Trilobite fossils are easily recognized and can be very beautiful
Trilobites were in abundance during the Paleozoic era particularly around 540 million years ago during the Ordovician and Cambrian periods where large numbers flourished in the oceans. The trilobite families continued to grow until the Late Cambrian when some type of event wiped out a large number. During the end of Ordovician, ice sheets spread toward the equator during a great ice age. This ice age removed many more of the Trilobite families.
Those trilobite families that were able to survive into the Silurian era had transformed into exotic and new forms, and became even more exotic looking during the Devonian era. The rising seas during the Devonian era caused havoc on the trilobite reef system habitat and forced them into forced selective adaptation.
Only one trilobite order survived the mass extinction of the Devonian era. Though the Carboniferous era only saw the Proteus trilobite order survived, this one order branched off and evolved to form similar appearances to the trilobites that fell to extinction. Even with this adaptation trilobites were not able to recover to previous numbers during the Carboniferous era, and only a small number were able to survive into the Permian era. This was mostly due to the trilobites’ failure to adapt to new deep-water environments. They also proved unable to handle the dramatic climate changes, and basically disappeared during a mass extinction as the Permian era closed. There are some modern insects that have similar characteristics to trilobites that have been labeled as trilobite imposters.
- Late Devonian: mass extinction or mass invasion? (earth-pages.co.uk)
- ScienceShot: Hide and Seek in the Cambrian (news.sciencemag.org)
- Fossils show shrimp-like superpredator’s eyes had 32,000 lenses (csmonitor.com)