A new study has shown that sheep can recognize human faces in photos, and can even recognize their owner because that’s who the sheep are personally familiar with on a day-to-day basis.

But despite research like this, the internal lives of animals are relatively shrouded in mystery. The fields of animal behavior and animal cognition try to combat this by having animals perform certain tests to try and quantify levels of animal logic, reason, and emotion.

For example, corvids -- the bird family that includes ravens and crows-- can use tools both in nature and in urban environments. Some demonstrate complex problem-solving at at least the level of a five-year old. Some even play. Just for the sheer pleasure of it!

All sorts of animals are now being subjected to intelligence tests of different kinds: raccoons, bats, bears, bees, you name it. Can we even classify all the different pathways of communication in our fellow earthlings, or do some of them exist outside our realm of comprehension? Do they have individual consciousness, or even a collective hive mind? We don’t know!