Question

Question 16

1 pts
Describe one of the extinction events in our geologic history. In your description,
describe what type of life forms were wiped out and the most accepted theory of the
cause.

Answer 1

Answer and Explanation:

The Cretaceous–Paleogene extinction, which occurred around 66 million years ago, is defined as a mass extinction that wiped out around three-quarters of species on Earth.

Among the organisms that disappeared during this event, we find mammals, birds, fish, sharks, pterosaurs, birds, reptiles, insects, and some plant species.

This event is marked by the presence of a sediment layer known as the K-Ph boundary which showed important levels of iridium, an element that is abundant in craters. Therefore, after its discovery, scientists hypothesize this extinction occurred due to the impact of the giant Chicxulub crater which changed the conditions of the atmosphere.