Fossil Friday

This week on Fossil Friday we have a specimen that totally stumped me. Take a look!

What is this thing? This thing confused me. When the intern took it out of its case, I couldn’t even tell what sort of Giant Sloth artifact it might be. With all those swirls and whorls and spikes, it had to be organic. But what on earth was it? I asked the intern what this thing was. While she made a game attempt at exuding confidence, I could tell she didn’t know, either. The curator came by and picked it up: she knew right away what it was. So it is possible! Can you do it? The first person to identify this mysterious fossil wins bragging rights for the week!