Antarctic area

This zoogeographical area is mainly formed of the continent the Antarctic, but one attaches to it some islands of the high latitudes of the Southern hemisphere, and the Antarctic influences it can be felt on the fauna of the even tropical moderated mediums of this hemisphere.

The Antarctic continent

With a very hard climate, a covered surface of ice and a very rare vegetation (primarily made up of Lichen S and Foam S; the presence of Herbe is exceptional), only highly specialized animal species live this area.

The fauna of the dry land is very reduced: certain zoological groups (Reptile S, Batrachian S…) are completely absent, and the others are represented by a limited number of species, especially of the invertebrates of very small size (Collembole S, Ver S…).

However, marine water shelters a very rich life, with a abundant Plancton, at the base of a complex Food chain, which goes up until the marine mammals (among which several species of Baleine S), and allows the establishment of a large fauna, made up of some species of Oiseau X (Manchot S, Pétrel S, Labbe S) and marine mammals (Phoque S), which comes to reproduce on the dry land, not far from the coasts. These species have important manpower in general, the more so as the human pressure is rather low compared to other continents (the antarctic ecosystem S remain however among most fragile of the sphere).

Subantarctic islands

A certain number of islands of the Antarctic Oceans (Falklands, Crozet, Kerguelen, etc…) is attached to the Antarctic area. If their climate is less hard, there particularly remains cold and been windy, and the situation of insulation of these grounds (sometimes to several thousands of kilometers of the continent nearest) allows only the installation of resistant organizations.

The vegetation is limited to some species (Mousse S, Lichen S and Herbe S thrives and covers the ground of a vast rather uniform carpet), and the fauna of terrestrial invertebrates is rather poor fact there (a little less than in the Antarctic even) and highly specialized (abundance of the apterous shapes of insects), but the richness of the marine animal-life allows the life of abundant colonies of Manchot S, Albatros, Phoque S and Otarie S.

The Antarctic influence on the moderate and tropical latitudes

A fauna with antarctic affinities can be noted on the southernmost coasts of the Australia, of the South America and the South Africa, because of the cold currents (current of Humboldt, of Benguela…), which brings the sea life of the Antarctic Ocean until relatively low latitudes.

The coasts of these countries accommodate colonies of some species of Otarie S ( Otaria and Arctocephalus sp. ) and of Penguin S ( Spheniscus sp. ), less abundant than in the Antarctic and on the sub-polar islands which surround it.

In the extreme case, this fauna goes up until the latitude of the equator, with the presence of these species until the Galapagos Islands, presence made possible by the current of Humboldt!

However, it is about a limit of surface of distribution, and fauna " antarctique" who lives on these territories undergoes with difficulties the climatic accidents (" type; El Nino "), which disturbs the flow of the marine currents and the marine animal-life, without speaking about the warming of planet. Certain species saw their manpower falling, like the Manchot of Humboldt of the Peruvian and Chilean coasts, whose manpower dropped by 12000 to 3300 birds between 1996 and 1997.

Passed and future

The Antarctic seems a desert frozen and inhospitable for the majority of the living beings but it always was not thus. The continent, resulting from the Gondwana, was covered with Forêt S and was populated of a rich person fauna during the Mesozoic , then it gradually overlapped with ice by deriving towards the Southern at the end from the Eocene , to take the aspect which we know.

From here a few tens of million years, the Antarctic plate will go up towards the Northern , and will be according to any probability colonized by a fauna and a flora of the even tropical moderated areas.

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