Deemed the smartest of all dogs by psychology professor Stanley Coren in his book, "The Intelligence of Dogs," the tough little sheepdogs have data to back up the IQ claims. The two smartest dogs on record, with the proven ability to understand up to 340 words, are both border collies. The dogs, brought to the attention of scientists by their proud owners, were the subject of research conducted in their own homes by Juliane Kaminski, a cognitive psychologist at the Max Planck Institute for...