In Australia, marsupials and placental mammals have evolved to share many similar characteristics. This type of evolution may be referred to as
Adaptive Radiation
Divergent Evolution
Cyclical Evolution
Convergent Evolution
$A$ : Placental wolf and Tasmanian wolf (a marsupial) show convergent evolution.
$R$ : Like marsupials placental mammals in other parts of world also exhibit adaptive radiation in evolving into varieties of such placental mammals each of which appears to be similar to a corresponding marsupial.
Explain the interpretation of Charles Darwin when he observed a variety of small black birds on Galapagos Island ?
Process of evolution of different species in a given geographical area starting from a point and literally radiating to other areas of geography (habitats) is called.
It is not an example of Australian marsupials.