Together plants and animals form a food chain, which is kept stable by complex inter-relationships between the many species in a local habitat. The loss of biodiversity threatens all remaining species, including humans. A living species becomes extinct when the last known individual dies. But a species needs a minimum number of individuals to ensure enough genetic diversity for continued survival. Once the number of individuals drops below that number, the species is doomed to extinction.
Habitat loss is the number one cause of extinction.
Once a species is reduced to a small population in a limited area, the species becomes much more vulnerable to disease outbreaks or natural disasters. Furthermore, many species fail to reproduce when numbers drop below the minimum number for species survival. Threatened species can be recovered through habitat protection and research into causes and solutions for population decrease. You can do your part to protect threatened and endangered species in your area by learning to identify those species, learning what their habitat needs are, and protecting or creating habitat for those species.