Anyone who has ever owned a dog – been greeted with a wagging tail and barks of delight – would say, of course, their dog loves them.

But science has been more hesitant to attribute emotion to certain animal behavior. Maybe a dog only cares about the food they are about to get? Maybe a dog has been trained to behave in this way? What about dogs who don’t have a friendly human in their life?

Behavioral scientist Clive Wynne was trained to think this way as well. But through his recent research, his thinking has evolved. He says a dog’s ability to love is precisely what makes them a unique species.

Clive Wynne’s new book is “Dog is Love: Why and How Your Dog Loves You.”