How come none of the main characters in Doonesbury ever have pets? Can GT draw animals?
No, he can’t, but that’s not the reason. Pets aren’t part of the franchise. Once you introduce pets, then you have to resist the overwhelming temptation to anthropomorphize, cutely. While this actually works in Peanuts, it probably wouldn’t in Doonesbury. The closest the strip ever came to pets was Zonker’s plants, but given whom they were conversing with, they were probably better described as figments than pets.