While researching ground squirrels native to the Central and Western U.S., squirrel scientist Hilary Srere discovered the mammal hibernates, almost coma-like, with only one or two heartbeats per minute. While that lethargic, one can take advantiage of the little critters. “I did juggle three of them for my niece and nephew when they were younger, because they are just little fluffy balls!” she says. “They don’t wake up, they just don’t.” The Atlantic Cities. Click image for action.