Got into the gene pool while the lifeguard wasn't watching.
A room-temperature IQ.
A photographic memory, but the lens cover is glued on.
A prime candidate for natural deselection.
Bright as Alaska in December.
During evolution, his/her ancestors were in the control group.
Fell out of the family tree.
Gates are down, the lights are flashing, but the train isn't coming.
He's so dense, light bends around him.
If brains were taxed, he'd get a rebate.
If you give him/her a penny for his thoughts, you get change back.
If you stand close enough to him/her, you can hear the ocean.
One neuron short of a synapse.
Some drink from the fountain of knowledge, but he just gargled.
Wheel is turning, but the hamster is dead.
