What do scientist use trilobites as proof of

Trilobites are known as index fossils, fossils used by scientists to make inferences on the ages of rock layers. "Trilobites allow geologists to date the rocks they are found in and correlate them with other rocks of similar ages around the world," Dr.

Because they appeared quickly in geological time, and moulted like other arthropods, trilobites serve as excellent index fossils, enabling geologists to date the age of the rocks in which they are found. They were among the first fossils to attract widespread attention, and new species are being discovered every year.