Question

Fossils found in rock are older/younger than the surrounding rock. (circle one)
What two conditions must be met for a fossil to be considered an index fossil, like ammonites?
1.

2.

Answer 1

Fossils found in rock are **younger** than the surrounding rock. (circle one)

The two conditions that must be met for a fossil to be considered an index fossil, like ammonites, are:

1. The organism lived during a relatively short and specific time period in geological history, making it useful for dating the rock layers.

2. The organism must be widely distributed geographically, allowing it to be found in many different locations and rock formations.