Ripe bananas glow blue in ultraviolet light.
Like many fruit, unripe bananas are green because they're still full of chlorophyll. In bananas, that chlorophyll breaks down into a UV reactive pigment.
Some birds and insects are tetrachromats, and can see UV light. To them, bananas which are ripe and ready to eat are super obvious, and easy to see from the air.
@InvaderXan Ah, and now we're imagining a ParrotVision kind of thing that's actually bright purple due to the ultraviolet wavelengths.
Sunbeam City is a Libertarian Socialist solarpunk instance. It is ran democratically by a cooperative of like-minded individuals.