The Strange Symbiosis Between Sloths and Moths

Once a week, three-toed sloths slowly descend from the leafy forest canopy to poop on the ground. Why do these sluggish mammals go on such a long and potentially dangerous journey instead of just letting it fly from the treetops? Scientists now believe the answer has to do with the odd, symbiotic relationship between… »1/23/14 11:00am1/23/14 11:00am