title: Species uncertainties.
authors.forename: Robert M
authors.initials: RM
authors.lastname: May
authors.forename: Paul H
authors.initials: PH
authors.lastname: Harvey
mesh_terms: D000818:Animals; D044822:Biodiversity; D002965:Classification; D017753:Ecosystem; D053476:Extinction, Biological; D049810:Genetic Speciation; D010944:Plants / Q000145:classification