This somewhat randomly popped up on one of my news feeds:
http://www.sciencedaily.com/releases/2015/02/150205095155.htm
"Norwegian lemmings dress loudly and scream even louder to survive"
Hmm, sounds like a real-life version of the proposed screamer skill (http://www.lemmingsforums.net/index.php?topic=2012.msg49334#msg49334)?
As Bruce Banner would say, you wouldn't like them when they're angry. ;P
http://www.youtube.com/watch?v=3-9edqTJBXE