The exhibit under 'Extremely Weird': the platypus.
*facepalm* which is a monotreme, not a mammal.
I thought the egg-laying disqualified it, I forgot there was a distinction between 'placental mammals' and 'mammals with other weird hookups'.
God stepped on the beak of the poor platypus
And that's how he came to have so flat a puss.
Oh, who can imagine what it's like to be stuck
With a rear like a beaver and a front like a duck?
If that's an intelligent design, God must have been nipping at the cooking sherry while He was on the job ;)