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Transcript of Disappearing Dinosaurs
Peeking through the branches, you see the tree is on the edge of a large clearing. In the clearing, there a several brachiosauruses. Into the clearing rambles a spiky backed dinosaur, the stegosaurus. Soon after, a triceratops appears. You peak around behind the tree, tipping so hard you almost fall out.
You hear a loud "ROAR!!" and the earth begins to tremble. In a split second, a Tyrannosaurus Rex comes barreling into the clearing, chasing all other creatures out. You shrink back into the tree and soon enough the T-Rex goes away. Phew! That was a close call! The dinosaurs roamed for around 140 MILLION years. That's a long time. The dinosaurs were still roaming 70 million years ago, (which is even before your GREAT GRANDMA was born!) but they mysteriously died off. Know one knows the real answer to this question, but scientists have some theories. When the Dinosaurs Roamed Some of the theories that scientists have come up with are a little weird. Some say the dinosaurs were abducted by ALEINS! Others say that the dinosaurs were killed by diseases, or worldwide flooding. Other scientists say that dinosaurs evolved into birds when the continents (which was once a "supercontinent") split apart. Yet others say that mice-like creatures would sneak into the dinosaurs' nests and steal their eggs, so they eventually died off. Crazy Theories! A Dusty Theory Evidence Of An Asteroid Introduction Probably the most popular theory is that an asteroid hit earth. When the asteroid hit, it would've sent up a huge dust cloud that blocked out the sun. Without the sun, plants wouldn't be able to grow. Without the plants, plant-eating dinosaurs would have no food and they'd die. Without them to eat, meat-eating dinosaurs would also die. But why do scientists think this?
This theory is supported by the volcanic eruption of KRAKATOA, which erupted in 1883. When this occured, darkness covered the sky for a full day, and temperatures evrywhere dropped. This could likely be what happened to the dinosaurs. The evidence of this theory is pretty clear. In 1978, geologist Walter Alvarez was in a deep valley studying rocks. Since the valley was so deep, it showed layers of Earth's history of it's walls.
Many layers were the same, containing tiny shells left behind by creatures that lived millions of years ago, called forams. But one layer was different. It had no forams. The layer after that was different, too. It only had shells of one kind of foram. Between these layers was a thin line of clay.
Scientists say this clay was formed by the dust that had covered the sun and eventually settled, creating clay. Luis and Walter Alvarez Tyrannosaurus Rex Triceratops Could OUR species be wiped out? While scientists say it IS possible for another asteroid to hit earth, they have a theory to when. Scientists believe that asteroids only strike every 28 million years.
This theory sounds a bit befuddled to me because dinosaurs were have said to rule the world for 140 million years. Maybe the asteroids that hit while the dinosaurs lived were small, except for the last one. Conclusion How dinosaurs disappeared is a big mystery that boggles peoples' minds all the time. There a dozens of theories, but earth being hit with an asteroid is hugely agreed on.
Scientists are constantly looking for more evidence of the crash and until they find it, the people of earth will be stumped.
So, how do YOU think dinosaurs disappeared? Gigantoraptor Supersaurus Stegosaurus