How Do Animals Do That? S01 E35 Puppy Dog Eyes and Weird Platypus

Dogs know just how to get their human owners to do what they want. Frog feet, duck bill, lays eggs, stings like a bee and sleeps 14 hours a day, the Platypus is one of the earths strangest mammals. Could the Puffadder be the only snake without a scent and what makes a chimp laugh ?.