Do wasps let off an odor or a sound when in danger...?

Question

so that other wasps come to their rescue

because i accidentally just squished a wasp and now i seem to have a few flying around as if the wasp let off some kind of signal?

WASP EXPERTS I NEED YOU.

hahaha

Answer 1

This because of the same reason skunks let off odor, or any other animals does anything, it is the protect themselves. They are trying to scare away a predator.  

Answer 2

Yes.  I've heard they let off some kind of a smell.  So if you squish one make sure you get the heck out of there.