Scientists found the DNA sequence of the duck-billed playtypus and it is as strange as the animal looks. The DNA sequence shows that the duck-billed platypus is a mix of mammal, reptile and bird. The platypus is a monotreme, from a group of mammals that diverged from the marsupials and placental mammals about 166 million years ago. What an amazing creature: it takes us back in time when mammals used to lay eggs but feed their young with milk. It is great to know that we have a live evidence that links mammals, like us, to the rest of the reptiles and birds. (
Source)