I thought this was already known? What did this study add?
> The team found that tabanid horseflies are attracted to large dark objects in their environment but less to dark broken patterns. All-gray coats were associated with by far the most landings, followed by coats with large black triangles placed in different positions, then small checkerboard patterns in no particular order. In another experiment, they found contrasting stripes attracted few flies whereas more homogeneous stripes were more attractive.
The paragraph before this quoted paragraph seems to imply this study addresses the why, but for the life of me, I can't understand how this paragraph answers why.
Here's the end of the actual study, which sums up the "why" decently.
>Our working hypothesis now is that horseflies are attracted to equid hosts owing to a combination of odour at a distance, then size of the animal contrasted against the sky or vegetation at a middle distance. But at close range, where they can no longer see the body's outline, flies make a visual switch to local features. If these are small dark objects contrasted against a light or white background, the horsefly no longer recognizes this as a host target and veers away. The contrast of stripes and their relatively small size are therefore the key elements of how stripes operate to thwart fly landings.
Maybe they suffer from the barber pole problem. Since there is only an edge, and no corners, the flies cannot localise themselves when they are too close. Without corners, they wont be able to visually tell whether or not they get closer to the target, not if they move along the edge. If the stripes are non-homogeneous. They wont be able to tell neither how far they moved across them either.
Here [1] is a BBC article from 2019 that refers to a 2014 study where they hung zebra-print coats on horses to observe the effect of flies landing on them.
> The team found that tabanid horseflies are attracted to large dark objects in their environment but less to dark broken patterns. All-gray coats were associated with by far the most landings, followed by coats with large black triangles placed in different positions, then small checkerboard patterns in no particular order. In another experiment, they found contrasting stripes attracted few flies whereas more homogeneous stripes were more attractive.
The paragraph before this quoted paragraph seems to imply this study addresses the why, but for the life of me, I can't understand how this paragraph answers why.