One day as Tarzan was swinging from tree to tree, he happened to look down at the jungle floor. There he spotted Jane and to his horror he saw a viscous leopard creeping up on her. Tarzan yelled down to warn her and told her he was  coming to rescue her.

He grabbed a vine and swung down towards her yelling “Jane, grab the vine, grab the vine.” When he got close to her she reached up and Tarzan yelled “Jane, grab the vine, grab the vine. No Jane, no….no …..the vine, the vine.”
“Ahh, ahaba ah…ah, ahaba ah…………”

And now you know the origin of Tarzan’s famous yell.