In some instances a major natural event, such as a volcanic eruption, can kill an entire isolated species. In other cases, extinction will happen slowly as nature changes the world. For example, the dinosaurs disappeared because of a change in Earth's climate, and they could not survive the changing temperatures. Increased human population growth causes problems for other life on this planet. As the human population grows, an increasing number of species become extinct.
People change the habitats , or homes, upon which living creatures depend.
Rapid development has destroyed or altered many of the natural environments to which individual species are adapted. When humans pollute, spray pesticides, use toxic chemicals, introduce non-natives species or poach, their actions affect what happens to other living things. There are also plant and animal species that are generally referred to as candidate species. Scientific data exists to indicate candidate species populations are not stable, and, in some cases the viability of that species is in question.