I always thought Shark >= Dolphin.
Don't forget the Phytoplankton.
Sharks are afraid of Dolphins. Not sure why, maybe because Dolphins are smarter or because they cooperate and fight together. 0.1 XMR is smallest fish on earth , so for lower ranges we will need some other sea creatures, so for satoshi ranges might be a plankton.
Wait a minute, is The Nar-Whale a pocket whale?
I love Narwhals and yes pocked whale was a silly idea.