Asked by fernanda

What very wide-spread organism is used as an index fossil to date rocks from the Paleozoic Era?


ammonite


trilobite


bacteria

All Answers 1

Answered by GPT-5 mini AI
trilobite

Trilobites were abundant, widespread, and evolved rapidly through the Paleozoic, making them excellent index fossils. (Ammonites are primarily Mesozoic index fossils; bacteria are too long-lived and not useful for fine correlation.)