title: How much do we know about the current extinction rate?
abstract: Since about J600, 486 animal species have been recorded extinct. This represents about 0.04% of all animal species so far described. In the same period, 600 plant species are known to have disappeared, about 0.25% of the total. These figures are much smaller than those of the Permian/ Triassic and Cretaceous/Tertiary mass extinctions. One might therefore conclude that at present life on earth is at comparatively little risk of extinction. However, there is a growing body of data to show that the converse is true.
authors.affiliation: Fraser Smith and robert May are at the Dept of Zoology, University of Oxford, South Parks Road, Oxford, UK OX1 3PS.
authors.forename: F D
authors.initials: FD
authors.lastname: Smith
authors.forename: R M
authors.initials: RM
authors.lastname: May
authors.forename: R
authors.initials: R
authors.lastname: Pellew
authors.forename: T H
authors.initials: TH
authors.lastname: Johnson
authors.forename: K R
authors.initials: KR
authors.lastname: Walter