After a thorough investigation of the sink pipes, cupboards, cracks in the moulding, and the relevant Wikipedia articles, I have deduced the hierarchy of the roaches.
Excepting the waterbugs–which live in the pipes and are harmless–the roaches belong to a single species, periplaneta americana, that varies enormously in size. The smallest are invisible to the naked eye. They would constitute a fine film over every kitchen surface were their tiny legs less susceptible to fatigue. But weak as they are, they are rarely found far from their nest. Their elders feed them until their mandibles harden enough for the species’ ritualized cannibalism.
As a rule, roaches eat only their smaller cousins, then metabolize the consumed chitin to enlarge their exoskeletons. As they grow, they gain the strength to venture further from the nest. The smallest of the roaches that I find crawling in the sink has likely eaten its way through many younger generations.
The larger kitchen roaches specialize in collecting loose debris and bringing it back to the nest for the young. This caste dominates our household experience of these insects and indirectly sustains the entire roach population. It is nevertheless ostracized for escaping the cycle of cannibalism and growth The majority of the roaches lives much deeper in the walls, across the burning pipes, through the holes in the foundations, and even in the sewers and bedrock beneath.
An increasingly mature, large, and immobile class abides in each tier of habitat. Nutrients collected from our kitchen counter is passed down the echelons cannibalistically; engagement with the world outside the nest gradually vanishes with age and descent. (I have seen a roach that was six inches long sucking on a hamburger wrapper in a a subway tunnel once, but this is exceedingly rare.) I surmise that to feed the more cthonic generations, the younger and swifter willfully sacrifice themselves to be devoured. And so the species invests its surplus into its own greatest: its fattest and most buried.
Following the logic of their social structure to its limit, we conclude that our hemisphere rests on the stomach of one gargantuan cockroach, wriggling in a sea of its own filth, into whose mouth crawl six-legged leviathans as old as the race itself.
