btc1951,

Getting the lingo right is half the battle. What you are calling a World Ancestry Tree is an Ancestry World Tree, or AWT. You'll see a good deal of arcronyms on the boards. Study up!

This is a link to another thread that discusses the trees, hang in to the bitter end, you should get to the answer to your question.

http://boards.ancestry.com/topics.rw.worldconnect/14135/mb.a...