Imagine how the Conquistadores (and Vikings!) felt to find themselves pursued by tyrannasurs. This would certainly put a crimp in their plans. Not until the 19th century when machine guns were invented, (which may have been invented sooner.) that exploration could take place. And maybe not until the 20th century when aeroplanes came along. Imagine flying (from Cuba, say, where dinosaurs couldn't reach) and strafing tyrannasurs for a living--and they can't shoot back. Comments?