Why do Cowboys yodel?

Being of European background, I associate yodeling with mountains, cows and guys in lederhosen.

I was surprised to find that yodeling was and is a popular activity among cowboys.

How did that come to pass?

Thanks!
Oliver

IIRC, Bitterdrunk Kid provided a pretty definitive answer in this thread:

http://boards.straightdope.com/sdmb/showthread.php?threadid=85818

Since this has been discussed so recently, I’ll close this thread and direct any further comments to the earlier thread, linked to above.

bibliophage
moderator GQ