All animals with smaller brains don't live rationality, they live on instinct. Humans and very few monkey species can think rationality and learn, but most animals just mimic behaviors. Think about dogs, they don't know what your saying, they don't know exactly what is going on, but they can be trained to come, sit, bark, roll over, etc all because you taught them to do it. Once learned, they are queued by a word (just a sound to them) to repeat the actions.
Other then what you teach them, theres no real rational thinking of dogs. They roll in there own waste (it smells good to them), they can bite people who arn't threats (some dogs cant tell, after all most are bred from wolves), and they rip apart clothing/shes just because it has the sent of there owners.
Nothing with brains smaller then ours and most monkeys can rationally think about anything, its instinct.