From Wikipedia, the free encyclopedia. A teenager, or teen, is a young person whose age falls within the range from 13â19. They are called teenagers because their age number ends with teen. Usage by ordinary people varies, and also varies in different societies.
Astronomers and other scientists often speak of the extinction of dinosaurs on this earth. They believe that dinosaurs disappeared from the earth some 65 million years ago, long before man came along.They make these statements as if it were a known, proven scientific fact that dinosaurs were long gone by the time men appeared on the earth.hey believe that dinosaurs disappeared from the earth some 65 million years ago, long before man came along. They make these statements as if it were a known, proven scientific fact that dinosaurs were long gone by the time men appeared on the earth.
Although the exact origin and timing of the evolution of dinosaurs is the subject of active research, the current scientific consensus places their origin between 231 and 243 million years ago. They became the dominant terrestrial vertebrates after the TriassicâJurassic extinction event 201 million years ago.