Humorous fiction, man adopted by african tribe looking for birth father in US.

I think I read the book maybe 8-10 years ago. All I remember is it was quite humorous and involved a somewhat bumbly man who somehow ended up being raised by a tribe in Africa and who is back in the US looking for his wealthy (I think) white birth father. There's a girlfriend involved, and at some point the birth father ends up going to visit the guy's African family. There's a scene where either the guy or his American father ends up stuck in a tree in the African desert with a lion or hyena (or some dangerous critter) below. I vaguely remember some kind of challenge/quest the protagonist had to go through to either find or be recognized by his birth father.
I wish I remembered more! It was a unique and enjoyable story.