Watch Fallon, Seth MacFarlane Sing Yahoo! Answers on 'Tonight Show'

Comedy-crooner supergroup answer ridiculous queries like, "Can a veterinarian tell how many lives a cat has left?"

Jimmy Fallon and Seth MacFarlane formed the "Yahoo! Answers Lounge Singers" on 'The Tonight Show.'

One of Jimmy Fallon's late-night staples is bringing on Tony-winning vocalist Audra McDonald to belt out absurd Yahoo! Answers. But for Tuesday's episode, the host recruited comedy-crooner Seth MacFarlane to form Tonight Show supergroup Yahoo! Answers Lounge Singers, singing answers to real, ridiculous questions submitted by Yahoo! Answers users. 

The duo conjure a hammy lounge atmosphere in the clip, delivering their laid-back Q&A while staring at each other from behind two grand pianos. "Can a veterinarian tell how many lives a cat has left?" Fallon asks, to which MacFarlane responds, "Yes, they can. They need to cut a part of the tail off and count the number of rings left. It's like a tree."

The silly queries continue, interrupted by Fallon's sultry fake piano-playing. "What does 'TGIF' stand for?" the host asks, earning the satisfying answer, "The Goat is Fed." And "Are skeletons real or made up?" brings a tasty response: "Skeletons, contrary to popular belief, are made of marzipan by the finest French confectionary chefs."

Fallon switches gears into some holiday questions, with MacFarlane explaining how Santa knows we're sleeping ("The same way peeping Toms know. The looks in your window. But when Santa does it, it's not weird."), the actual spelling of "Chanukah" ("Chaka Khan") and the best Christmas routine ("The the balls out of the box…wash 'em…dangle 'em from the tree.").