The Incas used cutting-edge technology to power their empire

In the 15th and early 16th Centuries, a small island in Lake Titicaca was one of South America’s most important religious sites. Revered as the birthplace of the Sun, the Moon and the Inca dynasty, Isla del Sol (“Island of the Sun”) drew pilgrims from across the Andes.

A few years ago, I followed in their footsteps, catching a boat from the Bolivian town of Copacabana across the choppy, gunboat-grey lake, which sits at an altitude of 3,812m, making it the only place on the planet a traveller can “suffer from sea-sickness and mountain-sickness at the same time”, according to the British explorer Percy Harrison Fawcett, who visited in the early 1900s.

After docking on Isla del Sol’s north-east coast, I followed a centuries-old trail past a host of Inca and pre-Inca ruins – tambos (waystations), shrines, temples, plazas, altars and a ceremonial complex that includes Titikala, a slab of sandstone from which Andean creator god Viracocha is said to have brought forth the Sun and the Moon.

These deceptively simple feats of agricultural engineering helped the Inca to build the largest empire in South American history

Captivated by the ancient sites and the views of the snow-streaked Cordillera Real in the distance, I paid little attention to the terraced fields snaking along the hillsides of the island. Yet these deceptively simple feats of agricultural engineering helped the Inca to build the largest empire in South American history.

Known as Andenes (Spanish for “platforms”), these terraced fields are scattered across the central Andes. First constructed around 4,500 years ago by ancient cultures across the region, they were perfected by the Inca, who emerged in the 12th Century and were masters of adopting and adapting techniques, strategies and belief systems from other societies. Andenes, says Cecilia Pardo Grau, curator of the British Museum’s current Peru: a journey in time exhibition, was “a creative way of defying the terrain… that allows for an efficient way of growing [crops]”.

They allowed Andean communities to overcome challenging environments, including steep slopes, thin soils, extreme and sharply fluctuating temperatures, and scant or seasonal rainfall. Fed by artificial pools and elaborate irrigation systems, Andenes significantly expanded the area of cultivable land. They also conserved water, reduced soil erosion and – thanks to stone walls that absorbed heat during the day and then released it at night – protected plants from severe frosts.

This enabled farmers to grow dozens of different crops, from maize and potatoes to quinoa and coca, many of which would not otherwise have survived in the region. The upshot was a dramatic increase in the overall amount of food produced.

Beyond their ingenuity, Andenes also have an artistic quality, forming vast geometric patterns on the landscapes of the Andes. Some look like giant green staircases carved into the mountainside, while others are made up of sets of concentric circles, capturing the attention like an optical illusion.

One of the most impressive is the Peruvian archaeological site of Moray, which resembles a natural amphitheatre. Located around 50km north of the former Inca capital of Cuzco and 3,500m above sea level, it demonstrates how andenes were used to create a range of microclimates. Thanks to the varying designs, sizes, depths and orientations of the terraces, the temperature differential between the highest and lowest are around 15C. Moray has been described as an “agricultural research station”: soil samples from across the empire have been discovered here and researchers argue the Inca may have used the site to experiment with practices like crop rotation, domestication and hybridisation.

Sophisticated agricultural techniques such as Andenes played a vital role in the expansion of the Inca empire, which was known as Tawantinsuyu and spanned much of modern-day Peru, western Bolivia, southwest Ecuador, south-west Colombia, north-west Argentina and northern Chile at its height. One of the oldest surviving accounts of their use comes from Garcilaso de la Vega (1539-1616), the son of an Inca noblewoman and a Spanish conquistador. After capturing new territory, the Inca started to expand the amount of agricultural land by bringing in skilled engineers, de la Vega noted in his book, Royal Commentaries of the Incas.

“Having dug the [irrigation] channels, they levelled the fields and squared them so that the irrigation water could be adequately distributed,” he wrote. “They built terraces on the mountains and hillsides, wherever the soil was good… In this way the whole hill was gradually brought under cultivation, the platforms being flattened out like stairs in a staircase and all the cultivable and irrigable land being put to use.”

The newly expanded land was subsequently split into three parts: one for the Inca emperor; one for religious purposes; and one for the community, tranches of which were then distributed by local leaders. Although they were not taxed, farmers were required to spend time working on the emperor’s and the religious lands, as well as their own.

Techniques such as andenes were combined with policies such as mitma, where people were moved to recently conquered territories to help cement Inca control; and mit’a, a form of compulsory public service used to provide manpower to build infrastructure, including a road network tens of thousands of kilometres long.

This approach to agricultural, community and imperial organisation allowed the Inca to amass large surpluses of food for use during droughts, floods, conflicts and other lean periods. These stockpiles – which included chuño, freeze-dried potatoes produced by repeated exposure to frost and bright sunshine – were kept in huge storehouses called qullqas. In the absence of a written language, the Inca used a complex system of multicoloured knotted strings known as quipu (or khipu) to maintain inventories, as well as keep track of population and astronomical data. Some academics believe quipu may even have been used to record narratives such as stories, songs and poems.

Grau argues that quipu – examples of which are on display in the British Museum’s exhibition – were central to Inca society. “They inherited this knowledge from the Wari, a society that existed in the southern highlands, 400 years before the Inca,” she said. “The Inca used a decimal system: they had a different knot for every number from one to nine, and then for tens, hundreds and thousands… the quipu was key in the way the empire functioned and was organised.”

Ultimately, the andenes, stockpiles and quipus helped the Inca to steadily expand an empire that eventually dominated a great swath of South America, encompassed 12 million people and produced majestic citadels such as Machu Picchu.

But the arrival of the Spanish conquistadors in the 16th Century triggered the overthrow of the Inca and the decline of the Andenes. Colonial violence, epidemics of European diseases and forced displacement devastated the indigenous populations of the central Andes. European crops and agriculture practices were introduced and quickly spread throughout the region.

READ ASLO: TWO INCA MEASUREMENT SYSTEMS CALCULATED BY POLISH ARCHITECT

Yet while many andenes were abandoned or fell into disrepair, they never disappeared completely. Drawing on knowledge passed down over the generations, many Andean farmers continue to use them today, and though often overlooked by travellers, they remain a common sight in places such as Isla del Sol and the wider Titicaca region, the Sacred Valley near Machu Picchu, and the Colca Canyon in southern Peru, a fissure twice the depth of the Grand Canyon.

In recent years, there has also been renewed academic interest in Andenes as a form of sustainable agriculture that could help the world cope with the climate crisis, water scarcity and soil erosion. The Food and Agriculture Organization of the UN, for example, describes traditional Andean culture as “one of the best examples of the adaptation and knowledge of farmers to their environment”, and highlights its sustainable approach to land usage, water management, soil protection and crop biodiversity.

Four and a half thousand years after they first emerged, the terraced fields of the Andes appear to be ahead of their time.

Archaeologists Discover 1,200-Year-Old Mummy Tied With Rope

Archaeologists excavating an underground tomb in Peru have uncovered a strange mummy preserved fully bound up in ropes, with its hands covering its face. The remains of the individual, whose sex has not been identified, was found at the Cajamarquilla archaeological site, some 16 miles from the capital city of Lima.

According to the team, the mummy dates back 1,200-800 years and belonged to the pre-Inca civilisation that developed between the Peruvian coast and mountains.

The excavation at Cajamarquilla is being led by archaeologist Pieter Van Dalen Luna of the California State University-San Marcos.

‘The main characteristic of the mummy is that the whole body was tied up by ropes and with the hands covering the face,’ Professor Van Dalen Luna said.

This elaborate binding, he explained, ‘would be part of the local funeral pattern.’

The mummified individual, Professor Van Dalen Luna explained, would have lived in the high Andean region of what is today Peru — some 600–200 years before the rise of the Inca people. 

‘Radiocarbon dating will give a more precise chronology,’ he added.

The underground tomb in which the mummy was found also harboured other funerary offerings. Among these discoveries were stone tools and ceramic pots within which were traces of vegetable matter, the archaeologists said.

The team added that the nature of the burial indicated that the region would have been multi-ethnic in the late pre-Hispanic period. Peru is home to hundreds of archaeological sites derived from cultures that developed both before and after the Inca Empire.

The Inca once dominated the southern part of South America, all the way from southern Ecuador and Colombia to central Chile, and first arose in the Peruvian highlands sometime in the early 13th Century.

The Incan Empire fell at the hands of the Spanish conquistadors, who began their invasion in 1532 and seized the Inca’s last stronghold in 1532.

WHY DID ANCIENT SOUTH AMERICAN CULTURES SACRIFICE THEIR CHILDREN?

Child sacrifice seems to have been a relatively common occurrence in the cultures of ancient Peru, including the pre-Incan Sican, or Lambayeque culture and the Chimu people who followed them, as well as the Inca themselves.

Among the finds revealing this ritual behaviour are the mummified remains of a child’s body, discovered in 1985 by a group of mountaineers.

The remains were uncovered at around 17,388ft (5,300 metres) on the southwestern ridge of Cerro Aconcagua mountain in the Argentinean province of Mendoza. The boy is thought to have been a victim of an Inca ritual called capacocha, where children of great beauty and health were sacrificed by drugging them and taking them into the mountains to freeze to death.

Ruins of a sanctuary used by the Inca to sacrifice children to their gods was discovered by archaeologists at a coastal ruin complex in Peru in 2016. Experts digging at Chotuna-Chornancap, in North Lima, discovered 17 graves dating to at least the 15th century. This included the graves of six children placed side by side in pairs of shallow graves. 

Capacocha was a ritual that most often took place upon the death of an Inca king. The local lords were required to select unblemished children representing the ideal of human perfection.

Children were married and presented with sets of miniature human and llama figurines in gold, silver, copper and shell. The male figures have elongated earlobes and a braided headband and the female figurines wore their hair in plaits.

The children were then returned to their original communities, where they were honoured before being sacrificed to the mountain gods on the Llullaillaco Volcano. 

The phrase Capacocha has been translated to mean ‘solemn sacrifice’ or ‘royal obligation.’

The rationale for this type of sacrificial rite has typically been understood as commemorating important life events of the Incan emperor, to send them to be with the deities upon their death, to stop natural disasters, to encourage crop growth or for religious ceremonies. 

Chimu Farming Site Uncovered in Peru

An important archaeological find has been made by researchers from San Marcos University (UNMSM) in the Chicama Valley, located in the La Libertad region.

A new archaeological landscape of the Chimu Culture —between 500 and 600 years old— has been discovered in this area.

San Marcos University reported that the archaeological site discovered in El Oso ravine, within the framework of the Chicama Archaeological Program, is believed to demonstrate the agricultural orientation of the Chimu Culture.

With this discovery, previous research and the San Marcos team suggest that the site was mainly used for agricultural production purposes, which is inferred because the channel that connects the Chicama River waters and various areas of the Moche Valley flows very close to the settlement.

According to Henry Tantalean, the archaeologist leading the San Marcos team, the site belongs to the Chimu period and comprises three buildings that are very similar to one another, albeit on a smaller scale than the Chan Chan citadel.

In addition, he explained that it has around 40 hectares of cultivated fields that used to be irrigated using an ancient technique involving a series of channels.

For her part, archaeologist Carito Tavera affirmed that the importance of this discovery and the interest in continuing the works at the site is because this demonstrates the long tradition of the Chicama Valley to allocate spaces for cultivation and large-scale agricultural production for the sustainability of people in this area of northern Peru.

In this way, the establishment of a settlement in this place shows that the Chimu people were interested in managing the area of the valley and did great construction works to expand their agricultural frontiers, something that they are doing even nowadays.

During the excavation process, after removing large rocks, archaeologists found traces of what was a great wall —at least two meters high— that surrounded the site, as well as a fairly preserved and compacted floor covered with sand that the wind brings.

Children’s Teeth Reveal Breastfeeding Practices in Ancient Peru

For thousands of years, breastfeeding habits have remained almost unchanged in the Peruvian Andes, according to an unprecedented research project at an archaeological site in Caral, the oldest civilisation in the Americas and the origin of Andean culture.

There, in a cemetery filled with the bodies of children believed to be buried around 500 B.C., researchers discovered that the way these kids were breastfed was akin to how mothers do it in modern-day rural communities in the Andes.

Tooth analysis of the remains of 48 children showed that the majority were breastfed exclusively for the first six months and were not completely weaned until 2.6 years of age, which is still the case in the most rural and traditional Andean populations.

“We expected a younger age, like in modern times, where due to work issues and social pressures, children are weaned practically at 9 months,” Luis Pezo-Lanfranco, the Peruvian bioarchaeologist leading the study, tells Efe.

Pezo-Lanfranco says that it is very likely intermittent breastfeeding occurred in Caral, the civilization that developed 130 kilometres (over 80 miles) north of Lima between the years 3,000 to 1,800 B.C.

To be sure, researchers need to find a cemetery from that period. A few burial sites from that time in Caral have been recovered but the preservation of bones was too poor to find stable isotopes of carbon, nitrogen and oxygen, which reveal breastfeeding patterns.

Researchers are nevertheless confident that those breastfeeding habits found in infants buried in Chupacigarro ravine cemetery, just a kilometre from the sacred city of Caral, were inherited from the Americas’ first civilization.

“In Caral, many cultural forms were created that are traditional for the Andes,” says Pedro Novoa, deputy director of Caral research and conservation of materials.

While the discovery of a cemetery that would confirm the Caral researchers’ hypothesis has evaded them, indications of the significance that breastfeeding held in this primitive society have been found in several nearby urban centres.

It can be seen in a series of clay statuettes representing women breastfeeding their infants and others who hold their babies in their laps, in an allegory of motherhood discovered in Vichama, one of Caral’s 12 urban centres.

According to the study, it is still not clear whether that long breastfeeding period was a nutritional supplement or was due to food shortages.

Ruth Shady, the director of Caral archaeological investigations, says the high infant mortality may have been due to drought and famine.

“The drought is the main problem they faced, and it is very possible that this was what caused death among these children,” adds Shady, who has been studying Caral since 1994.

Peru: Skeletal remains of 25 people found at Chan Chan archaeological site

According to an Andina report, the remains of 25 people and some 70 artefacts and ceramic vessels have been uncovered in a raised area near the southern wall at Chan Chan, the 1,100-year-old Chimu capital on the coast of northern Peru. 

It was located in Trujillo Province (La Libertad region) – archaeologists behind this important find have reported.

According to Jorge Meneses —head of the archaeological research project— this find is unusual due to its characteristics and location in a raised area of ​​the Utzh An (Great Chimu) walled complex.

“Most of them (the remains) belonged to women under 30 who were buried with objects used in textile activities, a couple of children, and a couple of teenagers.

It is a very specific population, not too young considering the average human lifespan was 40 years, “I have remarked.

Meneses said that this discovery took place three weeks ago during the fourth season of works on the southern wall at Chan Chan. 

The skeletal remains were found in an area of ​​10 square meters, arranged in two levels of the embankment, along with approximately 70 vessels and objects used in textile work.

Burial place for Chimu elite

For her part, Sinthya Cueva —head of the Chan Chan Archaeological Research Program— confirmed that the discovery took place three weeks ago and may have been a burial place for members of the Chimu elite.

“This is something new to us because, in spite of this, we are finding individuals and not simple ones, but of a more relevant category due to the number of objects placed with them as an offering. We may be walking over more remains, “Cave stated.

“We have found several individuals in the western part (of the site) since 2020, and we expect to continue to do so across the eastern sector in the coming seasons. That’s why we suggest that all this raised area could be a pre-Hispanic cemetery, “she added.

Workers digging gas pipes in Peru find the 2,000-year-old gravesite

The AFP reports that workers laying a new gas pipe in the La Victoria district of the city of Lima discovered a 2,000-year-old grave containing some 40 ceramic vessels.

Workers laying gas pipes on a street in the Peruvian capital Lima stumbled on the remains of a pre-Hispanic gravesite that included 2,000-year-old ceramic burial vessels, an archaeologist said Thursday.

“This find that we see today is 2,000 years old,” archaeologist Cecilia Camargo told AFP at the site.

“So far, there are six human bodies that we have recovered, including children and adults, accompanied by a set of ceramic vessels that were expressly made to bury them.”

Experts believe the site in the Lima district of La Victoria may be linked to the culture known as “Blanco sobre Rojo,” or “White on Red,” which settled on the central coast of Peru in the valleys of Chillon, Rimac and Lurin, the three rivers that cross Lima.

“So far, we have recovered about 40 vessels of different shapes related to the White on Red style,” said Camargo, head of the cultural heritage department at the natural gas company Calidda.

“Some bottles are very distinctive of this period and style, which have a double spout and a bridge handle,” Camargo said.

As finds of ancient artefacts and remains occur frequently in Peru, all public service companies that do excavations have in house archaeologists, including Calidda, a Colombian-funded company that distributes natural gas in Lima and in the neighboring port of Callao.

New Horrifying Secrets of Peru’s Ancient Civilizations Unearthed in The Andes

The foothills of the Andes mountains are revealing their bloody secrets: the ancient skeletons of sacrificed children. Archaeologists have unearthed 29 human bodies entombed approximately 1,000 years ago at Huaca Santa Rosa de Pucalá, an archaeological site in the Lambayeque region of northwestern Peru.

Four of the skeletons – belonging to two children, a teenager and one adult – date to the Wari culture.

These four skeletons represent the region’s first known examples of human offerings from the Wari civilization, Edgar Bracamonte Lévano, the excavation’s director and research archaeologist with the Royal Tombs of Sipán museum, told Live Science in an email.

In addition to human remains, the excavation uncovered skeletons from eight guinea pigs, as well as several alpacas and llamas, all of which were likely sacrificed. They also uncovered pots, bottles, and a knife with a half-moon-shaped blade.

Bracamonte Lévano recognized the tombs as Wari because they were surrounded by three distinctive, D-shaped enclosures typical of the culture’s religious spaces.

The human offerings may have been “part of a possible ritual carried out at the time of starting the construction of these Wari-style religious spaces,” he said.

In addition to the four human offerings, the archaeological team uncovered a fifth individual who had undergone secondary burial. “That is to say, he was buried elsewhere and [then] reburied inside the D-shaped enclosure,” Bracamonte Lévano said.

The Wari civilization flourished along the mountains and coasts of modern-day Peru from around AD 500 to 1000.

Wari people were known for their finely woven textiles and sculpted pottery, as well as their roads and terraced agriculture, according to the World History Encyclopedia. These roads would later be incorporated into parts of the Inca Empire.

While the exact structure of Wari society remains open to debate, archaeologists have found evidence suggesting that religion was deeply intertwined with politics and that women were included at the highest levels of governance, as Live Science previously reported.

The other 25 skeletons found buried – though not sacrificed – at the site belonged to the Mochica, or Moche, culture. This civilization thrived in what is now Lambayeque from around AD 100 to 700, and would later be supplanted by the Wari.

READ ALSO: RED PAINT ON THE 1,000-YEAR-OLD GOLD MASK FROM PERU CONTAINS HUMAN BLOOD PROTEINS

Unlike Wari art, which tends toward abstract shapes and patterns, Moche art is famous for its more literal, naturalistic style. That makes artefacts from the two cultures easily distinguishable, Bracamonte Lévano said. 

Among the most significant Moche discoveries in recent years is the Lady of Cao mummy, a tattooed noblewoman whose forensic reconstruction was the subject of a 2017 National Geographic documentary.

The Lord of Sipán, another famous Moche mummy discovered in 1987, resides in the Royal Tombs of Sipán Museum under Bracamonte Lévano’s watchful eye. 

Red paint on 1,000-year-old gold mask from Peru contains human blood proteins

Thirty years ago, archaeologists excavated the tomb of an elite 40–50-year-old man from the Sicán culture of Peru, a society that predated the Incas. The man’s seated, the upside-down skeleton was painted bright red, as was the gold mask covering his detached skull.

Now, researchers reporting in ACS’ Journal of Proteome Research have analyzed the paint, finding that, in addition to a red pigment, it contains human blood and bird egg proteins.

The Sicán was a prominent culture that existed from the ninth to 14th centuries along the northern coast of modern Peru.

During the Middle Sicán Period (about 900–1,100 A.D.), metallurgists produced a dazzling array of gold objects, many of which were buried in tombs of the elite class. In the early 1990s, a team of archaeologists and conservators led by Izumi Shimada excavated a tomb where an elite man’s seated skeleton was painted red and placed upside down at the centre of the chamber.

The skeletons of two young women were arranged nearby in birthing and modifying poses, and two crouching children’s skeletons were placed at a higher level.

Among the many gold artefacts found in the tomb was a red-painted gold mask, which covered the face of the man’s detached skull. At the time, scientists identified the red pigment in the paint as cinnabar, but Luciana de Costa Carvalho, James McCullagh and colleagues wondered what the Sicán people had used in the paint mix as a binding material, which had kept the paint layer attached to the metal surface of the mask for 1,000 years.

To find out, the researchers analyzed a small sample of the mask’s red paint. Fourier transform-infrared spectroscopy revealed that the sample contained proteins, so the team conducted a proteomic analysis using tandem mass spectrometry.

They identified six proteins from human blood in the red paint, including serum albumin and immunoglobulin G (a type of human serum antibody). Other proteins, such as ovalbumin, came from egg whites. Because the proteins were highly degraded, the researchers couldn’t identify the exact species of bird’s egg used to make the paint, but a likely candidate is the Muscovy duck.

The identification of human blood proteins supports the hypothesis that the arrangement of the skeletons was related to a desired “rebirth” of the deceased Sicán leader, with the blood-containing paint that coated the man’s skeleton and face mask potentially symbolizing his “life force,” the researchers say.

The authors do not acknowledge any funding sources.

The abstract that accompanies this article is available here.

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