It's pretty fascinating.
Cats don't usually see bananas (or cucumbers/zuchinni, which will also make them do this) in the wild, so they don't really know what they are. They don't eat them, and most feral cats don't live near them.
The closest thing in their minds to those shapes and colours together is snakes.
And snakes are not to be fucked with, which is why they tend to have these wild escape-type reactions.
Cats don't usually see bananas (or cucumbers/zuchinni, which will also make them do this) in the wild, so they don't really know what they are. They don't eat them, and most feral cats don't live near them.
The closest thing in their minds to those shapes and colours together is snakes.
And snakes are not to be fucked with, which is why they tend to have these wild escape-type reactions.