Trilobites were exclusively what type of animals?

Trilobites were exclusively marine animals, which is reflected in their evolutionary history and fossil record. They thrived in the oceans during the Paleozoic era, particularly from the Cambrian period through to the end of the Permian period. Their adaptations, including their hard exoskeletons and compound eyes, were well-suited for marine environments, allowing them to occupy various ecological niches, from shallow waters to deeper oceanic regions. The presence of trilobite fossils in marine sedimentary rocks further supports their classification as marine organisms. This distinguishes them clearly from other types of animals that inhabit freshwater, terrestrial, or amphibious environments, which were not characteristics of trilobites.