Short answers, pulled from the story.
The Norte Chico civilization, also known as Caral-Supe, on the north-western coast of present-day Peru is the oldest civilization in the Americas, dating back to about 3500 BC. It was one of the first six civilizations to develop independently in the world and predated the Mesoamerican Olmec by nearly two millennia. It is believed to have been the only civilization dependent on fishing rather than agriculture to support its population.
Some of the oldest evidence of human presence in South America comes from the Monte Verde II site in Chile, dated to around 14,500 years ago. People reached the Americas from eastern Asia by crossing the Bering Land Bridge into present-day Alaska, then spread south over millennia.
The Inca civilization dominated the Andes from 1438 to 1533 from its capital at the puma-shaped city of Cuzco, calling its realm Tawantin suyu, the land of the four regions. It reached nearly a hundred linguistic or ethnic communities, some 9 to 14 million people, connected by a 25,000-kilometre road system. The Inca had no written language but recorded information using quipu, a system of knotted strings.
The Muisca were one of the four grand civilizations in the Americas, inhabiting the Altiplano Cundiboyacense in the Eastern Ranges of the Colombian Andes, with a population estimated between 300,000 and two million. Known as The Salt People for their halite trade, they were the only pre-Columbian civilization in South America known to have used coins, called tejuelos. Their gold and tumbaga work created the legend of El Dorado.
European diseases such as smallpox, influenza, measles, and typhus were the overwhelming cause of depopulation among native peoples who had no resistance to them. Estimates of population decline range from 20 to 50 percent at the low end to as high as 90 percent. Forced labor systems like the encomienda and the mining mita deepened the loss, after which enslaved Africans were brought in to replace the dead.
The pink tide refers to the perception that leftist ideology became increasingly influential across Latin America in the 21st century. Cristina Fernández de Kirchner described Hugo Chávez of Venezuela, Luiz Inácio Lula da Silva of Brazil, and Evo Morales of Bolivia as the three musketeers of the left. By 2005 the BBC reported that three out of four of South America's 350 million people lived in countries ruled by left-leaning presidents.