Treebeard is said to be ; 

> 'The oldest Ent **alive**'

This suggests that Treebeard might not have been the first Ent. If he was the first ent,  then he would be Three Ages old! This sounds rather unlikely unless Ents are immortal like elves  (see my other question) .

So , is Treebeard the first Ent  ? If not who is the first Ent  ?