Ouroboros Spine Oh, in time you'll see

Mordecai described a shell and a varying body size and as Sialuk tried to reconstruct the turtle in her mind, she returned several times to thoughts of a crab. It sounded quite similar—it had a hard back, could be small or enormous, was fun to play with—but it must be different. It had a different name. Surely if it had a different name then its essence, its anirniit, must be fundamentally different. That was how things were where Sialuk came from, so she assumed it was universal.

"Can you eat it?" asked Sialuk, taken with his sudden idea of finding a turtle. Sialuk's primary plan coming out here was to hunt, but if turtles were as edible as crabs, then they'd be working and playing simultaneously. "We could cache it if we find one," she suggested slyly, assuming they weren't poisonous, "no one has to know if we shake it up a bit in the process."