Half a billion years in the making, these are some of the most exquisite trilobite fossils that I have ever seen. You can almost imagine that these little animals are still alive and still crawling along some ancient ocean seabed. They hail from the Cambrian Period, when the Earth was still mostly covered with water. They lived for 300 million years, before going extinct. Throughout their evolution, trilobites exhibited most lifestyles expected of modern marine arthropods, including acting as predators, scavengers and filter feeders. Their name, trilobite means three-lobed. Those are not antenna, but rather eye stalks, which may have been used to poke through covering sand. Trilobites had highly advanced eyes for their time. These were compound eyes, similar to that of modern insects.