Signal Extinction rate above 100 per million species-years against a boundary of 10

Summary

The species extinction rate, a provisional proxy for genetic diversity in biosphere integrity, now exceeds 100 extinctions per million species-years, with the 2026 assessment range reaching 100 to 1000. The natural background rate is estimated at about one, the boundary is set tenfold higher at 10 and the high-risk line lies at 100. One unit means one species out of a million disappearing each year. Cumulative records since 1500 show at least 73 vertebrate genera lost over the past 500 years, and complementary estimates for vertebrates and some land invertebrates point to rates of up to 100. The main causes are the spread of cropland and grazing into intact nature, the fragmentation it brings and direct exploitation such as fishing and logging, with climate change, pollution and invasive species adding pressure. The report worries that this loss erodes the biosphere's resilience and its ability to buffer other boundary transgressions.