Museum Collections and Research
Prehistoric Specimens
Background Knowledge
This artist's rendering depicts a creature that lived as early as 400 million years ago, the Trilobite.
So far in this resource kit you've looked at ways of preparing "extant" or living species. But Field Museum is also home to hundreds of thousands of fossil specimen, like the trilobite fossils pictured below! These fossils can be used to glimpse into the living world of the past. Comparing the morphology and structure of extant species and extinct can provide important insights into the ecosystems of the past!
Can you think of any animals you've seen that resemble the organisms in these fossils? Take a spin through these images to learn more!
Trilobites are an extinct group of arthropods and possessed a head, thorax and tail. Exceptionally-preserved trilobites also show legs and antennae. Isopods, commonly known as sowbugs or pillbugs, are a modern arthropod that resembles trilobites in many ways.
All trilobites lived in seawater. Most were crawlers upon the seafloor, and some could also swim through the water or burrow into sediment. Since trilobites are extinct, interpretation of their feeding habits is difficult. Many may have been scavengers of dead organisms, and some may have been predators, grazers, or filter-feeders.