It&#x27;s interesting because so much genetic diversity was lost after the conquest:<p>&gt; Llamas is not surprised that a potentially common pre-Columbian genetic group all but disappeared after the Spanish arrived. “Up to 90% of native South Americans died very quickly” after the conquest, mostly from epidemic disease, he says. “You can imagine that a lot of genetic diversity was lost as well.” Especially in the Americas, where such an extreme demographic collapse was followed by centuries of mixing by European, Amerindian, and African groups, the genes of living people “aren’t always a faithful representation of what happened in the past,” Salas says. The Aconcagua boy’s genome, on the other hand, is “a window to 500 years ago.”