Trilobites at the Chicago Field Museum

Museums can make great places for social outings, but I also love going to them alone.  I can skip the uninteresting parts and obsess as much as I want over the good parts.  On a recent trip with friends to the Field Museum a few weeks ago, the miles of enticing, juicy exhibits drove me mad with unsatisfied curiosity.  So I went back by myself and spent an entire day!

Who knew trilobites had such amazing appendages?

There was so much to see, but my absolute favorite was their collection of exquisitely articulated trilobite fossils.  Trilobites were among the earliest Arthropods, which are the jointed-appendaged animals like insects, spiders and roly-poly bugs.  They were commonly-fossilized animals from about 525 million years ago through 250 million years ago, which is an astonishingly long period of time in evolutionary history.

Trilobites are so much cuter with antennae.

I'm not sure how these fossils were separated from their surrounding rock, but their details are incredible.  Looking at these fossils, I could imagine these little critters skittering across the ocean floor and using those appendages to sense water movement and scent of prey items.

Trilobite diversity.

The exoskeleton of trilobites was thick and tough, which made it easier for fossils to form.  Scientists have been able to study the evolution of eye structures, other sense organs and delicate feeding apparatuses over time using trilobites.  There was considerable diversity of trilobite species.  It is not understood why trilobites went extinct.  Their closest living species relative alive today is probably the horseshoe crab.

A trilobite called Walliserops with what has to be a smell/taste organ on its front end.