November 1, 1993 (September 18) ����, American scientists have suggested that the extinction of the dinosaurs new to say. November 1, 2011,

1993 (Lssdjt.com) scientists of the U.S. Geological Survey Department in a seminar held by the American Geographical Society, presented new evidence, the reasons for the extinction of the dinosaurs 65 million years ago, Earth's atmosphere The oxygen content decreased, rather than an asteroid or meteorite impact on Earth's momentum. Geological Survey Department,
a group of scientists led by Gary Landis amber fossil remains of ancient times, the gas bubble analysis found that the age of the dinosaurs, the oxygen content in the atmosphere between 200 million to 300 million years from highest when 35% is reduced to 28%.
Landis said, the oxygen content in the atmosphere is only 21%, but the rate of decline in the oxygen content of the dinosaur era than scientists originally envisaged 10 to 20 times higher than the survival of all animals and plants constitute a huge pressure. In his view, the extinction of the dinosaurs is not a short period of time event, but 100 million years of the long process.