A member of the petra genus, this organism is quite unique. Though the majority of members of the petra genus group together, mater takes it to a level beyond. The organism will form several offspring, and arrange them in a pile. This "mother" organism will feed and rearrange these newly developed organisms over and over until they reach a size suitable enough and roll off to complete the same act. It is not uncommon a "mother" to give too much energy to the new organisms, resulting in an untimely passing. However, these "mother" rocks will have several batches of offspring before rejoining the soil one way or the other.
No other organism has such an obvious, hands-on relationship with another organism.