Crazy trivia alert! Canada is home to a venomous mammal. (Don’t worry. It’s small.) The short-tailed shrew is mouse-sized, with minute eyes and ears concealed by a thick coat of slate-grey fur. It usually preys on slugs, worms, and larvae, but, thanks to the venom glands at the base of the teeth in its lower jaw, this tiny predator can bite and paralyze reptiles, mice, or even baby hares. To a much larger animal—say, a person—a bite would be painful, but not paralyzing or deadly.
In winter, shrews use their venom to keep their food alive but immobile. They drag their incapacitated victims back to the nest and stockpile them, in case food sources run low later. The prey lives in this undead-like state—sometimes for days—until the shrew is ready to eat it.
Since they spend a lot of time in underground tunnels or burrowing through leaf litter or snow, shrews have no use for good eyesight (though they can probably at least detect light). Similar to bats and whales, short-tailed shrews use a form of echolocation. They send out ultrasonic ‘clicks’ and listen as the sounds bounce of walls, objects, or whatever unfortunate critters the shrews are hunting.