Biodiversity is essential in medicine as most active chemicals used to make medicines are derived from plants or other organisms. Climate change today threatens species that are vital to medicine. An example would be coral reefs. Studies have been done on reefs that look at fighting cancers, HIV and other ailments. One of the richest zones of biodiversity is the tropics and this region is under threat from global warming and deforestation. It is important to preserve these species for use in future medicinal research.