Geez, where do I even start with trilobites?!
They are my favorite animal and my favorite fossil to work with. I find them to be very adorable and endlessly interesting. I could go on and on about why they are so dang cool, and I probably will in future posts, but let's start with the basics today and I will save the deep dives for another time.
An array of Elrathia kingii trilobite fossils used in my latest collection.
Trilobites are an extinct type of ocean dwelling arthropods; animals with no back bones that have a hard exoskeleton, segmented bodies and jointed legs.* There are over TWENTY THOUSAND different species of trilobites found in the fossil record!
Wow, let’s just take a moment to dwell on that…
Clearly this was a very diverse group of animals, but for the most part they follow a pretty simple body plan, a half moon shaped head section and a segmented body with three distinct lobes, hence “tri - lobe - ite”! There are however, some really extreme variations on this body plan as well including spiky armor, forehead tridents, and towering eyes! The different species ranged in size from 3 millimeters up to 72 centimeters. All these different body variations means that they had a good variety of lifestyles and habitats. Some swam, some inched along the ocean floor, some even crawled out onto land. Some lived in shallow seas, some lived in deep waters. They hunted, they scavenged, they filter fed. They did it all!
A trilobite from the order proetida, the original I used to make the Iapetus Ring.
Trilobites first appear in the fossil record a whopping 521 million years ago in the Early Cambrian. These little creepy crawlies lived on Earth for almost 300 million years, the last of them died out in the Permian Extinction about 252 million years ago. 300 million years is a pretty dang impressive amount of time for a group of little beasties to survive, making trilobites some of the most successful animals ever!**We know a lot about trilobites because we have found a lot of trilobites. They were marine animals with a hard exoskeleton which is kind of the ideal situation if you want to become a fossil. Additionally, they are found worldwide, so paleontologists all across the globe have access to them. Unfortunately, the vast majority of trilobite fossils that we find are just the exoskeleton, not the soft under-parts. There are a few rare instances when soft body preservation is found however, and even a few fossils with eggs preserved!
A pyritized trilobite fossil from Gold Bugs showing preserved legs and antenna!
Another cool thing about having a segmented exoskeleton….you can roll that thing up when you feel threatened! I find this so endearing, rolly trilobites are my favorite trilobites! Being able to protect your tender belly is such a great defensive mechanism, and the way they clamp up so neatly is quite satisfying!
Three views of an enrolled Eldredgeops trilobite from Ohio. Pic by fossilera.com
I will stop my trilo-gushing at that, but if you want to learn more, I have a couple book recommendations.*** First is one of my favorite popular science books ever. Trilobite! by Richard Fortey**** is really thorough but an easy and fun read. I’ve read it at least three times now and will probably give it another go soon. Number two is a bit spendy, so I’d try your local library first or see if you can do an interlibrary loan, but if you want to buy it I think it’s worth every penny! The Trilobite Book, A Visual Journey by Riccardo Levi-Setti is full of gorgeous photos and loads of knowledge. It’s like having a museum quality collection of trilobites at home.
If I haven’t convinced you that trilobites are The Best just yet, I plan on getting into the nitty gritty in future posts. In the mean time if you’d like to check out what trilobite pieces I have in the shop you can click here to see work I’ve made with the actual fossils, and here for the cast fossil collection.
Thank you as always for your interest and your time,
*Insects, spiders and crustaceans are also arthropods.
**From what I can tell, horseshoe crabs (who aren’t actually crabs) are in the #1 slot for longest surviving species at 445 million years and counting! But guess who they are related to.….trilobites!
***Which I know you will buy from independent book sellers only :)
****I am a fan of all of Fortey’s books. Earth is another one I like to re-read from time to time.