In September 1832, during the first year of its mission, the Beagle anchored near Bahía Blanca, a settlement at the head of a bay about 400 miles southwest of Buenos Aires. A certain General Rosas was waging a genocidal war against the Indians, and Bahía Blanca stood as a fortified outpost, occupied mostly by soldiers. For more than a month the Beagle remained in that area, some of its crew occupied with surveying, others assigned to shore duties—digging a well, gathering firewood, hunting for meat. The landscape round about was classic Argentine Pampas, fertile grassland, giving way to grass-anchored sand dunes along the coast. The hunters brought back deer, agoutis, and other game, including several armadillos and a large flightless bird Darwin loosely called an "ostrich." Of course it wasn't an ostrich (which is native to Africa, and formerly the Middle East); it was a rhea, specifically Rhea americana, ostrichlike in appearance but endemic to South America and the heaviest bird on the continent.
"What we had for dinner to day would sound very odd in England," Darwin wrote in his diary on September 18, reveling in the exoticism of his new regimen: "Ostrich dumpling & Armadilloes." He was out for a romping adventure, not just a natural history field trip, and his shipboard diary (later transformed into a travel book that came to be known as The Voyage of the Beagle) reflects his attention to cultures, peoples, politics, as well as to science. The red meat of the big bird resembled beef, he recorded. The armadillos, peeled out of their shells, tasted and looked like ducks. His culinary experiences here on the Pampas, and later in Patagonia, besides being part of his voracious tour of discovery, would eventually play a role in his evolutionary thinking.
A few days afterward, on September 22, 1832, Darwin and Fitzroy took a small boat to visit a site called Punta Alta, ten miles from their anchorage, where they found some rocky outcrops overlooking the water. "These are the first I have seen," Darwin wrote, "& are very interesting from containing numerous shells & the bones of large animals."
Despite the name, Punta Alta ("high point") was not very high, its reddish mudstone cliff rising only about 20 feet. But if the headland wasn't dramatic, the exposed fossils were: big shapes, unusual shapes, and abundant. Darwin and a helper went to work on the soft rock with pickaxes. Between that session and later efforts, he harvested from Punta Alta the remains of nine great mammals, all unknown or barely known to science. They were extinct Pleistocene giants, unique to the Americas in an age sometime before 12,000 years ago.