Humans are reproducing at a rapid rate that is becoming difficult for the environment to support.
Pollution contaminates natural ecosystems and again poses a threat.
Often habitats are demolished, for example to make way for buildings and roads. A specific type of habitat loss is deforestation, or cutting down trees.
If you introduce an animal that did not evolve along with the natural surroundings, it could have terrible effects on the other species in the area.
Destruction of natural habitats in order to extract minerals or clear land for farming. This displaces a lot of animal species and destroys whatever cannot run away from this invasion.
Overkill Excessive hunting of any one species can throw the food chain way off course.
