Something I didn't know about rats

I think most people (well, people with rodent interests) have heard that rats can't vomit, but I didn't know this:

...rats do still need a strategy to cope with ingested toxins. Rat food avoidance isn't foolproof. Rats do experience nausea and have evolved an alternative to vomiting: pica, the consumption of non-nutritive substances. When rats feel nauseous they eat things like clay, kaolin (a type of clay), dirt and even hardwood bedding (eating clay and dirt is a type of pica called geophagia). Their consumption isn't random, though: rats offered a mixture of pebbles, soil and clay after being given poison prefer to eat the clay (Mitchell 1976).

Rats engage in pica in response to motion-sickness (Mitchell et al. 1977a, b, Morita et al. 1988b), nausea-inducing drugs (Mitchell et al. 1977c, Clark et al. 1997), radiation (Yamamoto et al. 2002b), and after consuming poisons (Mitchell 1976), or emetic drugs (Takeda et al. 1993). The incidence of pica decreases in response to anti-emetics (Takeda et al. 1993) and anti-motion sickness drugs (Morita et al. 1988a). Pica in rats is therefore analogous to vomiting in other species.