Did the Linux community ask permissions to use as a Logo an animal that exist?
Did education institutes ask permissions to use animals as animated characters?
I don't know, but some of this animals could feel offended, for being used for non-animal solutions.
Dogs are polices? Cats are Gypsys?
Pigs sniff, and they are not so durty as you think.
Parrots can speak and they are not offensive or defensive.
Birds can sing, without letters indeed.
If I use another human to create a comparative expression, I can have problems with that use case.
Maybe we should process in court those who use animals as logos, since the comparative expression can be offensive.
You look like a Dog. You look like a Cat. You look like a Pig, a Monkey and a Elephant.
Maybe you should think first, about this comparative expressions, since you have a brain.