Our knowledge of biodiversity is still limited. Only one out of five to ten of all species is known to science. And even among the most well-known taxonomic groups - mammals, birds, amphibians, reptiles and vascular plants - we do not know the population size, distribution or threat status for many. We still have many questions about the inherent dynamics of ecosystems and their functioning and cannot predict when gradual impact on an ecosystem reaches a threshold at which the state of the ecosystem changes dramatically and irreversibly.
To address these questions the Convention calls upon countries to identify components of biological diversity important for its conservation and sustainable use. It also indicates which components countries might need to focus on when designing biodiversity monitoring programmes:

• Ecosystems and habitats containing high diversity, large numbers of endemic or threatened species, or wilderness; required by migratory species; of social, economic, cultural or scientific importance; or, which are representative, unique or associated with key evolutionary or other biological processes;
• Species and communities which are threatened; wild relatives of domesticated or cultivated species; of medicinal, agricultural or other economic value; or social, scientific or cultural importance; or importance for research into the conservation and sustainable use of biological diversity, such as indicator species; and
• Described genomes and genes of social, scientific or economic importance.

Moreover, the Convention encourages countries to maintain and organize biodiversity information to facilitate future analyses and assessments. More »