Trilobites on the sea bed


Palaeontologists have identified more than 20,000 different trilobites, an amazingly diverse group of animals. They all lived in the sea: some burrowed in the mud, some crawled on the surface of the seabed and others swam about in open water or inhabited reefs. Although some types of trilobites were blind, most had well developed eyes with very sophisticated lenses that had a great depth of field. Some species had eyes on stalks and these are believed to have buried themselves in the mud, with only their eyes sticking out like periscopes.

Scientific name: Trilobita

Rank: Class

Common names:

three lobes

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The following habitats are found across the Trilobites distribution range. Find out more about these environments, what it takes to live there and what else inhabits them.


Discover what these behaviours are and how different plants and animals use them.

Additional data source: Animal Diversity Web

When they lived

Discover the other animals and plants that lived during the following geological time periods.

What killed them

Permian mass extinction Permian mass extinction
The Permian mass extinction has been nicknamed The Great Dying, since a staggering 96% of species died out. All life on Earth today is descended from the 4% of species that survived.

Fossil types

Learn more about the other animals and plants that also form these fossils.

Fossil Folklore

Trilobites have featured it our folklore - learn more our ancestors beliefs before we understood fossilisation and evolution.


  1. Life
  2. Animals
  3. Arthropods
  4. Trilobites

BBC News about Trilobites

  • Trilobite was ancient snack food Direct evidence has been found that trilobites, the most diverse animals in the fossil record, were eaten by other ancient sea creatures.