H. Pettijohn on Nostr: As far as I know, once they settled down on the bottom of the ocean, they stayed ...

As far as I know, once they settled down on the bottom of the ocean, they stayed there! :^) In some areas, LOTS of these fellas are found all together, and if I remember correctly, it's theorized they would have formed reefs, much like corals today. These Platyceramus reefs likely served as the base for whole ecosystems, with critters living on, around, and even inside of them.