirits – i.e. people in a parallel universe to ours.”

The bear was something special

The apparent fact that bears were regarded as something special could be because the bear, along with man, is one of the few animals that were believed to transcend and travel between the worlds of land and sea.

Another explanation may be that humans and bears could change roles depending on the situation: sometimes it was the man who hunted the bear and sometimes it was vice versa.

The discovery of another bear was an eye opener

Among the thousands of unique and spectacular objects that Jørgen Meldgaard and his colleagues excavated in the Canadian settlements in the 1950s and 60s, the many fine carvings made from walrus tusks, reindeer antler and driftwood are particularly interesting to archaeologists. These include small carvings of humans, human-like creatures and various animals, but also figures which seem to contain traits from both humans and animals. The figures reveal a belief in which animals – bears in particular – are our brothers, whose lives blend in with ours. (Photo: The National Museum of Denmark)

Meldgaard also found another bear figurine in a nearby settlement.

This bear stood upright with its head sticking up and the body half buried in the gravel.

Underneath it they found a fireplace, which suggests that this bear apparently was about to rise up from the fireplace.

The combination of both of the bear figurines’ interaction with the fireplaces led the Odgaard to believe that this could be a sign of rituals.

Carved bear figurines and the symbolism of rising and diving bears is also known in other parts of the world, for instance in Siberia, where resurrection rituals have been performed for millennia, says Odgaard.

Here, the bear was the mythical ancestor that every year travels to the upper world to secure the liberation of the animals’ souls, so that humans again can hunt them.

The fireplace was the gateway to other worlds

Legends from Siberia indicate that humans could communicate with the world of spirits through the fireplace. In other words, the fireplace may have been regarded as a gateway to other worlds.

Bears are also known from Neolithic petroglyphs in Siberia and numerous finds of bear heads or headless bear figurines in the Arctic region. But none of these have been found in a ritual context like the two from Igloolik.

Bear figurines could explain lack of finds of burial sites

Since the ritual with fireplaces appears to stretch across time and space, the researchers believe the finds are of far greater importance than previously thought.

Dorset people may have dismembered their dead

Although there’s no shortage of ancient Inuit tales about the special relationship between humans and animals, the oral sources tend to dry out once we start moving toward the millennia before the Inuit settled in Arctic Canada and Greenland.

“We have so far had glaringly few archaeological finds from pre-Inuit graves on other ritual elements that could increase our understanding of how the pre-Inuit people viewed their world,” says Appelt.

“This is where the bear figurines suddenly make many pieces fall into place. Suddenly we understand the many other figures with bear heads or headless bears in a completely different way.”

That the two bear figurines from the fireplaces have their skeletons carved on the outside of their bodies also confirms a suspicion the archaeologists have had that Dorset people probably dismembered their dead and scattered them out on the fields or sunk them in the sea, so they would end up as animal food – like we’re seeing in e.g. today’s Nepal and Tibet.

“This suspicion is compounded by the fact that the few bones we’ve actually found from the Dorset culture are not whole skeletons, but simple elements – a jaw, a thighbone, etc.

This suggests that the Dorset people had a completely different view of skeletons and bodies from what we have today – which the carvings of external skeletons on the bear figurines testify to.”

Rituals transcend space and time

Appelt says that the bear figurines from Igloolik are forcing archaeologists to think outside the box.

Time and space not enough to understand the past

The archaeologist explains that when you look at archaeological finds across the world, there are so many overlaps where rituals transcend across cultures, time and space that there seems to be a connection.

“It’s very strange! And many archaeologists will surely find it unreasonable to think this way as an archaeologist – because how can things be connected in this way?” says Appelt.

”I don’t have the answer. There’s no answer book here. But I think the two headless bear figurines prove that it’s not always right to view history from within the narrow confines of time, space and traditions.

The next step for Odgaard, Appelt and their colleagues is to create an overview of Meldgaard’s records and publish the most important scientific findings.


The Danish National Museum’s comprehensive research initiative ‘Northern Worlds’ aims to generate new insights into the relationship between man and the environment over the past 15,000 years, with a perspective on the present, where substantial climatic change is taking place.

 It will also shed light on global networks by studying Northern cultures from the Ice Age hunters to the present-day populations in the cold regions.

‘Northern Worlds’ consists of more than 20 projects, headed by leading researchers from all departments at the Danish National Museum.

The bear figurines on the fireplaces are not only some of the few physical vestiges testifying to the Dorset culture’s view of life and death that archaeologist have ever come across.

The figurines may also help explain an old mystery – why archaeologists only rarely find burial sites from the earliest settlers in Greenland and Arctic Canada.

The Dorset people in Greenland and Canada (c. 700 to 1,200 AD) is an archaeological term for a non-Inuit people group from Greenland.

The Dorset culture preceded the Inuit culture in Arctic North America. Archaeologists believe the people migrated from Siberia and Alaska between 4,000 years ago and until the birth of Christ.

Iniuit legends mention Tunitt (singular Tuniq) or Sivullirmiut (‘The first inhabitants’) as a people who were displaced by the Inuit.

Archaeologists, however, doubt whether or not the Inuit met with the Dorset culture, although there is a general consensus that the two groups have lived in the same area for a period.

Dorset culture became extinct around 1902 – probably as a result of a change in climate and living conditions, but also because they were ousted by the Inuit.

“We archaeologists prefer to work from the hypothesis that we can define various periods in history and that there is a clear division between space and time. But the figurines reveal that this is not the case here,” says Appelt.

“Some phenomena, such as animism and the rituals with the fireplaces and the dismemberment of the dead, transcend time and space – which is why you simply need to view them in bits of several 100,000 years if they are to be understood and make sense.”

Humans were hunting mastodons in Mexico 250,000 years ago.  This archaeological heresy is supported by finding at Hueyatlaco.

Hueyatlaco is an archeological site in Valsequillo, Mexico. Several potential pre-Clovis localities were found in the 1960s around the edge of the Valsequillo Reservoir, Mexico.  One of these localities is the site of Hueyatlaco.  This site was excavated by Cynthia Irwin-Williams in 1962, 1964, and 1966.

One of its early excavators Virginia Steen-McIntyre writes “Hueyátlaco is a dangerous site. To even publicly mention the geological evidence for its great age is to jeopardize one’s professional career. Three of us geologists can testify to that. It’s very existence is blasphemous because it questions a basic dogma of Darwinism, the ruling philosophy (or religion, if you will) of the western scientific world for the past 150 years. That dogma states that, over a long period of time, members of the human family have generally become more and more intelligent. The Hueyátlaco site is thus ‘impossible’ because Mid-Pleistocene humans weren’t smart enough to do all that the evidence implies. Besides, there is no New World anthropoid stock from which they could have evolved.:

File:High res mastodon rendering.jpg


The Hueyatlaco Archeological Site is situated on the Tetela Peninsula, along the north shore of the Valsequillo reservoir in the State of Puebla, Mexico, approximately 100 km southeast of Mexico City and 10 km south of the City of Puebla.

In the 1960s, highly sophisticated stone tools rivaling the best work of Cro-magnon man in Europe were unearthed by Professor Juan Armenta Camacho and Dr. Cynthia Irwin-Williams at Hueyatlaco, near Valsequillo.

Dr. Cynthia Irwin-Williams

Credit: Smithsonian National Archives

After excavations in the 1960s, the site became notorious due to geochronologists’ analyses that indicated human habitation at Hueyatlaco was dated to ca. 250,000 years before the present.

Professor Juan Armenta Camacho

Professor Juan Armenta Camacho

Beds containing human artifacts at Valsequillo, Mexico, have been dated at approximately 250,000 years before the present by fission-track dating of volcanic material and uranium dating of a camel pelvis. The dilemma posed by such dates is clearly stated in the following quotation from the conclusions of the subject article.


“The evidence outlined here consistently indicates that the Hueyatlaco site is about 250,000 yr old. We who have worked on geological aspects of the Valsequillo area are painfully aware that so great an age poses an archeological dilemma. If the geological dating is correct, sophisticated stone tools were used at Valsequillo long before analogous tools are though to have been developed in Europe and Asia. Thus, our colleague, Cynthia Irwin-Williams, has criticized the dating methods we have used, and she wishes us to emphasize that an age of 250,000 yr is essentially impossible.”
(Steen-McIntyre, Virginia, et al; “Geologic Evidence for Age of Deposits at Hueyatlaco Archeological Site, Valsequillo, Mexico,” Quaternary Research, 16:1, 1981.)


These controversial findings are orders of magnitude older than the scientific consensus for habitation of the New World (which generally traces widespread human migration to the New World to 13,000 to 16,000 ybp). The findings at Hueyatlaco have mostly been repudiated by the larger scientific community, and have seen only occasional discussion in the literature

According to  Steen-McIntyre “we have evidence for two primitive human skulls. The Dorenberg skull was collected in the area over 100 years ago (Reichelt,1899 (1900)) . The interior cavities were filled with a diatomite that contains the same Sangamon-age suite of taxa that occurs associated with the artifacts at Hueyátlaco (VanLandingham 2000, 2002b,c, 2003). It was on display in a museum in Leipzig for many years, and was destroyed during the bombings of WW II. We are looking for a photo or drawing of it.

The second skull, the Ostrander skull, is rumored to have been collected illegally at Hueyátlaco sometime in the late 60’s or early 70’s and recently to have been turned over to a Native American tribe for reburial. No attempt was made to date it.”

Ostrander skull to the right, allegedly from the Hueyatlaco Site. On the left a modern skull

Credit:  Austin Whittall

Cynthia Irwin-Williams led the team that first excavated the site in 1962 The dig is often associated with Virginia Steen-McIntyre because of her continuing efforts to publicize her findings and opinions. However, the site was actually discovered by Juan Armenta Camacho and Irwin-Williams. Steen-McIntyre joined the team in 1966 as a graduate student, at the request of project geologist Hal Malde. The excavation was associated with the U.S. Geological Survey.

The region, about 75 miles SE of Mexico City, was known for its abundance of animal fossils, and Irwin-Williams described Hueyatlaco as a “kill site” where animals were hunted and butchered.

These tools are believed to be 250,000 years old from the Hueyatlaco site.

Credit: Dr. Cynthia Irwin-Williams/H.S. Rice

Excavations were conducted via standard protocols, including securing the sites to prevent trespass or accidental disturbances. During excavation, investigators discovered numerous stone tools. The tools ranged from relatively primitive implements at a smaller associated site, to more sophisticated items such as scrapers and double-edged blades uncovered at the main excavation site. The diversity of tools made from non-local materials suggested that the region had been used by multiple groups over a considerable period.

Credit: Chris Hardaker

In 1967, Jose L. Lorenzo of the Instituto Nacional de Antropología e Historia claimed that implements had been planted at the site by local laborers in such a way as to make it difficult or impossible to determine which artifacts were discovered in situ and which were planted. Irwin-Williams counter-argued that Lorenzo’s claims were malicious and without merit. Furthermore, in 1969 Irwin-Williams cited statements of support from three prominent archeologists and anthropologists (Richard MacNeish, Hannah Marie Wormington and Frederick A. Peterson) who had each visited the site independently and attested to the integrity of the excavations and the professionalism of the group’s methodology

Credit: Chris Hardaker

In mid-1969, Szabo, Malde and Irwin-Williams published their first paper about dating the excavation site. The stone tools were discovered in situ in a stratum that also contained animal remains. Radiocarbon dating of the animal remains produced an age of over 35,000 ybp. Uranium dating produced an age of 260,000 ybp, ± 60,000 years.

The site had been buried by the ash of La Malinche. The reservoir, which lies 100 km southeast of Mexico City and south of the city of Puebla is surrounded by four of Mexico’s famous volcanoes: Tláloc, Iztaccíhuatl, Popocatepetl, and La Malinche, which is shown below.


Credit: Wikipedia

The authors admitted that they had no definitive explanation for the anomalous results. However, Malde suggested the tool-bearing strata had possibly been eroded by an ancient streambed, thus combining older and newer strata and complicating dating.

Credit: Chris Hardaker

In 1973, Steen-MacIntyre, Malde and Roald Fryxell returned to Hueyatalco to re-examine the geographic strata and more accurately determine an age for the tool-bearing strata. They were able to rule out Malde’s streambed hypothesis. Moreover, the team undertook an exhaustive analysis of volcanic ash and pumice from the original excavation site and the surrounding region. Using the zircon fission-track dating method, geochemist C.W. Naeser dated samples of ash from Hueyatlaco’s tool-bearing strata to 370,000 ybp +/- 240,000 years.

The confirmation of an anomalously distant age for human habitation at the Hueyatlaco site led to tension between Irwin-Williams and the other team members. Malde and Fryxell announced the findings at a Geological Society of America meeting, admitting that they could not account for the anomalous results. Irwin-Williams responded by describing their announcement as “irresponsible”.  Given the substantial margin of error for the fission-track findings, and the then-new method of uranium dating, Irwin-Williams asserted that Hueyatlaco had not been accurately dated to her satisfaction.

Credit: Chris Hardaker

Excerpt of letter to Marie Wormington from Dr. Cynthia Irwin-Williams [circa 1969]:

“…Meanwhile, I recently got a letter from Hal, with some (completely wild) uranium dates on Valsequillo material. I don’t see how he can take them seriously since they conflict with the archaeology, with his own geologic correlations, and with a couple C14 dates. However, God help us, he wants to publish right away! I am enclosing a copy of Hal’s letter and my reply. Needless to say any restraint you can exercise on him would be greatly appreciated. All we need to do at this point is to put that stuff in print and every reputable prehistorian in the country will be rolling in the aisles.”

On March 30, 1981, Steen-McIntyre wrote to Estella Leopold, the associate editor of Quaternary Research: “The problem as I see it is much bigger than Hueyatlaco. It concerns the manipulation of scientific thought through the suppression of ‘Enigmatic Data,’ data that challenges the prevailing mode of thinking. Hueyatlaco certainly does that! Not being an anthropologist, I didn’t realize the full significance of our dates back in 1973, nor how deeply woven into our thought the current theory of human evolution had become. Our work at Hueyatlaco has been rejected by most archaeologists because it contradicts that theory, period.”

Eventually, Quaternary Research (1981) published an article by Virginia Steen-McIntyre, Roald Fryxell, and Harold E. Malde. It upheld an age of 250,000 years for the Hueyatlaco site. Cynthia Irwin-Williams (1981) objected to these findings in a letter responding to these authors. Her objections were answered point-for-point in a counter letter from Malde and Steen-McIntyre (1981).

Credit: Chris Hardaker

The case of Virginia Steen-McIntyre opens a rare window into the actual social processes of data suppression in paleoanthropology, processes that involve a great deal of hurt and conflict. In general, however, this goes on behind the scenes, and the public sees only the end result—the carefully edited journals and books that have passed the censors.

The Sangamonian Stage, also known as the Sangamon interglacial, is the name used by Quaternary geologists to designate the last interglacial period in North America from 125,000—75,000 years ago, a period of 0.05 million years. The Sangamonian Stage precedes the Wisconsinan (Wisconsin) Stage and follows the Illinoian Stage in North America

In recent times the Hueyatlaco Site has been reinvestigated by Dr. Sam VanLandingham using diatom dating methodology to confirm the anomalously old dates assigned by Malde, Steen-McIntyre and Fryxell:
Important artifacts have been found in situ (i.e., not redeposited) within lacustrine deposits in the Valsequillo region. These deposits contain many diatoms which indicate an age corresponding to the Sangamonian Interglacial sensu lato (80,000 to ca. 220,000yr BP). Two of the four samples in this study are associated with the Dorenberg skull or with stratigraphic units which contain bifacial tools. The remaining two samples are from diatomaceous deposits which are also Sangamonian and stratigraphically above the artifact units. These four diatomaceous samples yielded 30 extinct and 143 extant diatom taxa.

The ages of the four samples correspond to other diatomaceous samples (some of which are associated with artifacts) from nearby Valsequillo localities. A post-Sangamonian age for these four diatom-bearing samples is discounted by the presence of Navicula bronislaae and N. dorenbergi, both of which have short stratigraphic ranges and are known only from the Sangamonian (or its equivalents), and by 13 diatoms which evidently have known long stratigraphic ranges and extinctions before the end of the Sangamonian.

An age no older than Sangamonian for the artifacts and their enclosing diatomaceous deposits is indicated by the presence of two diatoms (Epithemia zebra var. undulata and Navicula creguti) known only from Sangamonian (or = age) or younger and by an extant diatom, Cymbella cistula var. gibbosa (C. gibbosa), which has its first occurrence in the Sangamonian.
The diatom biostratigraphy presented herein establishes a minimum (Sangamonian) and a maximum (Illinoian) age for the younger (bifacial) artifacts at the Hueyatlacoarchaeological site in units B,C, and E, Puebla, Mexico.

VanLandingham  used  diatom biostratigraphy in determining a minimum (Sangamonian = 80,000–ca.220,000 yr. BP) and a maximum (Illinoian = 220,000–430,00 yr. BP) age for the Hueyatlaco artifacts, Puebla, Mexico. Nova Hedwigia (February, 2009), Beiheft 135, p. 15-36.

Quoting the Abstract: The diatom biostratigraphy presented herein establishes a minimum (Sangamonian) and a maximum (Illinoian) age for the younger (bifacial) artifacts at the Hueyatlaco archaeological site in units B,C, and E, Puebla, Mexico. One of the 13 samples in this study is from a position of Sangamonian age which is stratigraphically higher than the artifacts. The minimum age of this sample (from unit B) is demonstrated by 6 taxa which became extinct at the end of the Sangamonian , and its maximum age (also Sangamonian) is denoted by 3 taxa with earliest known first occurrences in the Sangamonian. The diatoms of the remaining 12 samples have a minimum age of Sangamonian. Three of the 13 samples are in unit I and no Hueyatlaco artifacts are known below this unit.


^ Irwin-Williams, C., et al., Comments on the Associations of Archaeological Materials and Extinct Fauna in the Valsequillo Region Puebla Mexico, American Antiquity, Volume 34, Number 1, Pages 82-83, Jan 1969

^ Szabo, B.J., Malde, H.E., and Irwin-Williams, C., Dilemma Posed By Uranium-Series Dates On Archaeologically Significant Bones From Valsequillo Puebla Mexico, Earth and Planetary Science Letters, Volume 6, Pages 237-244, Jul 1969

^ Gonzalez, Silvia; Huddart, David; and Bennett Matthew. (2006) Valsequillo Pleistocene archaeology and dating : ongoing controversy in Central Mexico . World Archaeology, 2006, vol. 38, no4, pp. 611-627.

a b Irwin-Williams, C., et al., Comments on the Associations of Archaeological Materials and Extinct Fauna in the Valsequillo Region Puebla Mexico, American Antiquity, Volume 34, Number 1, Pages 82-83, Jan 1969

^ Irwin-Williams, Cynthia. (1978) Summary of Archeological Evidence from the Valsequillo Region, Puebla, Mexico. In Cultural Continuity in Mesoamerica, David L. Browman, ed. The Hague: Mouton Publishers.

a b c d e f g h Webb, Mark Owen and Suzanne Clark. (1999). “Anatomy of an Anomaly .” Disputatio, 6.

^ Szabo, B.J., Malde, H.E., and Irwin-Williams, C., Dilemma Posed By Uranium-Series Dates On Archaeologically Significant Bones From Valsequillo Puebla Mexico, Earth and Planetary Science Letters, Volume 6, Pages 237-244, Jul 1969

^ Steen-McIntyre, V., R. Fyxell and H. Malde. (1981) Geologic Evidence for Age Deposits at Hueyatlaco Archaeological Site Valsequillo Mexico, Quaternary Research, Number 16, Pages 1-17, 1981


^ VanLandingham, S.L., Corroboration of Sangamonian Age of Artifacts From the Valsequillo Region Puebla Mexico By Means of Diatom Biostratigraphy, Micropaleontology, Volume 50, Number 4, Pages 313-342, 2004

^ VanLandingham, S.L., Diatom Evidence For Autocthonous Artifact Deposition In the Valsequillo Region Puebla Mexico During Sangamonian (sensu lato = 80,0000 to ca. 220,000 yr BP and Illinoian (220,000 to 430,000 yr BP)), Journal of Paleolimnology, Volume 36, Number 1, Pages 101-116, Jul 2006