Trilobites are generally considered to be older than brachiopods in terms of their evolutionary history. Trilobites first appeared around 520 million years ago during the early Cambrian period and thrived for nearly 270 million years until their extinction during the Permian mass extinction, around 250 million years ago. On the other hand, brachiopods appeared slightly later in the fossil record, around 500 million years ago, also during the Cambrian period. They continued to diversify throughout the Paleozoic era and can still be found in the present-day oceans, although their diversity has significantly declined compared to their peak in the past. Therefore, trilobites have a longer geological history and are generally considered to be older than brachiopods.
