Pre-Columbian people in the Atacama raised parrots for their feathers

Centuries ago, indigenous South Americans brought live parrots hundreds of kilometers across the Andes Mountains, then raised them in captivity in the Atacama Desert, according to a recent study.

The Atacama is one of the last places you’d look for tropical parrots. It’s the world’s driest desert, and it stretches along the Pacific coast of Chile to the west of the Andes Mountains. Most communities in the Atacama are hundreds of kilometers from the nearest place a tropical bird might find livable. But Pennsylvania State University archaeologist Jose Capriles and his colleagues recently examined the skeletons and mummies of 27 Amazonian parrots, representing at least six species, that had been buried as funeral offerings for the dead at several pre-Columbian sites in the Atacama.

They found that the birds had most likely been kept in captivity and plucked often for their bright red, yellow, blue, and green feathers. To get to the desert, the birds must have been captured in their tropical Amazon habitats and carried across the Andes along trade routes. Captured parrots probably arrived on the llama caravans that frequented oasis communities like Pica, in northern Chile.

Exotic trade goods

Communities like Pica grew around oases that once formed the nodes of a vast network of llama caravan routes that connected the Atacama with communities far away in the Amazon basin and beyond. Pica, in the dry heart of the Atamaca, was a regional trade hub from the 900s to the 1400s CE, so it was well-established by the time the Inca conquered the region in the 1470s. And the most important of Pica’s residents—and those of similar Atacama communities—were often buried with rich grave goods, including parrots.

The mummified birds were usually set in a resting position but occasionally were posed in dramatic style with their beaks opened wide and their tongues sticking out. The researchers studied the chemistry of their bones for clues about the birds’ diets and examined their remains for clues about how they had lived and been cared for.

They concluded that most of the birds had been kept in captivity in the desert oasis communities, were often fed diets based on maize, and were frequently plucked to harvest their feathers. Keeping the birds alive would have required skilled work, but their presence would have been as much a status symbol as the feathers they provided.

For thousands of years, but especially during the centuries of Tiwanaku and Inca power, political leaders, elite warriors, and priests from several cultures in the Andes and the Atacama wore the feathers of tropical parrots, like the scarlet macaw, as symbols of their status. Headdresses, ornaments, and ceremonial robes have been found in cemeteries and rock shelters across the region, with the earliest example dating back more than 5,000 years.

Parrot farming at the oasis

Several of the birds Capriles and his colleagues studied had been mummified with nearly as much care and ceremony as the humans they accompanied. Because the long-dead parrots’ skin was so well-preserved, the researchers could see that all of them had too many down feather buds. In most birds, that’s a symptom of excessive plucking. The birds could have been pulling out their own feathers, either from stress or illness, but Capriles and his colleagues say it’s more likely that people were regularly harvesting their plumage.

Many of the birds in the study showed other subtle clues that spoke of a life in captivity. One bird’s beak and several birds’ claws were overgrown, while others had clearly been trimmed with tools instead of wearing down naturally as they would in the wild. Another bird’s wing bones had broken and healed, which suggests that it was probably cared for after the injury—and that the injury may have been inflicted by humans trying to keep the parrot from flying away, Capriles and his colleagues speculate. Other birds had clipped feathers on the end of their wings that would have limited their ability to fly.

Capriles and his colleagues also studied the ratios of stable isotopes of the elements nitrogen and carbon in the parrots’ bones. Carbon-12 and carbon-13 ratios can offer clues about the kinds of plants someone ate; nitrogen can suggest how much meat or seafood made up a person’s diet.

Some of the captive parrots had eaten a diet rich in tropical seeds and fruits. But most of the others had apparently been fed a diet based on domestic plants like maize. Some parrots had unusually high levels of nitrogen-15, which probably means that the maize they ate had been fertilized with guano from marine birds. That matches evidence from the bones of people buried in the same region.

New World caravan routes

As the crow—or parrot—flies, the nearest place where all six species live in the same overlapping habitats would be about 500 kilometers away across the Andes Mountains. According to Capriles and his colleagues, however, a complex network of trade routes probably sourced parrots from several different places, some up to 900 kilometers away. That’s about a two- or three-month trip one way, based on modern indigenous people’s experience.

Ancient DNA from the Atacama parrots supports the idea of complex, constantly flowing trade networks. Archaeologists have also found the remains of tropical parrots at the Chaco Canyon site in New Mexico, but those birds all seem to have come from the same fairly small population. That suggests that the rich and powerful at Chaco Canyon imported a single breeding colony of parrots on just one trip.

But in the scattered oasis communities of the Atacama, archaeologists found several species of parrots. And even members of the same species showed an amount of genetic diversity that suggested they’d been sourced from several wild populations at different places and times. It’s not yet clear whether any of those wild-caught parrots were later used to breed new offspring once they crossed the Andes.

We still don’t know if caravans made the whole journey to the Amazon to fetch live parrots and bring them back to Inca territory or if live birds passed from hand to hand along a more complex trading network. But parrots are just one example of the trade in goods across hundreds of kilometers of rugged terrain. The networks stretched from the Amazon basin east to the Atacama and north to the southwestern US. Indigenous people in the Americas have maintained these far-flung networks since centuries before the rise of the Inca Empire, and in many places they still persist today.

PNAS, 2021 DOI: 10.1073/pnas.2020020118  (About DOIs).

https://arstechnica.com/?p=1753032