My suspicion is that dogs and cats are reincarnated humans ascending a spiritual scale of evolution. They are angelical creatures, closer to God. Animals are inherently far more moral than people, you see. Animals do not know how to lie.
You see improbable friendships between incompatible animals all the time. I think that such creatures knew one another in an earlier incarnation, and across time, beyond corporeal forms, they remember their friends and their loved ones from another life.
Horses that have a doggie friend. Cats with squirrels, even cats with birds. My wife sent me a video of a dog with a turtle friend yesterday. Dogs and cats in America in particular coexist in our hearts and in our homes.
I have known goats that were a higher order of being than humans, and I fear that our cattle policies, the way that we treat pigs, jeopardizes the very soul of humanity.
The Nazi holocaust is the only event that compares to the way that we treat the animal kingdom, and it is a wonder that the animals do not rebel and kill us all. Sometimes they do. Elephants in Thailand rampage all the time.
If you have ever met an elephant, all that you need do is look into its eyes. You will inescapably sense a soul looking back at you.