Mary Allen
Introduction: The Trilobite’s Longevity
Trilobites are one of the most fascinating groups of extinct marine arthropods that lived from the Early Cambrian to the end of the Permian period, about 540 million to 250 million years ago. Throughout their existence, trilobites underwent significant morphological changes in response to environmental pressures and natural selection. Despite these changes, one characteristic remained constant in some trilobite taxa. In this article, we will explore which characteristic did not change over time and its significance in the evolutionary history of trilobites.
The Anatomy of a Trilobite
Trilobites were a diverse group of arthropods that had a unique body plan consisting of three distinct body regions: the cephalon (head), the thorax (body), and the pygidium (tail). They also had a hard exoskeleton made of calcium carbonate that protected their soft internal organs from predators and environmental factors. Trilobites had a wide range of sizes, from a few millimeters to over 70 centimeters in length. Their eyes were one of their most distinctive features, which could be compound or simple, and sometimes developed into elaborate structures. Trilobites were also able to molt their exoskeletons throughout their life, which allowed them to grow and repair any damage to their protective coating.