010420

Fossil packstone, a mish-mash of broken bits in mud, Mississippian Bangor Ls, 330 myo, thin-section photo, 2.5 mm wide. Trilobite looking like a weird parenthesis in lower center.

From the Brochure

Time travelers to the Cambrian be warned

A shellfish allergy is a big problem

In a time before vertebrates

On the other hand, nothing beats

A Cajun trilobite boil on the beach

Under the swift early Paleozoic sun

040716

Anomalocaris

once thought a weird shrimp

made trilobites squeal like stuck pigs

as it went all Shelob

on their soft bellies

trace fossil paper now out

Geodinamica Acta, containing my paper about a burrow not made by trilobites after all, is now out. The journal is available in print and digitally. This is a special issue derived from an international meeting on trace fossils that was held in Turkey.

http://www.tandfonline.com/toc/tgda20/current

090315

trenchlobites dig small
and few for 200 my
climate change ticket

That must've hurt!

Trilobite tail with a huge bite out of the left side. The critter lived! The bite's partly healed. It's Asaphiscus wheeleri, from the Cambrian Wheeler Shale of western Utah. This is one of my favorites of trilobites I collected from the Wheeler (when I was working on my dissertation on another rock unit out there) because it shows action.

Who attacked a trilobite? The only known candidate is this guy:




This is Anomalocaris, which means weird shrimp. Critter wasn't shrimp, and it was the top predator in the Cambrian. It was a foot long or more and its prey, Cambrian trilobites, were mostly 2 inches or shorter. I am sure it also preyed on softbodied creatures, many of which were preserved at the famous Burgess Shale locality in western Canada.

I don't know who drew this beautiful picture of Anomalocaris or I would give credit here.

dirty little club

It looks like trilobites played golf. On dirt, since grass hadn't evolved yet.

trilobite with a dinky

spine, several of them, but so small. Field of view only ~1/2 mm wide. Surface would have felt rough.

Tiny trilobite

Three views of same specimen. Trilobite about 1.5 mm long. Agnostus sp. Conasauga Formation, Upper Cambrian, Alabama. Photo by Ann Arnold.