Global Actions Cause Local Consequences
The world's ecology is so complex, so fragile, so interdependent, that an ecological upheaval of the flora and fauna of one region of the world (i.e. the destruction of rainforests) can affect the entire planet.
Global trade has introduced species to areas outside of their natural habitat, where there are no predatory species to control their destructive habits.
Fire ants were brought to the United States in a cargo ship. They have caused the death of livestock, people, and many native species of ants and insects.
You need look no further than Florida to see the importance of native flora and fauna on the local ecosystems.
Plants like Kudzu, Brazilian Pepper, Australian Pine, and Chinese Tallow were brought in from other countries to the United States and have invaded and destroyed entire habitats of native flora. The Everglades is being destroyed by Malaleuca, which was seeded by airplanes to dry up the Everglades and allow sugar cane to be planted after the Cuban embargo.
The introduction of non-native brown anoles and Cuban tree frogs into Florida has nearly caused the extinction of native lizard and toad species, which are their prey. Iguanas and other large lizard species, as well as large snakes such as boas and pythons, are invading the Everglades and other ecologically sensitive areas.
In fact, Florida and its port cities have introduced and become invaded by more invasive non-native species than any other state in the U.S.
Imports of salmonid eggs into Japan have caused outbreaks of disease into several of their native fish species, causing great economic and ecological losses.
The list goes on indefinitely. The University of Arizona site tells a shocking tale of the ecological and economic cost of invasive flora and fauna to the U.S. alone every year.