The Geology of Europe is hugely varied and complex, and gives rise to the wide variety of landscapes found across the continent, from theScottish Highlands to the rolling plains of Hungary.[126]
Europe's most significant feature is the dichotomy between highland and mountainous Southern Europe and a vast, partially underwater, northern plain ranging from Ireland in the west to the Ural Mountains in the east. These two halves are separated by the mountain chains of the Pyrenees and Alps/Carpathians. The northern plains are delimited in the west by the Scandinavian Mountains and the mountainous parts of the British Isles. Major shallow water bodies submerging parts of the northern plains are the Celtic Sea, the North Sea, the Baltic Seacomplex and Barents Sea.
The northern plain contains the old geological continent of Baltica, and so may be regarded geologically as the "main continent", while peripheral highlands and mountainous regions in the south and west constitute fragments from various other geological continents. Most of the older geology of Western Europe existed as part of the ancient microcontinent Avalonia.
Geological history
Main article: geological history of Europe
The geological history of Europe traces back to the formation of the Baltic Shield (Fennoscandia) and the Sarmatian craton, both around 2.25 billion years ago, followed by the Volgo-Uralia shield, the three together leading to the East European craton (≈ Baltica) which became a part of the supercontinent Columbia. Around 1.1 billion years ago, Baltica and Arctica (as part of the Laurentia block) became joined toRodinia, later resplitting around 550 million years ago to reform as Baltica. Around 440 million years ago Euramerica was formed from Baltica and Laurentia; a further joining with Gondwana then leading to the formation of Pangea. Around 190 million years ago, Gondwana andLaurasia split apart due to the widening of the Atlantic Ocean. Finally, and very soon afterwards, Laurasia itself split up again, into Laurentia (North America) and the Eurasian continent. The land connection between the two persisted for a considerable time, via Greenland, leading to interchange of animal species. From around 50 million years ago, rising and falling sea levels have determined the actual shape of Europe, and its connections with continents such as Asia. Europe's present shape dates to the late Tertiary period about five million years ago.[127]
Biodiversity
See also: Fauna of Europe
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Having lived side-by-side with agricultural peoples for millennia, Europe's animals and plants have been profoundly affected by the presence and activities of man. With the exception of Fennoscandia and northern Russia, few areas of untouched wilderness are currently found in Europe, except for various national parks.
The main natural vegetation cover in Europe is mixed forest. The conditions for growth are very favourable. In the north, the Gulf Stream and North Atlantic Driftwarm the continent. Southern Europe could be described as having a warm, but mild climate. There are frequent summer droughts in this region. Mountain ridges also affect the conditions. Some of these (Alps, Pyrenees) are oriented east-west and allow the wind to carry large masses of water from the ocean in the interior. Others are oriented south-north (Scandinavian Mountains, Dinarides, Carpathians,Apennines) and because the rain falls primarily on the side of mountains that is oriented towards sea, forests grow well on this side, while on the other side, the conditions are much less favourable. Few corners of mainland Europe have not been grazed by livestock at some point in time, and the cutting down of the pre-agricultural forest habitat caused disruption to the original plant and animal ecosystems.
Probably eighty to ninety per cent of Europe was once covered by forest.[128] It stretched from the Mediterranean Sea to the Arctic Ocean. Though over half of Europe's original forests disappeared through the centuries of deforestation, Europe still has over one quarter of its land area as forest, such as the taiga of Scandinavia and Russia, mixed rainforests of the Caucasus and the Cork oak forests in the western Mediterranean. During recent times, deforestation has been slowed and many trees have been planted. However, in many cases monoculture plantations ofconifers have replaced the original mixed natural forest, because these grow quicker. The plantations now cover vast areas of land, but offer poorer habitats for many European forest dwelling species which require a mixture of tree species and diverse forest structure. The amount of natural forest in Western Europe is just 2–3% or less, in European Russia 5–10%. The country with the smallest percentage of forested area (excluding the micronations) is Iceland (1%), while the most forested country is Finland (77%).[129]
In temperate Europe, mixed forest with both broadleaf and coniferous trees dominate. The most important species in central and western Europe are beech and oak. In the north, the taiga is a mixed spruce–pine–birch forest; further north within Russia and extreme northern Scandinavia, the taiga gives way to tundra as the Arctic is approached. In the Mediterranean, many olive trees have been planted, which are very well adapted to its arid climate; Mediterranean Cypress is also widely planted in southern Europe. The semi-arid Mediterranean region hosts much scrub forest. A narrow east-west tongue of Eurasian grassland (the steppe) extends eastwards from Ukraine and southern Russia and ends in Hungary and traverses into taiga to the north.
Glaciation during the most recent ice age and the presence of man affected the distribution ofEuropean fauna. As for the animals, in many parts of Europe most large animals and top predatorspecies have been hunted to extinction. The woolly mammoth was extinct before the end of theNeolithic period. Today wolves (carnivores) and bears (omnivores) are endangered. Once they were found in most parts of Europe. However, deforestation and hunting caused these animals to withdraw further and further. By the Middle Ages the bears' habitats were limited to more or less inaccessible mountains with sufficient forest cover. Today, the brown bear lives primarily in theBalkan peninsula, Scandinavia, and Russia; a small number also persist in other countries across Europe (Austria, Pyrenees etc.), but in these areas brown bear populations are fragmented and marginalised because of the destruction of their habitat. In addition, polar bears may be found onSvalbard, a Norwegian archipelago far north of Scandinavia. The wolf, the second largest predator in Europe after the brown bear, can be found primarily in Eastern Europe and in the Balkans, with a handful of packs in pockets of Western Europe (Scandinavia, Spain, etc.).
European wild cat, foxes (especially the red fox), jackal and different species of martens, hedgehogs, different species of reptiles (like snakes such as vipers and grass snakes) and amphibians, different birds (owls, hawks and other birds of prey).
Important European herbivores are snails, larvae, fish, different birds, and mammals, like rodents, deer and roe deer, boars, and living in the mountains, marmots, steinbocks, chamois among others.
The extinction of the dwarf hippos and dwarf elephants has been linked to the earliest arrival of humans on the islands of the Mediterranean.
Sea creatures are also an important part of European flora and fauna. The sea flora is mainlyphytoplankton. Important animals that live in European seas are zooplankton, molluscs,echinoderms, different crustaceans, squids and octopuses, fish, dolphins, and whales.
Biodiversity is protected in Europe through the Council of Europe's Bern Convention, which has also been signed by the European Community as well as non-European states.
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