As the dingo spread, a fierce competition began. At the time in Papua New Guinea and Australia an animal existed that few know about. The thylacine or Tasmanian tiger roamed the country. It competed with the dingo for food and land. The dingo brought diseases the thylacine had no defense for. The dingo, thylacine and devil lived together for about 500 year and in the end, the dingo won. The thylacine and Tasmanian devil became extinct from Australia and Papua New Guinea. The only place the thylacine and devil existed was Tasmania where dingos never lived in the wild. The thylacine soon became extinct from Tasmania.

White man is another reason for the thylacine decline. Europeans came to Tasmania and brought along their sheep. The Europeans believed the Thylacine killed their sheep and began placing bounties on the thylacine's heads. The government paid one pound for each thylacine hide that was brought in. Around 2,000 thylacines were killed and the survivors suffered from a lack of food and hunting grounds . In 1936, only one thylacine was left in the world and it lived at the Hobart Zoo in Tasmania. The government did not declare the thylacine a protected species until that year and only a few months later, on September 7th, 1936, the last thylacine died because of the negligence of a the keeper.