[Batesian mimicry.][1]

> Batesian mimicry is a form of mimicry where a harmless species has evolved to imitate the warning signals of a harmful species directed at a predator of them both.

You have probably heard of the coral snake and the milk snake:

> ”Red on yellow kills a fellow. Red on black venom lack”
>
> Due to the many colors of the eastern [milk snake][2] (L. t. triangulum), it can resemble the coral snake, corn snake, fox snake, scarlet snake, and most importantly, the venomous snake genera Agkistrodon and Sistrurus.

Disguise like a well known dangerous group, like the milk snake does, resembling the coral snake, or some fly does showing yellow and black stripes typical of wasps.

Most of those spotting you would prefer to move away rather then checking if you are really a menace or not.


  [1]: https://en.wikipedia.org/wiki/Batesian_mimicry
  [2]: https://en.wikipedia.org/wiki/Milk_snake