Brine Marsupials are one of the four known species from the planet Sorenia to have survived its collision with an asteroid, along with Brine Monkeys, Brine Apes and Brine Aardvarks. As all water evaporated from the planet's ecosystem, these lifeforms adapted by encapsulating themselves in cyst-like eggs that hatch when immersed in water. A company called Cereno Products Inc. eventually found out about this and begun mining these eggs to market them as "Space Marsupials". They are provided with the famous "You bought it, you own it" guarantee.