Dung eaters feed on waste, either of other species or their own. Those that eat their own, such as rabbits and ringtail possums, do it because it's so hard to extract nourishment from their nutrient-poor diet that digesting it a second time is worthwhile. In contrast, pikas eat their own dung to keep their salt levels in balance. Some dung eaters, like the dung beetles, play an important ecosystem role in recycling waste and helping to disperse or germinate seeds in the dung.

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