Many scientists agree that most dinosaurs went extinct when an asteroid struck Earth about 66 million years ago. Ancestors of modern birds survived the asteroid impact, then rapidly diversified as they filled new niches and the niches left by dinosaurs. Most modern groups of birds had evolved by 35 million years ago.

Question

Since this time, the rate at which birds have diversified into new species has increased. Scientists have found that particularly high rates of speciation occurred in regions where mountains have recently formed. New species evolved as birds already present on these mountains became specialized to habitats that developed as mountains grew.

Which statement does this information best demonstrate?
A.
The formation of new niches can cause sudden or gradual geological disturbances that influence the evolution of life on Earth.
B.
Gradual geological events, like mountain formation, decrease the diversity of life on Earth.
C.
Catastrophic events, like asteroid impacts, are mainly responsible for the evolution of life on Earth.
D.
Both gradual and sudden geologic disturbances contribute to the diversity of life on Earth by allowing new niches to form.

Answer 1

The statement that this information best demonstrates is:

D. Both gradual and sudden geologic disturbances contribute to the diversity of life on Earth by allowing new niches to form.

This choice encompasses the idea that both the catastrophic event of the asteroid impact and the gradual formation of mountains have led to the creation of new niches, which in turn has allowed for increased diversification of bird species.