opossum

The opossum are at the base an american animal but it is comun in australia and is name "possum" so what is the difference ?

They look like the oposum but why this american animal it is in australia and why is name so ? 

The english botanist have believed at the new species of opossum so they named him "possum".

The possum lived in th tree on jungle of australia they move only in night .Is compare at a big rat ,he have a big hear whith a cute head.

they harmless for the Human.