Table 1 Numbers of species used in the Table 2 calculations of “highly conservative” and “conservative” modern extinction rates based on the IUCN Red List (17).

For the highly conservative rates, only species verified as “extinct” (EX) were included; for the conservative extinction rates, species in the categories “extinct in the wild” (EW) and “possibly extinct” (PE) were also included.

Vertebrate taxonNo. of species, IUCN 2014.3
Highly conservative
rates (EX)
Conservative rates
(EX + EW + PE)
No. of species
evaluated by IUCN
Since 1500Since 1900Since 1500Since 1900
Vertebrates33819861747759% (39,223)
Mammals773511169100% (5,513)
Birds1405716380100% (10,425)
Reptiles218372444% (4,414)
Amphibians343214814688% (6,414)
Fishes666615815838% (12,457)