Paussid beetles

Paussid beetles are beetles that live inside ant nests and are never attacked there. Ants cannot smell them as anything at all, so a beetle walks through a colony like a blank space. Bianca studies the species, and the armour and the gas she builds from it are what stop the ant column marching on Great Nest.

Description

Paussids are the size of ants, twenty centimetres at most, and dark red. Their most noticeable feature is the antennae, which spread into a disc of fine fronds like a circular fan. The carapace is ridged, with plates that can be cracked and twisted apart.

Life in the ant nest

They have lived inside ant nests for millions of years, using several means to make their hosts accept them. They eat the ants’ larvae. The ants feed them and otherwise provide for them, and leave them unmolested. To collect some, Bianca’s assistants go down into the colony beneath Great Nest, at some risk to themselves.

Each beetle has a suite of chemicals for the ants around it. The ants are blind and live in a world built on smell and touch, so a beetle can build an illusion for them and steer their hallucinations until suborned units of the colony do its bidding. A colony’s chemical codes change constantly, and the beetles trade chemicals with one another to pass on the most efficient keys for unlocking and rewriting the ants’ behaviour.

Of the species that live off ant nests, the Paussids survive best. The nanovirus works with them here. They are not as intelligent as Portia, though they have a certain cunning, the ability to work together, and a pheromonal toolkit they use with insight.

The master scent

One scent never changes, and it is the secret of the species. It asks nothing of the ants. It tells the colony that nothing is here. A beetle using it is not an enemy, not an ant, not a piece of earth, but a blank the colony skips over. Even an ant whose antennae run over the ridged carapace registers nothing.

The scent is a refinement of their ancestral smell. It persists for a short time after death, which is what makes them worth killing in the last hours before an attack.

Bianca’s weapon

Bianca cannot decode the beetles’ changing chemical language. She can find and copy the master scent, and she has become fascinated by it.

In chapter 3.6 she shows Portia a pen of Paussids in her laboratory inside an ant mound and explains what they are for. They will give her warriors a way into the colony marching against Great Nest.

The plan takes the beetles’ bodies as well as their smell. Bianca’s people drive the collected beetles to the muster, which goes badly because the beetles do not herd and several of them escape, then kill them and peel off the shells. Artisans fit the pieces to Portia and her fellows as chitin mail, cracking and twisting each plate with fangs and the strength of their legs and tying it on with webbing. The armour is heavy, it blocks their vision and it makes jumping impossible.

Bianca also brews the scent into a chemical and seals it in globules of webbing, one for each warrior. Portia’s force climbs into the living fortress of the ant column, and the packages burst. The gas saturates the column with the smell of absence. The ants lose the structure that tells them what to do and what to tell each other to do. Bianca’s tame workers then give them a new one.

Later history

The Paussid strategy is used against colony after colony until the ants are pushed back to their original territory. Great Nest’s scholars still use a Paussid as the yardstick for small intelligence, and judge the captive giant brought down from the sky no brighter, perhaps less.

By Fabian’s time the weapon has stopped working. Most ants are conditioned to resist the master scent, partly because of rivalry between spider cities and partly because the beetles keep hacking the colonies for their own purposes, which leaves them a persistent ghost in the machinery. Fabian works out how to use them as carriers instead, and lines up a host of them to spread his instructions across the width of his army. In his reckoning they understand the bargain and buy their survival with usefulness.

Unanswered questions

• Whether Paussids can think. Portia has no idea, and finds their actions more complex than those of simple animals.
• How the beetles persuade the ants to feed them, since their chemical language is too complex for Bianca to decode.
• Whether any of the beetles that escaped on the road to the muster got clear.