Tomatoes belong in fruit salad, and the cause of every plane crash is gravity.

when humans say "an animal" in the English language, they're referring to "non-human animals". Being called an animal in itself isn't insulting either before you go there. Hardly anyone would be insulted at being called a lion. I think everyone who can read understands exactly the implication being drawn and the dehumanizing being done. Everyone from slave traders, colonialists, nazis,etc.. have used "monkey" to dehumanize people. Same with "dog" , "snake" ,etc.. in different contexts.