Index fossils come from types of organisms that lived during only a relatively short period of time, were abundant, and were widespread geographically. Index fossils can therefore used to determine the relative age of rocks found in
different areas. Index fossils help to match
A)
fossils from land and sea.
B)
rock layers from different areas.
plants to the animal life that ate them
D)
sedimentary rocks with igneous rocks formed at the same time.