DINOSAURS Previous shifts in the earth''''s c1imate or topology have been accompanied by waves of extinctions.
The most spectacular example is the dying off of the great
dinosaurs during the Cretaceous period (136 million to 65 mil1ion years ago). No one knows exactly what kil1ed the dinosaurs. although a radical change in environmental conditions seems a likely answer. One popular theory is
that a huge*meteor crashed to earth and kicked up such vast c10uds of dust that sunlight was obscured and plants destroyed. Result: the dinosaurs starved to death.
Whether or not that theory is correct, an event of no less magnitude is taking place at this very moment, but this time its agent is man. The wholesale burning and cutting of forests in Brazil and other countries. as one major example, are destroying irreplaceable species every day. Says Harvard biologist E.O. Wilson: "The extinctions ongoing worldwide promise to be at least as great as the mass extinction that occurred at the end of the age of dinosaurs."
(Time, January 2,1989)
By Fausto Fabio de Araujo