Consequently, sea creatures such as trilobites, brachiopods, and graptolites became extinct. Fossils found in the sedimentary rocks in the park include algae, brachiopods and trilobites. Shelled molluscs therefore predate the earliest trilobites. Major losses were experienced by brachiopods, fishes, echinoids, sponges and trilobites. Fossils and imprint trails of trilobites and brachiopods have also been found in the Tapeats. Brachiopods, bryozoa, molluscs, hederelloids, tentaculitoids, crinoids and trilobites were abundant and diverse. Fossils of fish, corals, trilobites, etc. Trilobites and brachiopods in particular were rich and diverse. Chitin was probably present in the exoskeletons of Cambrian arthropods such as trilobites. Plants like algae evolved, and the fauna was dominated by armored arthropods, such as trilobites. Climate was warm and invertebrates, such as the trilobites, were abundant. Trilobites, which are now extinct, had unique compound eyes. Such creatures are found in the fossil record and include lingulata, trilobites and worms. The placement of the extinct trilobites is also a frequent subject of dispute. Some other later trilobites also lost facial sutures secondarily.