A Cretaceous-Tertiary mass extinction?  Were most of Earth's species killed off?
Briggs
J C
JC
Department of Marine Science, University of South Florida, St. Petersburg, FL 33701, USA.
D000818:Animals; D005075:Biological Evolution; D002980:Climate; D018534:Earth, Planet; D017753:Ecosystem; D005580:Fossils; D008386:Marine Biology; D010163:Paleontology; D010944:Plants; D016082:Solar System; D013997:Time Factors; D018707:Volcanic Eruptions