PT38 S1 Q9 Some scientists believe that..

mitrakhanom1

When I read the question I assumed that the debris hurled into the atmosphere causing the blocking of the sun and extinction of the dinosaurs was only in the Yucatan Peninsula. Which is why answer choice B was attractive and I picked it rather than answer choice E. I understand why E is correct, but can somebody explain why or how I should have assumed the debris from the asteroid was around the world versus just affecting the Yucatan Peninsula?

Hibiscus

I think you're a bit confused about the stimulus. The discrepancy in this stimulus is that the asteroid wiped out all of the dinosaurs, but the debris settled too quickly for food sources to disappear and for the dinosaurs to freeze.

From this discrepancy, we know that we have to identify a reason why the dinosaurs were driven to extinction, and that reason must be caused by the asteroid.

B actually doesn't resolve anything, since the stimulus states that the asteroid caused the extinction of dinosaurs. If B were true and there were dinosaurs around the world, the question of how they were all wiped out still exists since their food sources are still there and they have not frozen to death.

E states that the dinosaurs were killed from fatal respiratory problems resulting from contamination of the air caused by the asteroid debris, which would solve the discrepancy.

Also, since the asteroid debris would have been in the atmosphere for 6 months and blocked out sunlight to kill off all dinosaurs, you would probably assume that the debris is able to cover every location with dinosaurs. As a result, you would also assume that contamination would spread to every dinosaur as well.