Keystone Ecology Practice Test

An endangered species is defined as a species that is at risk of extinction due to a variety of factors, which can include habitat loss, climate change, pollution, disease, and overexploitation. This classification is used to identify those species that are facing significant threats and require conservation efforts to prevent their numbers from declining further.

The term "endangered" specifically indicates that there is a high risk of extinction in the near future, making it crucial for conservation, legal protection, and recovery initiatives to be put in place. Monitoring and protecting endangered species is essential for biodiversity, as they often play crucial roles in their ecosystems.

In contrast, options that suggest a species is increasing in population, newly discovered, or fully adapted to its habitat do not align with the definition of endangered. These terms do not convey the urgent need for protective measures that accompany the status of being endangered.