LINDA WERTHEIMER, HOST:
Good morning. I'm Linda Wertheimer. Twitter is going to the dogs. Yesterday, Patch, a Jack Russell terrier, boarded a train near Dublin. When the train staff discovered him, they posted his picture on Twitter. It was re-tweeted more than 500 times. Within a half hour, his owner saw the photo and tweeted: That's my dog. Then she opened a Twitter account for Patch, in case he should go missing again. It's MORNING EDITION. Transcript provided by NPR, Copyright NPR.