You know how rabbit poop is usually seen in the form of little hard pellets? Well, let me tell you something, that's not how it originally looks.
You see, rabbits (and some other animals) practice coprophagia, which is the ingestion of their own feces. For some reason, when they eat, they don't absorb all of the nutrients, so they have to reingest it a second time. Don't believe me? Look it up!
And, keep an eye out for a new video on you tube...two bunnies, one cup.