On: Zebras of all stripes repel biting flies at close ...

[SoftTalker]

I wonder why, over the long term, the flies did not adapt to this.

[gcanyon → SoftTalker]

Or the short term -- flies have much shorter generations. That doesn't guarantee faster evolution, but it helps.

[jabl → gcanyon]

Maybe the adaptation would require significantly more advanced visual processing with attendant increase in weight, size, and energy consumption, making it not worth it?

[miohtama → SoftTalker]

Maybe compound eyes have some inherit flaw that makes it harder to process visual signal of stripes.