Why Earth Stopped Building Monsters ?

For most of Earth's history, being enormous was the winning strategy. The air was so rich in oxygen that dragonflies grew the wingspan of a bird of prey and centipedes reached the length of a grown man. Then the vertebrates took the idea further. On land, herbivores hollowed their own vertebrae into air-filled chambers so their skeletons could carry the weight, and cracked their tails through the air at supersonic speed. The hunters answered with serrated teeth the size of railroad spikes and bites measured in thousands of pounds per square inch. The oceans went further, because water carries what bone cannot. Long-necked hunters looked like a serpent threaded through the body of a giant turtle. Overhead flew animals as tall as a giraffe, with skulls over nine feet long, launching into the air off all four limbs. Bone fused into helmets over the skull, tails ended in clubs that could snap a predator's leg, and horned herds locked into circles with the young inside. Then the volcanoes opened, the climate began to swing, and being enormous became the thing that killed them. So what does it take to build a monster - and why did Earth stop making them? Settle in for the full story, and subscribe for more documentaries on Earth's deep past. #PrehistoricMonsters #Dinosaurs #Documentary the age when monsters ruled everything, prehistoric monsters, dinosaur documentary, prehistoric animals, full documentary, prehistoric earth, age of dinosaurs, science documentary, nature documentary, documentary, dinosaurs, when dinosaurs ruled the earth, extinct animals, giant prehistoric animals,