Chapter 12: Alvarez Theory on Dinosaur Die- Out Upheld

Question 1

According to Yarris, in 2010 an international panel of 41 experts in geology, paleontology and other related fields ruled in favor of the asteroid impact as the reason for the dinosaurs’ extinction. This is a theory first put forth in 1980 by one of Berkeley Lab’s greatest scientists, the late Nobel laureate Luis _______.

Answer 1

Alvarez

Question 2

About 165 million years ago, an event called ______ ______ ______describes a massive extinction of nearly _______ percent of all the species of life on our planet.

Answer 2

The Great Dying, 75

Question 3

Iridium, a silvery-white metal related to ________, is virtually absent from the Earth’s crust, but high concentrations are common in ________ objects, such as _______.

Answer 3

platinum, extraterrestrial, asteroids

Question 4

On the ______ peninsula, the _______impact is regarded as the ultimate cause for the mass extinctions of the dinosaurs.

Answer 4

Yucatan, Chicxulub