Tuna is not an ordinary 3 year-old Chiweeni dog - he’s a real Internet sensation. He has his own website and Instagram account, has been widely written about online, and is followed by hundreds of thousands of people. What’s Tuna’s secret charm? It’s definitely his unusual appearance – he has an irregular face with a crumpled chin and teeth that stick out. Tuna’s priceless facial expressions, captured by owner Courtney Dasher, are the key to his success.