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 taxon	No. of species, IUCN 2014.3
	Highly conservative rates (EX)		Conservative rates (EX + EW + PE)		No. of species evaluated by IUCN
	Since 1500	Since 1900	Since 1500	Since 1900
Vertebrates	338	198	617	477	59% (39,223)
Mammals	77	35	111	69	100% (5,513)
Birds	140	57	163	80	100% (10,425)
Reptiles	21	8	37	24	44% (4,414)
Amphibians	34	32	148	146	88% (6,414)
Fishes	66	66	158	158	38% (12,457)