英语听力：自然百科 虫虫兄弟—8（在线收听）

 It's the ultimate high fiber diet. These creatures can even eat wool. They do have some saving graces. Just as dust mites clean up our dead skin, carpet beetles mop up the hair we shed, as well as any dead insects they find. But it's curtains for the cardigans and the carpet. Meanwhile an armor plated part-time cannibal is cruising the corridors looking for a damp patch. No more than 20 millimeters long, the wood louse is a miniature garbage dispose unit. They eat rotten plants, mold, their own feces, and if food's short, other wood lice. They shed their scaly armor around six times a year, but being caught naked can be a dangerous business. Wood lice would eat their own shell, their neighbor's shell, or their whole neighbor if they catch one *. They breathe through their gills on their underbellies, which they must keep moist to absorb oxygen from the air. And they can take in liquid from either end, through the mouth or tubes near the rectum, it doesn't matter, as long as they are the right way are. What goes in as liquid doesn't come out that way. What most would pass as urine, wood lice excrete as a gas. And these occasional cannibals could be handy in the first aid box. In the past they would prescribed as an indigestion treatment, maybe because of the high calcium content of their shells, hence they're nicknamed pill bugs.