This skill will allow you to listen at each exit, in an attempt to hear noises. If you detect noises then likely there is a living soul (or more) in that direction. This skill will give wrong information if you fail it.
This essentially allows you to use the Listen command for all the rooms surrounding you, giving the sub-race (such as humanoid, animal, fish…) of all the monsters in the surrounding rooms if you succeed. It can be handy if you either don't get a better detection skill, if you have a better skill but you want to check all surrounding rooms, or in cases like with Enhanced Peer where the better skill does not work in all situations.