#kuelap

Map of sampling locations and approximate distribution of sub-branches of the Quechua language family, as traditionally classified. Red dot 1 marks the sampling locations in the Amazonas region (Chachapoyas City, Luya, Huancas, Utcubamba South, La Jalca); red dot 2 marks that in the San Martín region (Lamas, Wayku neighbourhood). The inset zooms in on the sampling locations in Amazonas. Credit: Barbieri et al. Enclaves of genetic diversity resisted Inca impacts on population history. Scientific Reports, DOI: 10.1038/s41598-017-17728-w.

"By targeting various linguistic indicators, we were able to pinpoint a genetic signal in Chachapoyas that turned out to be far more diverse than we expected, especially in the male line, from father to son," explains Chiara Barbieri, a geneticist at the Max Planck Institute for the Science of Human History in Jena, Germany, and lead author of the study. "First of all, there's still a strong surviving Native American component, despite all the admixture with European genes ever since the Spanish conquest. What's more, here the native component is quite different from the main genetic network in the highlands of central and southern Peru. This is where the Inca Empire and its predecessors originated, and their conquests, road networks and empire-building ended up homogenizing the genetic make-up here." The current study reveals how the people of Chachapoyas, by contrast, remained relatively isolated. "So it seems that some genetic legacy of the Chachapoyas did indeed resist Inca impacts, all the way through to today," explains Barbieri.

Two Peruvian geneticists, José Sandoval and Ricardo Fujita of the Universidad San Martin de Porres in Lima, Peru, also took part in the study. "These latest samples are part of a wider genetic coverage of Peru that we've been building up for years. It's these groups like the Chachapoya, culturally and linguistically highly distinctive, who have the most to tell us about our ancestors: where they came from, where they migrated to, what interactions they had with each other, and so on. Also, the Chachapoyas culture left such extensive archaeological remains that there are good prospects for recovering ancient DNA, to complement the modern picture."

Paul Heggarty, a linguist and senior author of the study, also of the Max Planck Institute for the Science of Human History, was first motivated to launch this project after unexpected results from a linguistic fieldwork trip to Chachapoyas. He was able to find a few remaining elderly speakers of an indigenous language that most assumed was already extinct in this region. "Quechua is one of our most direct living links to the people of the New World before Columbus. It still has millions of speakers, more than any other language family of the Americas - but not in Chachapoyas anymore. There are only a dozen or so fluent speakers now, in a few remote villages, so we need to act fast if we're to work out its real origins here."

The body-shaped sarcophagi of Karajía contained the remains of high-ranking Chachapoya ancestors. The inhabitants of Chachapoyas today may in part descend from these pre-Inca populations. Credit: Chiara Barbieri

The Chachapoyas form of Quechua has usually been classified as most closely related to the Quechua spoken in Ecuador, but the new DNA results show no close connections between the Quechua-speakers in these two areas. "Linguists need to rethink their traditional view of the family tree of Quechua languages, and the history of how they spread through the Andes," notes Heggarty. "It seems that Quechua reached Chachapoyas without any big movement of people. This also doesn't fit with the idea that the Incas forced out the Chachapoyas population wholesale."

Jairo Valqui, another linguist co-author from the National University of San Marcos in Lima, adds a further perspective on an even earlier language layer. "Once Quechua and Spanish arrived, the local Chachapoyas languages died out. Recovering anything from them is a real puzzle and a challenge for linguists. They left very few traces, but there are some characteristic combinations of sounds, for example, that still survive in people's surnames and in local placenames, like Kuelap itself."