South America is incredibly diverse; nowhere else is there such a wealth of wildlife and diversity of creatures living in such a wide range of landscapes. Wherever you go in South America, you’ll find an extraordinary diversity of life. But how did these unique worlds come about?
To understand the natural history of this continent, we must go back to the age of the dinosaurs. Back then, South America was part of Gondwana, a giant continent that included lands that later became Africa, Australia, India, and Antarctica. Reptiles reigned in that world, and descendants of these ancient creatures live in South America to this day. In the forests of southern Chile, plants familiar to the dinosaurs, the tree fern and the strange monkey tree, are still found today.
As time passed, a new group of animals emerged. The first mammals in South America were small in size, and many were marsupials, like the native possum. It lives in the cold, moist forests of southern Chile, preying on insects and earthworms. Another small marsupial inhabiting these ancient forests is the colocolo, or soniferous (Chiloeche) opossum. It is so tiny that it can fit in the palm of a human hand. Colocolo also eats insects, but does not refuse fruit.
When we think of animals with pouches, the first thing that comes to mind is Australian kangaroos. But there are more than 80 species of marsupials in South America, an echo of an ancient era when the two continents were one.
About 100 million years ago, the giant continent of Gondwana began to slowly split apart, and South America became a huge island cut off from the rest of the world. The next chapter in its history is a long era of upheaval that changed the face of the continent forever. Some 80 million years ago the island began to be shaken by volcanic eruptions that continue to this day. The shifts in the depths of the Earth’s crust caused the Andes, a colossal mountain chain, to rise along the length of the continent.
These mountains stretch for more than 8,000 kilometers, the longest mountain chain on Earth. In the north, the slopes are covered by tropical forests, and the peaks are so high that even on the equator they are always covered with snow and ice. In the central Andes lies a high-mountain dry desert, the Altiplano. To the south, the mountains become lower, and we get closer and closer to Antarctica. In the far south, in Patagonia, excluding the polar regions, there is the most extensive area of ice in the world: the ice covers more than 18 thousand square kilometers, and glaciers stretch to the sea.
Animals have managed to adapt even to such conditions. In the shadow of Patagonian ice peaks they have to endure fierce winds and winters with heavy snowfalls. Only the hardiest animals, such as guanacos (South American relatives of camels) and foxes, can survive here. But even they do not easily survive the winter.