Sustainability

The disappearance of species

An animal species is seriously threatened with extinction when its population is broken up. Extinction is a natural process that may be caused by natural selection, shortage of food or natural calamities. It has been calculated that 9 species out of 10 of those that have appeared on Earth over the centuries have disappeared. Man's action on nature has also caused entire animal species to disappear over the years. Hunting, deforestation, pollution, the conversion of uncultivated areas into pastures, the illicit trade of wild animals as well as climatic changes have made life difficult for many animals. The areas that have been hit hardest by the rise in the Earth's temperature are the Arctic and the oceans. In these places, animals suffer because they have lost their habitat and find it hard to find food to eat. This results in a decrease of births and therefore in the slow disappearance of some species. In the oceans, the reduction of plankton caused many types of fish to migrate and many invertebrate organisms to disappear.