Why are banksias unique/endemic to australia?

Question

i live in australia myself, but i dunno how to answer this question??? help please?

Answer 1

Banksia species are adapted to poor soil ( laterite or silica sand ) and  cool ( 39–86 °F ) and wet ( around 800 millimeters rainfall ) climate. These conditions are to find in some regions of Australia and dispersal to other countries was hindered by distance.

The exception is B. dentata (Tropical Banksia), which occurs throughout northern Australia, and on islands to the north including New Guinea and the Aru Islands.

For more details:

http://en.wikipedia.org/wiki/Banksia

http://en.wikipedia.org/wiki/Banksia_bro...

http://www.sciencedirect.com/science?_ob...

Answer 2

Also keep in mind that Australia has been a physically separate land mass for a very very long time - not much way for banksia seeds to travel elsewhere until man came along.

Answer 3

Probably because they rely on the other Australian flora such as eucalypts to create the environment for fire. From what I can recall, banksias rely on fire to open their pods and possibly to scarify their seeds(cause to germinate)