I've already expressed my excitement at learning random lists of animals with certain features (ie. inability to endogenously make vitamin C). Here are a couple more.
Animals with relatively large stomachs:
Marsupiala (kangaroos and wombat), Artiodactyla (peccary, hippopotamus, chevrotain, camelids, Pecora and true ruminants), Rodentia (vole, lemming, hamster, muskrat), Sirenia (dugong, manatee), Edentata (sloth), and Primates (Colobus and Semnopithecus monkeys).
Animals with no gallbladder:
Horse, deer, elk, moose, giraffe, camel, elephant, pigeon, dove, lab rat, pocket gopher, whale, porpoise, dophin, llama.
Animals prone to Chediak-Higashi syndrome:
Children, mink, cats, beige mice, killer whales.