August 9, 2002

Humans, Alas, May Survive the Next Mass Extinction

To the Editor:

Malcolm G. Scully's review of "eco-optimism" (represented by Bjørn Lomborg) and pessimism (represented by Michael Boulter) raises intriguing questions about whether extinctions prompted by man's global activities will fit the patterns of the "Big Five" mass-extinction events documented in the fossil record ("In the Long Run, or Maybe Sooner, We're Extinct," The Review, July 5).

Mass extinctions appear to result from major climatic changes or catastrophes,