the trilobite is used as an index fossil for various geologic time periods as specific types of the trilobites were present in different geological time periods. they are a group of marine arthropods belonging to the class of trilobita.
Trilobites were one of the best examples of index fossils because they were present for a relatively shorter period of time and were widely distributed. They were found to be existed only in the Paleozoic era.
The trilobites were efficient in dating rocks in which they were found to be embedded. I helped in determining the age of the rocks. They also provided sufficient data regarding the early climate and the food habitat of these organisms in the past. Thus, these data enabled the Paleontologists to reconstruct the paleoclimate.
These fossils also helped in the correlation of rocks, thereby helping in the field of biostratigraphy
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