Feisty Fruit Flies

Antlered fruit fly from Papua New Guinea.

On the continental island of New Guinea, there has evolved a quite extraordinary version of fruit flies that over millions of years have colonised the world.

A fruit fly with antlers. Only the males have them and the size of these strange extensions of the insect's cuticle has a significant effect on their mating success. Just like a rutting moose or deer this antlered fruit fly must fight with other males for the privilege of mating.

It's a pushing contest to decide ownership of a select spot on this fallen mahogany tree. A battle royal over a site where there is a fungus in the wood that will be ideal food for their larvae. One of these males has claimed such a fungus patch, and is determined to win the right to mate here.

Aggression between pair of male antlered fruit flies, Papua New Guinea.

Even when he's proved his strength and is exercising his mating privilege, he must still fight to ensure it's the eggs he's fertilised that are laid in the fungus.

The male antlered flies of New Guinea are in control of a rare resource here –the fungus– and must defend it against others. Evolution has elaborated magnificently on the equipment they possess to do so.

They are closely related to the picture winged flies of Hawaii that I wrote about last August. And as usual these still frames have been captured from moving images held in the NHNZ Images collections. If, while I have your attention I can tell you about our subscription based newsletter, you can sign up on our website, and past articles can be read on our news blog.