Food chains already under strain before asteroid hit, study
shows
Man's exploitation of resources and reliance on monocrops
could place humans in similar danger
The mass extinction of dinosaurs by a massive asteroid was
made worse because it destroyed the fragile food chain, lessons that modern man
should learn, a study warned.
More than 65million years ago a mountain-sized asteroid
plunged into the earth in Mexico wiping out many species including the
dinosaurs and ending the Cretaceous Period of Earth history.
The study found the food chain was already under strain
before the asteroid hit and could not cope with the cataclysm as plant life
died off.
journal reference (abstract free): pnas >>