Where do poop and pee go on airplanes?

Dogs come in so many different sizes, from the tiniest teacup terrier to the giant Great Dane. How did we get such a delightful assortment of these furry best buddies? We asked Brains On producer and archaeologist Anna Goldfield to help us find the answer. Got a question that’s been hounding you? Send it to us at BrainsOn.org/contact, and we’ll make sure to bark up the right tree! See omnystudio.com/listener for privacy information.