Man-induced changes in biodiversity since the end of the last Ice Age:
Hunting pressure caused the demise of large mammals at the end of the Ice Age and was the beginning of the considerable influence of man on biodiversity. The destruction of habitats started with the clearing of forests, even in Europa. Today, tropical rain forests are destroyed along with their unique communities and species richness.
The driving force behind the clearing is the expansion of agriculture and livestock. Another threat to biodiversity is the use of insecticides and other pesticides, and too many fertilizers, resulting in monocultures in agriculture. Agriculture is considered the »No. 1 Killer« of biodiversity.
Man has widely altered the species composition in the sea and on the land through global trade and exchange of plants and animals. Other species such as weeds are introduced with the importing of crops. Meadows and fields now look similar worldwide. In the sea many stocks of commercial fish species are overfished.
Millions of animals are killed every year as fishing by-catch. Since there is no market for them, these mainly dead animals are returned to the sea. The Fishing is considered the »No.2 Killer« of biodiversity.