SpongeBob Squarepants Easter Egg - The Foghorn

In all the episodes, Spongebob's alarm clock sounds like and is confirmed to be a fog horn

In SB B.C. there are huge dinosaur looking creatures that make that same deep call. These creatures look similar to the way the Leviathan was described in Ray Bradburry's book the Foghorn.

The singl creature in the book was a huge creature from the age of the dinosaurs that had survived deep under water. it came to the surface and was attracted to the foghorn becaus it sounded like the call of its species.

Apparently it was alive during Spongebob B.C.