The Thylacine. circa 1906. Photo taken at Hobart Zoo, Tasmania. Now extinct. The Thylacine (aka Tasmanian Tiger or Tasmanian Wolf) was a carnivorous marsupial. The last one seen was in 1933. It is now extinct.
The extinct Dodo bird. Even though the rareness of the Dodo was reported already in the 17th century, its extinction was not recognised until the 19th century. This was partly because, for religious reasons, extinction was not believed possible until later proved so by Georges Cuvier, and partly because many scientists doubted that the Dodo had ever existed. Like many animals that evolved in isolation from significant predators, the Dodo was entirely fearless of humans.