Have you ever heard of a trilobite before? Well if you've ever seen them...it's probably been in fossil form! Trilobites are actually a group of fossils - the fossils of an extinct group of marine arthropods. They look similar to horseshoe crabs or almost alien like with all their creepy crawly limbs. In fossil records, Trilobites helped define the Early Cambrian period - roughly 521 million years ago! Trilobites disappeared during the mass extinction at the end of the Permian period - 252 million years ago...along with 96% of all other life on our planet! Surviving that long was no easy feat for sure, but it makes Trilobites one of the most successful early animals, surviving throughout the oceans for 270 million years.
Trilobites help us learn a lot from these long ago prehistoric times. They had a wide diversity of organisms, and their exoskeleton was easily fossilized leaving a lot of good remains for us to research. Studying these fossils has lead to many contributions in the fields of evolutionary biology, plate tectonics, paleontology, and more! It is believed that Trilobites were exclusive marine organisms, as their fossilized remains are always found in rocks containing other salt water creatures. Their remains are found worldwide, with thousands of varying species, and were among the very first fossils to receive widespread attention.