What is the history of marsupials and why do they only live in Australia?

Actually there are marsupials in north and south America( opossums and some types of rats ), but the majority of varieties are in Australia, and New Guinea. Like in the Galapagos islands their evolution did not follow the rest of the larger land masses into a placental type birth because of the isolation of the island and continent They were once widespread over the earth, but were displaced in most regions as the more successful placental mammals evolved. The Australian region, which has been isolated from contact with other regions since the Cretaceous Period answers.com/topic/cretaceous had almost no native placental mammals, and the marsupials were able to continue their evolution there without competition.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.