archaeological city
Collapse of Aztec society linked to catastrophic salmonella outbreak
DNA of 500-year-old bacteria is first direct evidence of an epidemic — one of humanity's deadliest — that occurred after Spanish conquest.

One of the worst epidemics in human history, a sixteenth-century pestilence that devastated Mexico’s native population, may have been caused by a deadly form of salmonella from Europe, a pair of studies suggest.

In one study, researchers say they have recovered DNA of the stomach bacterium from burials in Mexico linked to a 1540s epidemic that killed up to 80% of the country’s native inhabitants. The team reports its findings in a preprint posted on the bioRxiv server on 8 February1.

This is potentially the first genetic evidence of the pathogen that caused the massive decline in native populations after European colonization, says Hannes Schroeder, an ancient-DNA researcher at the Natural History Museum of Denmark in Copenhagen who was not involved in the work. “It’s a super-cool study.”

Dead bodies and ditches

In 1519, when forces led by Spanish conquistador Hernando Cortés arrived in Mexico, the native population was estimated at about 25 million. A century later, after a Spanish victory and a series of epidemics, numbers had plunged to around 1 million.

The largest of these disease outbreaks were known as cocoliztli (from the word for ‘pestilence’ in Nahuatl, the Aztec language). Two major cocoliztli, beginning in 1545 and 1576, killed an estimated 7 million to 18 million people living in Mexico’s highland regions.

“In the cities and large towns, big ditches were dug, and from morning to sunset the priests did nothing else but carry the dead bodies and throw them into the ditches,” noted a Franciscan historian who witnessed the 1576 outbreak.

There has been little consensus on the cause of cocoliztli — although measles, smallpox and typhus have all been mooted. In 2002, researchers at the National Autonomous University of Mexico (UNAM) in Mexico City proposed that a viral haemorrhagic fever, exacerbated by a catastrophic drought, was behind the carnage2. They compared the magnitude of the 1545 outbreak to that of the Black Death in fourteenth-century Europe.

Bacterial genomics

In an attempt to settle the question, a team led by evolutionary geneticist Johannes Krause at the Max Planck Institute for the Science of Human History in Jena, Germany, extracted and sequenced DNA from the teeth of 29 people buried in the Oaxacan highlands of southern Mexico. All but five were linked to a cocoliztli that researchers think ran from 1545 to 1550.

Ancient bacterial DNA recovered from several of the people matched that of Salmonella, based on comparisons with a database of more than 2,700 modern bacterial genomes.

Further sequencing of short, damaged DNA fragments from the remains allowed the team to reconstruct two genomes of a Salmonella enterica strain known as Paratyphi C. Today, this bacterium causes enteric fever, a typhus-like illness, that occurs mostly in developing countries. If left untreated, it kills 10–15% of infected people.

It’s perfectly reasonable that the bacterium could have caused this epidemic, says Schroeder. “They make a really good case.” But María Ávila-Arcos, an evolutionary geneticist at UNAM, isn’t convinced. She notes that some people suggest that a virus caused the cocoliztli, and that wouldn’t have been picked up by the team’s method.

The question of origin

Krause and his colleagues’ proposal is helped by another study posted on bioRxiv last week, which raises the possibility that Salmonella Paratyphi C arrived in Mexico from Europe3.

A team led by Mark Achtman, a microbiologist at the University of Warwick in Coventry, UK, collected and sequenced the genome of the bacterial strain from the remains of a young woman buried around 1200 in a cemetery in Trondheim, Norway. It is the earliest evidence for the now-rare Salmonella strain, and proof that it was circulating in Europe, according to the study. (Both teams declined to comment on their research because their papers have been submitted to a peer-reviewed journal.)

“Really, what we’d like to do is look at both strains together,” says Hendrik Poinar, an evolutionary biologist at McMaster University in Hamilton, Canada. And if more ancient genomes can be collected from Europe and the Americas, it should be possible to find out more conclusively whether deadly pathogens such as Salmonella arrived in the New World from Europe.

The existence of Salmonella Paratyphi C in Norway 300 years before it appeared in Mexico doesn’t prove that Europeans spread enteric fever to native Mexicans, says Schroeder, but that hypothesis is reasonable. A small percentage of people infected with Salmonella Paratyphi C carry the bacterium without falling ill, so apparently healthy Spaniards could have infected Mexicans who lacked natural resistance.

Paratyphi C is transmitted through faecal material, and a collapse of social order during the Spanish conquest might have led to the poor sanitary conditions that are ripe for Salmonella spread, Krause and his team note in the paper.

Krause’s study offers a blueprint for identifying the pathogens behind ancient outbreaks, says Schroeder. His own team plans to look for ancient pathogens in Caribbean burial sites that seem to be linked to catastrophic outbreaks, and that were established after the Europeans arrived. “The idea that some of them might have been caused by Salmonella is now a distinct possibility,” he says.

Forgotten Mayan city 'discovered' in Central America by 15-year-old

A 15-year-old boy believes he has discovered a forgotten Mayan city using satellite photos and Mayan astronomy.

William Gadoury, from Quebec, came up with the theory that the Maya civilization chose the location of its towns and cities according to its star constellations.

He found Mayan cities lined up exactly with stars in the civilization’s major constellations.

Studying the star map further, he discovered one city was missing from a constellation of three stars.

Using satellite images provided by the Canadian Space Agency and then mapped on to Google Earth, he discovered the city where the third star of the constellation suggested it would be. Read more.


Lt. Colonel Percy Harrison Fawcett was a British officer and archaeologist who mysteriously disappeared in 1925 during an expedition to uncover an ancient lost city in the jungle of Brazil. Fawcett first encountered the city, which he referred to as the Lost City of Z, in a cryptic document known as Manuscript 512 which described an enigmatic Grecian city hidden deep in the heart of the Amazonian jungle. On May 29th, 1925, Fawcett, with his son Jack and their companion Raleigh Rimell, departed into the jungle and were never seen again. 

The fate of Fawcett and his party remains unknown. Some believe that they were killed by indigenous people such as the Kalapalo, who were the last people to see them alive. Others believe that they died of natural causes, as many members of the party were ill the last time they were seen. Still others speculate that Fawcett and his party were held captive and lived out the rest of their lives with the Kalapalo people.

Considered one of the world’s greatest explorers at the time, Fawcett’s life and journeys inspired Sir Arthur Conan Doyle to write his 1912 novel The Lost World. Since his disappearance in 1925, over 100 would-be rescuers and explorers have disappeared in the Amazon in an attempt to discover the truth about really happened to Fawcett and his expedition. 

Why Palmyra was such a spectacular and unique archaeological site

The ancient city of Palmyra in the Syrian desert has seen renewed fighting in recent days after the so-called Islamic State recaptured it on 11 December.

Before Palmyra was ravaged by the war, it stood as one of the most important cultural centre of the ancient world. Its monuments displayed impressive artistic and architectural features associated with several different civilisations. It remains on the UNESCO World heritage list.

“Palmyra was worth being on the UNESCO list because it was one of the best preserved classical sites anywhere, it had a lot of unique architecture, and combined many different cultural elements, including from the near-East, Europe and elsewhere”, Mark Altaweel, reader in Near East Archaeology at UCL, told IBTimes UK. Read more.
Teotihuacan, Mexico’s Pyramid City, Worshipped Water, Scholar Says
A Mexican archaeologist says the ancient city of Teotihuacan, which includes some of the world’s biggest pyramids, worshipped water.
By Juan Montes

The key to understanding one of this country’s most mysterious sites may be all in the water.

The ancient city of Teotihuacan, which includes some of the world’s biggest pyramids, collapsed 1,400 years ago. Ever since then, the site in central Mexico has confounded scholars.

Verónica Ortega, of Mexico’s National Institute of Anthropology and History, says her excavations in recent months at Teotihuacan’s square of the Pyramid of the Moon have yielded a breakthrough, suggesting the whole city was an aquatic sanctuary consecrated to the worship of water. The 43-year-old archaeologist has found canals and cavities similar to pools beneath the square, along with sculptures of water gods. Excavations at Teotihuacan’s other two pyramids uncovered seashells, water pitchers and more aquatic elements.

“Water is the true protagonist of Teotihuacan. If there was a city in the ancient world where water was worshipped, it was Teotihuacan,” Ms. Ortega said on a recent morning in her office at the excavation site, which looks out on one of Teotihuacan’s three pyramids.

Her theory challenges the notion that the people of the area worshipped various deities of equal importance, such as the god of fire, the god of time and several gods of water. Other Mexican archaeologists have expressed admiration as well as scientific skepticism about Ms. Ortega’s idea.

“This is an innovative, interesting proposal, but she has to demonstrate it properly,” said Leonardo López Lújan, a local archaeologist. “To this day, I still think water was not the main ingredient present here, but also the gods of fire and time.”

Teotihuacan is also home to the mural of Tlalocan, which has pyramid-like images.

Teotihuacan is in a semiarid plateau surrounded by mountains 30 miles northeast ofMexico City. The city peaked from 200 to 450 AD, housing as many as 150,000 people before its demise around 600 AD. Its zenith coincided with the decline of the Roman Empire in Europe.

Its pyramids are rivaled only by those at Mayan sites in Central America. But unlike themuch-studied Mayans, little is known about the people of Teotihuacan, mainly because they had no complex form of writing. Thus far, no carved slabs with writing have been found in the area, nor any royal tombs.

The Aztecs, a warrior people who came from the north and settled in central Mexico 700 years after the city’s collapse, named the area Teotihuacan, which means “the place where men become gods.” The two biggest pyramids bear the names of the sun and the moon; the Aztecs linked both structures with their myth of creation.

But Ms. Ortega’s excavations suggest the Aztecs got it wrong—and that the worship of water, in various forms such as lakes, heavy rains or flooding—played a crucial role. “The Pyramid of the Moon was actually consecrated to the goddess of rivers and lakes, Chalchuihtlicue in Aztec, while the god of storms, Tlaloc, was worshipped in the so-called Pyramid of the Sun,” Ms. Ortega said.

She partially bases her theory of Teotihuacan’s worship of water on a sumptuous mural of Tlalocan, which is found at a palace in the city. In vivid red and blue, it depicts a kind of pyramid from which streams of water are flowing. Ms. Ortega also found four canals coming out from a temple at the square of the moon.

For the Teotihuacan people, who were mostly farmers, water was everything. Some years, the city suffered as many as eight dry months. “Only the aquatic gods guaranteed the renewal of the life cycle,” Ms. Ortega said. When the rainy season arrived, the city collected water in canals and wells.

“We can’t rule out anything,” said Linda Manzanilla, one of Mexico’s foremost experts in Teotihuacan. “Water was the most important factor in the half-desert region where Teotihuacan sits.”

Ms. Ortega, who plans to detail her theory in a scholarly paper, agrees that Teotihuacan had other deities besides water, such as gods of fire, but they played a lesser role. In Teotihuacan, she said, fire was closely linked to water as both elements came from thunderstorms.

Most scholars agree the people of Teotihuacan built the pyramids to emulate the surrounding mountains, where they believed the gods dwelt. By building the pyramids, the teotihuacanos tried to bring the gods to their city.

Budget cuts ordered this year by the Mexican government as oil prices tumbled pose a hurdle for Ms. Ortega and her colleagues. Ms. Ortega’s 2016 project budget was cut by 50% to $22,000. She needs three times that amount to continue the research properly, she said, adding that only a fraction of the site has been properly excavated.

“The present is king, even for archaeologists,” Ms. Ortega said with a chuckle. “Maybe we’ll have to wait a bit longer for Teotihuacan to reveal some of its deepest secrets.”


Se complen 10 años del descubrimiento del monolito de la diosa Tlaltecuhtli

Es la escultura mexica más grande encontrada hasta ahora.

Hace una década, el 2 de octubre se convirtió de nuevo en una fecha para recordar, pero por una causa afortunada. De los restos del antiguo centro ceremonial de México-Tenochtitlan volvía a surgir una diosa; en 1978 despertó Coyolxauhqui, 28 años después resurgiría Tlaltecuhtli, una deidad que “a todo color” y en su iconografía, hace referencia al ciclo vida-muerte, a la tierra como devoradora de cadáveres.

Tras más de 500 años sepultada, un equipo de especialistas del Programa de Arqueología Urbana del Instituto Nacional de Antropología e Historia (INAH) descubrió la colosal escultura mexica de 4.17 x 3.62 metros, aproximadamente 40 centímetros de espesor y cerca de 12 toneladas, en la intersección de las calles República de Argentina y Guatemala, en el Centro Histórico de la Ciudad de México.

En los años subsecuentes, el Proyecto Templo Mayor, liderado por el arqueólogo Leonardo López Luján, ha registrado múltiples descubrimientos asociados a la representación de la deidad tenochca: 45 ofrendas en las que estaban distribuidos alrededor de 70 mil objetos, por ejemplo, en la número 141 se contabilizó un aproximado de 16 mil, en los que conchas y caracoles son el grueso. En oblaciones como ésta también abundaban los restos de lobos, pumas y linces.

Una década con Tlaltecuhtli no podía pasar desapercibida para el Museo del Templo Mayor (MTM), donde el monolito ocupa un lugar central, aunque cabe mencionar que existen más de 40 representaciones de esta deidad expuestas en su mayoría en dicho recinto y en el Museo Nacional de Antropología. Es por ello que el MTM invita a recordar el descubrimiento de la escultura mexica más grande encontrada hasta ahora, en el lugar mismo donde se suscitó.

El punto de encuentro para este recorrido, en el que además se abordarán otros hallazgos recientes en el Recinto Ceremonial de Tenochtitlan, como fue la ubicación de los vestigios de la escuela para nobles o Calmécac, será el vestíbulo del Museo del Templo Mayor, todos los sábados de octubre, a las 12:00 horas. La actividad es gratuita (presentando el boleto de acceso al museo).

Asimismo, en el sótano del edificio (ubicado en Guatemala 22) se realiza una recreación de las estructuras prehispánicas colindantes, utilizando imágenes fotográficas, audio y video. Para mayores informes sobre este recorrido comunicarse al teléfono 4040 5600, ext. 412934.

Para los mayores de 12 años, el MTM impartirá este domingo 2 de octubre un taller en punto de las 10:30 horas, para que se lleven a casa una impresión de Tlaltecuhtli, aplicando la técnica del stencil. La actividad no tiene costo, sólo se sugiere llevar ropa que pueda mancharse.

Otro taller está pensado para que toda la familia descubra los elementos más destacados del faldellín de la diosa mexica, para producir un brazalete con la técnica del repujado. Esto será los sábados 8 y 15 de octubre, a las 11:00 horas, también de manera gratuita.

El mito detrás de Tlaltecuhtli

Tlaltecuhtli era un monstruo con articulaciones llenas de ojos y bocas con las cuales mordía como bestia salvaje. Para aplacarla y crear la vida, dos de los hijos de la pareja creadora: los dioses Quetzalcóatl (Serpiente emplumada) y Tezcatlipoca (Espejo humeante), se transformaron a sí mismos en dos grandes serpientes, explica la doctora Diana Magaloni Kerpel, ex directora del Museo Nacional de Antropología del INAH.

En su ensayo El origen mítico de las ciudades: la iconografía de la creación, Magaloni narra que ambos desgarraron al gran lagarto Tlaltecuhtli por la mitad. “Una parte sirvió para formar el firmamento, la otra para hacer la tierra. Posteriormente los dioses hicieron con las partes de su cuerpo todas las cosas de vida: su pelo se convirtió en árboles, flores y hierbas; su piel, en los prados; sus incontables ojos, en pozos de agua; sus bocas, en grandes ríos y profundas cuevas; y sus narices en montañas”.

El mito —continúa la historiadora del arte— describe que a la diosa de la tierra se le oía llorar en las noches porque sufría enormemente, rogando ser alimentada con corazones y sangre humanos, la única medicina que aliviaba su dolor. Fue así como el desmembramiento de Tlaltecuhtli produjo “no sólo un orden en el universo, separando la tierra del cielo, sino que el precio de tal ruptura fue que Tlaltecuhtli, como la primera víctima de la creación, exigió que otras víctimas la alimentaran.

“Tlaltecuhtli a través de su muerte y resurrección, se convierte así en el símbolo de la renovación constante mediante el sacrificio”. Es por ello que este mito enarbola varios conceptos fundamentales de las ciudades mesoamericanas, refiere en su texto, de manera que “la diosa de la tierra que sostiene la creación a través de su propio sacrificio, explica el devenir del cosmos y del tiempo ya que es el principio que promueve las múltiples creaciones del mundo”.