A bar chart showing the number of species evaluated for extinction risk in 2025 across various taxonomic groups.

Horizontal bar chart depicting species evaluated for extinction risk by taxonomic group.

Number of species evaluated for their level of extinction risk, 2025 The number of species in each taxonomic group evaluated for their extinction risk level is a small share of the total number of known species in many taxonomic groups. Our World in Data Fishes 29,114 Insects 13,696 Birds 11,185 Reptiles 10,368 Molluscs 9,502 Amphibians 8,051 Mammals 6,036 Crustaceans 3,361 Arachnids 1,053 Corals 916 Data source: International Union for Conservation of Nature Red List of Threatened Species (2025) OurWorldInData.org/biodiversity | CC BY