I just watched a video that had a doorbell ringing. As soon as that played, Murphy jumped up, ran into my office and barked. OK, great. He knows what a doorbell is. But I don't have a doorbell. Never have. Where is he getting this from? He's always been a kennel dog or an outside dog before I got him.
Lagniappe was the same way. He'd go nutty when he heard doorbells on TV, too. And again, as long as I had him, I never lived in a house or apartment that had a doorbell.
But the strangest one? My first German Shepherd, Oliver. If he heard another German Shepherd bark on the TV, he'd run into the room from wherever he was and sit right in front of the set, staring at the Shepherd on the screen. (Usually old episodes of "Cops".) If it was any other dog, he wouldn't even stir but if it was a Shepherd I'd usually wind up having to watch the rest of the show between his big pointy ears as he'd be parked a foot from the screen, watching until he was sure that dog was gone.
Oh--and Murphy is alert to engine and vehicle types, too. Not only does he alert to the UPS truck whenever it comes here, but when he was at my mother's over the holiday, he sounded off when an identical Big Brown Truck slowed down in front of her place as well. No other vehicle gets him going, but a braking UPS truck? It's on like Donkey Kong even before the truck is in view.
Oh, and my nephew, The Spud, still can't figure out how come he can never win at Hide and Seek with any of my Shepherds that he's ever played with. They've always found him in seconds no matter how well he's hidden, when they've bothered to actually look for him, that is.
People who think that dogs are dumb really need to watch a Shepherd in action for a bit.