They are clearly familiar with meat-based animals:

> “That’s ridiculous. How can meat make a machine? You’re asking me to believe in sentient meat.”

> “I’m not asking you, I’m telling you. These creatures are the only sentient race in that sector and they’re made out of meat.”

And indeed sentient species that are partly made of meat:

> “Maybe they’re like the orfolei. You know, a carbon-based intelligence that goes through a meat stage.”

> “Spare me. Okay, maybe they’re only part meat. You know, like the weddilei. A meat head with an electron plasma brain inside.”