The Beagle left Santiago and sailed towards Brazil (Bahia and Rio de Janeiro). Darwin spent the days exploring the tropical rain forests on long walks, taking in the rich magnificence of nature. He described the scene as beautiful beyond his wildest dreams. Darwin collected many good specimens of plants, insects and animals during this trek and recorded them in his specimen lists and zoology notes. Then he shipped off his load of specimens and notes to Henslow back in Cambridge. All specimens were numbered, catalogued and described.
"It was impossible to wish for any thing more delightful than thus to spend some weeks in so magnificent a country. In England any person fond of natural history enjoys in his walks a great advantage, by always having something to attract his attention; but in these fertile climates, teeming with life, the attractions are so numerous, that he is scarcely able to walk at all."
The Beagle arrived at Montevideo. Darwin spent many weeks collecting fossils in Patagonia, and found huge fossil bones in a cliff. Darwin knew very little about paleontology, but he figured any fossils he collected may be of some interest to the experts back in England. When Darwin came back onboard Capt. FitzRoy had a difficult time understanding why he was bringing all sorts of "useless junk" on the ship. This collection consisted of the fossil bones of giant ground sloth, giant animal who was similar to a hippopotamus or a rhinoceros, giant armadillo, giant animal who was similar to a camel. Darwin wondered why the fossils resembled the present inhabitants of that continent more than any other species. The burning question remained - how did the animals become extinct? These fossils proved that very many creations had occurred in different geological eras. Also he collected a large number of exotic animals, birds, and reptiles, and saw many herds of ostrich on the pampas. Darwin sent a load of specimens to Henslow in Cambridge. This shipment included: eighty species of birds, twenty quadrupeds, four barrels of skins and plants, geological specimens and some fish.
The Beagle arrived at the Falkland Islands. Darwin went on shore and spent the next few weeks engaged in fossil collecting. One thing that caught Darwin's attention was how different the fossils on the island were from those he found on the coast of South America. During his stay at the Falklands Darwin decided to do comparative studies between all the fossils, plants and animals he collected during the voyage. Such studies would later influence