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Fossil with petrified flower

Patagonian flora and fauna

During the five-year voyage around the world on bord the HMS Beagle and, in particular, during the time of his stay on the American Continent between 1832 and 1835, Charles Darwin explored the coasts and mountains of Patagonia, while the captain and cartographer Robert Fitzroy remained near the coastline to measure the depths of the seas, explore navigable channels, and study the strong currents of the southern ocean. Darwin took advantage of those long periods the HMS Beagle remained in the southern channels to explore the Patagonian region by land, which enabled him to gather useful anthropological and geological material, as well as zoological information in the shape of a collection of animal species, while also undertaking paleontological scientific research.

He studied the ‘Falkland Islands Wolf,’ which was apparently twice the size of an English fox, and was also variously known as the ‘Falkland Island Dog,’ ‘Falkland Island Fox,’ ‘Antarctic Fox’ or ‘Warrah.’ Darwin also studied Toxodon fossils from an extinct herbivore very similar to a rhinoceros and found skeletal remains for a Macrauchenia (a three-toed South American ungulate mammal), and a Mastodon (which had a similar weight to elephants), as well as horse fossils with shorter and wider legs. His research also makes reference to his discovery of a Glyptodont, a Megatherium and a Mylodon. His observations regarding climate and the glaciers led him to measure and relate these formations to the glaciers that existed in Europe.

According to Darwin, the southern-most glacier moving towards the sea in the Northern Hemisphere was located on the coast of Norway, at the northern latitude of 67° and was twenty degrees closer to the North Pole than the glacier of Lake San Rafael in Chilean Patagonia in relation to the South Pole. This is a difference of 1,980 km between the two hemispheres, from which one can deduce that, already, during the time of the voyage of the HMS Beagle in 1834, the phenomenon of global warming was being observed occurring naturally for the first time. The northern hemisphere demonstrated this symptomatic decline and Darwin noted that the southern hemisphere was a great deal colder, with differences in the extent of its glacial regions that varied from the European ones by as much as 2,000 km.

Darwin contributed to our knowledge of the elements such as the coastal climate for the Straits of Magellan. He climbed Mount Tarn that rises 825 m above sea level and his account of the ascent to the summit is highly descriptive. Darwin relates in his diary for Patagonia that the vegetation at the start of the expedition was very bushy and, as they made their ascent, they saw rotting trees spread out in all directions and experienced forceful gusts of wind and a terrible cold that barely allowed them to stand up while they observed the snowy mountains and a large part of Tierra del Fuego.

He collected and studied edible mushrooms and observed the native trees and marine plants, gathering all his notes into his writing and later using them to develop his theory of evolution, publishing his famous books after he completed his journey to the Galapagos Islands and finished analyzing all the investigations he had undertaken during his voyage around the world. His controversial book On the Origin of Species was published in 1859.

Flora

The flora of this region is highly diversified and ranges from the Andean-Patagonian forests to the semi-desert vegetation of the extreme south of the American Continent. Its flora survives on the highland plains of the Altiplano, where it is exposed to the predominant arctic winds, which dehydrate the atmosphere in the region, resulting in a great scarcity of trees.

However, abundant native forests can be found, predominantly in the north of continental Patagonia, between the Patagonian Mountains and the Pacific Ocean, where they are located in the valleys near lakes. These forests can also be found in the bays at the openings of the system of fjords, beginning by the Guaitecas Islands in the south, and reaching Golfo de Penas (Gulf of Sorrows) and its glaciers. This is primary forest, commonly known as Valdivian temperate rainforest, and it owes its survival and natural reproduction in particular to the predominant rains of the regions near the Pacific Ocean, and to the humid saline climate that spreads into the valleys of the Patagonian Mountain.

The range for this dense forest is defined by the area immediately adjoining the Andes to the east, with its volcanoes and ancient glaciers, and the Pacific Ocean to the west. Similarly, there is a very humid forest on the eastern slopes, which has a wealth of native species, even while the eastern region of the Patagonian Mountains has scarce native species, and is predominantly covered by the plains of the Argentine Pampa in Southern Patagonia.

The main body of Valdivian temperate rainforest is found on the continental section of Patagonia and, in particular, in the north; while to the south, on the mainland and along the fjords, the Magellan subpolar forests are encountered.

The Valdivian temperate rainforest is mostly comprised of species such as the roble southern beech (Nothogagus oblicua) and the lenga (Nothogagus pumilio); as well as the Antarctic beech (Nothofagus antartica), and an abundant presence of mosses and a variety of fern species, such as Blechnum chilensis and Lophosoria quadri-pinnata. Also present are the ulmo tree (Eucruphia cordifolia), the laurel-leaved tineo (Weinmannia trichosperma), the canelo (Drimys winteri), and the Chilean myrtles arrayán (Luma apiculata) and melí (Amomyrtus meli). Among the conifers found is the cypress tree of the Guaitecas Islands (Pilgerodendron uviferum) and the mountain cypress (Austrocedrus chilensis).

The archipelago of the Guaitecas Islands is composed of a coastal shelf made up of an area of uniformly flat islands, such as those found throughout the fjords of Norway and Sweden; and all over that region of Patagonia there is an abundance of the Patagonian cypress tree known as alerce (Fitzroya cupressoides).

In the Magellanic Island sector, there is a predominance of native tree species, such as the ñirre and the lenga, which are found on the high plains, and also Magellan’s beech tree (Notofagus betuloides). Among the Magellanic forests, one can equally spot the native canelo (Winter’s Bark) and the red willow, which are also present along the rivers Río Colorado, Río Negro, Río Calle-Calle and Río Chubut.

On the side of the southern Atlantic and certainly in the Magellanic Forest, one can find species of halophiles (salt-loving plants), in the shape of sparse, low-lying plants; and also the algarrobillo flowering tree (Prosopis affinis) and the piquillin shrub. On the plains, there are various plant species that grow no higher than 50 cm, which take the shape of cushions as a result of the ferocious winds prevailing in the south-east. In general, the transition of the Andes Mountain Range exhibits distinct forests: moist forests stretching down to the Pacific Ocean, and more arid vegetation towards the Atlantic Ocean.

Fauna

As regards the fauna of the Patagonian region, there is an acknowledged presence of condor, puma, guanaco, huemul, fox, nandu and pudu –although this last species is only found in small numbers; and birds, such as the chucao that live exclusively in the Patagonian forests.

Chucao

Cóndor

The mountain cat, the nandu and the fox are present in the Southern Patagonian region and on the Argentine pampa. Along the coasts, there are penguins, two species of sea lions (the common Patagonian sea lion Otaria flavescens and the South American fur seal Arctocephalus australis), as well as various species of whales.

The most common of Patagonian fauna that exemplifies the regional wildlife is the guanaco (Lama guanicoe), and also the Andean condor (Vultur gryphus), the largest airborne bird in the world, which unifies the Andean cordillera by its presence throughout its length, all the way to the Patagonian Mountains in the south.

During his journey on the HMS Beagle to Patagonia between August 1832 where he reached the mouth of Río Negro until February 1835 when he sailed from Valdivia to Concepción after the big earthquake. Charles Darwin undertook an exhaustive study of both the condor and the guanaco and provided a very good description of the movements of the former in its mountain habitat with this quote:

Charles Darwin

“When the condors are wheeling in a flock round and round any spot, their flight is beautiful. Except when rising from the ground. I do not recollect ever having seen one of these birds flap its wings... they moved in large curves, sweeping in circles, descending and ascending without giving a single flap... The head and neck were moved frequently and apparently with force... If the bird wished to descend, the wings were for a moment collapsed; and when again expanded with an altered inclination, the momentum gained by the rapid descent seemed to urge the bird upwards with the even and steady movement of a paper kite....it is truly wonderful and beautiful to see so great a bird, hour after hour, without any apparent exertion, wheeling and gliding over mountain and river.”

Regarding the propagation and feeding habits of these birds, Darwin wrote:

“With respect to their propagation, I was told by the country people in Chile that the condor makes no sort of nest, but in the months of November and December lays two large white eggs on a shelf of bare rock... Certainly along the Patagonian coast, there cannot be any kind of nest among the cliffs where one can observe the youngest fledglings perched on their feet... The condors may oftentimes be seen at a great height, soaring over a certain spot in the most graceful circles. On some occasions I am sure that they do this only for pleasure, but on others, the Chileno countryman tells you that they are watching a dying animal, or the puma devouring its prey. If the condors glide down, and then suddenly all rise together, the Chileno knows that it is the puma which, watching the carcass, has sprung out to drive away the robbers. Besides feeding on carrion, the condors frequently attack young goats and lambs; and the shepherd dogs are trained, whenever they pass over, to run out, and looking upwards to bark violently.”

Darwin, C. The Voyage of the Beagle, Complete and

Unabridged, London, Mentor paperback, 1988.

In relation to the guanaco Darwin wrote:

“The guanaco, or wild llama, is the characteristic quadruped of the plains of Patagonia; it is the South American representative of the camel of the East. It is an elegant animal in a state of nature, with a long slender neck and fine legs. It is very common over the whole of the temperate parts of the continent, as far south as the islands near Cape Horn. It generally lives in small herds of from half a dozen to thirty in each; but on the banks of the St Cruz we saw one herd which must have contained at least five hundred.”

Guanacos from an illustration dating from the explorations by Darwin in 1834.

In relation to their exploitation by the native people Darwin added:

“These animals are very easily domesticated, and I have seen some thus kept in northern Patagonia near a house, though not under any restraint. They are in this state very bold, and readily attack a man by striking him from behind with both knees. It is asserted that the motive for these attacks is jealousy on account of their females. The wild guanacos, however, have no idea of defence; even a single dog will secure one of these large animals, till the huntsman can come up. In many of their habits they are like sheep in a flock. Thus when they see men approaching in several directions on horseback, they soon become bewildered, and know not which way to run. This greatly facilitates the Indian method of hunting, for they are thus easily driven to a central point, and are encompassed.”

Darwin, C. The Voyage of the Beagle, Complete and

Unabridged, London, Mentor paperback, 1988.

Manuscript page from Charles Darwin’s Theory of Evolution