海洋岛屿 14

And few islands are more remote than these.

2,000 miles from the nearest continent

Hawaii is the world's most isolated archipelago.

It is so far flung

that less than 500 kinds of animal settled here in 30 million years.

Remarkably

Many of these colonisers were carried to Hawaii on the back of cyclones.

For an animal to be sucked up by storm winds

carried across the ocean and dumped here alive

was a matter of extraordinary luck.

Yet that's what happened to the ancestor of this insect.

It's a kind of fruit fly, but no ordinary one.

Hawaii's fruit flies are the birds of paradise of the insect world.

They attract females with elaborate courtship rituals

and have a sophisticated range of territorial behaviour.

Male hammerhead flies use their heads as battering rams.