Scientists found many different types of fossils in a rock layer, which was dated at 251–299 million years old using an index fossil. In layers directly above that point, scientists found a large decrease in the number of fossils, particularly of marine and insect fossils. When did the extinction event occur?

i think it is due maybe a lack of food for animals on land.

Explanation:

It did not affect the water animals because they had food underwater. i don't know when it happened but just google your question.

would the answer be physical geography and cultural geography i haven't studied geography but i searched it online and those are my answers.

hope this .

plz mark me as brainliest answer: d