Porcupines smell like human body odor.

If you were to close your eyes around a bunch of sweaty gymgoers and a prickle of porcupines, you may have trouble discerning which is which. That’s because the pungent smell that emanates from the North American porcupine has been compared to human body odor, though others have also likened it to human urine, barnyard goats, or exotic cheese.

Porcupines produce the offputting fragrance from a patch of skin near their tails called the rosette, containing sebaceous glands that secrete the downright rank aroma. While the musk is present at all times, you normally wouldn’t get close enough to notice it — unless you want a face full of quills. The odor, which is used as a defense mechanism to ward off predators, gets noticeably stronger when porcupines feel threatened. That said, there’s no telling how porcupines would smell if they started lifting weights or running on treadmills.