Here's another one to ponder: Chickens. Because everyone feeds their chickens grains in the coop, we tend to think of them as herbivores, but our chickens are free range and it is very obvious, if you watch them, that their primary food is bugs and worms ... and chicken eggs that broke (or they broke them), and baby chicks that have no mother to protect them, so they are cannibals, and mice and any other manner of smaller critters... Yup, those chickens are definitely omnivores. And they don't even have the teeth of meat eaters, but those beaks can rip up almost anything a carnivore can.