Tried this on the Critique thread (which doesn't come up on Active Threads) so will try and get a more general view as I got no answer from the "comedy experts"
MODERATOR EDIT: This has been moved into Critique. Please don't double-post.
The post :-
My wife asked me to explain this joke she read in the paper yesterday....................and I couldn't help her. What have I missed ?
"Of all the materials on Earth to choose from, why did God advise Noah to 'go for wood' when building the Ark?"