She did scream, though, when she uncovered the milk: “It’s black!” There was a veil on top of drowned or swimming ants. “It’s all on the surface,” I said. “One can skim them off with a spoon.” But even so we did not enjoy the milk; it seemed to taste of ants.

In the above quote, the narrator's wife exclaims that the Argentine ants have found the milk. The surface of the milk is "black" with dead ants. The text tells us that the ants are ubiquitous, and both the narrator and his wife are seemingly helpless in the face of the hymenopteran onslaught.

What is interesting is that the ants have breached every human sanctuary in the home. The ants don't acknowledge human expectations or institutions (the family). Even the baby has been the target of their exploratory excursions. Despite this, the Argentine ants appear to have left the baby unharmed: the narrator's wife can find no bites on the infant. All things considered, the ants are primarily focused on survival and just as determined to prevail as are the narrator and his wife.

My wife calmed down a little, but I didn’t. I had said I’d seen the entrance to the ants’ nest to console her, but the more I looked, the more new ways I discovered by which the ants came and went. Our new home, although it looked smooth and solid on the surface, was in fact porous and honeycombed with cracks and holes. . . .

Shall we ever be able to get the ants out of the house when over this piece of ground, which had seemed so small yesterday but now appeared enormous in relation to the ants, the insects formed an uninterrupted veil, issuing from what must be thousands of underground nests and feeding on the thick, sticky soil and the low vegetation?

Here, the author reinforces a sense of claustrophobic tension by highlighting the porous texture of the walls. Since the walls themselves are pockmarked with cracks, there is nothing to keep the ants out. Additionally, the ants represent an indomitable army bent upon dominating both natural and man-made landscapes.

More ominously, the ants seem to be prevailing in the classic man versus nature conflict. Even the narrator admits that the ants are like "fog or sand." The insects appear invincible and manage, by their sheer numbers, to neutralize the framework of human ingenuity.

“D’you want some Profosfan? Or Mirminec? Or perhaps Titobrofit? Or Arsopan in powder or liquid form?” And still roaring with laughter he passed his hand over sprinklers with pistons, brushes, sprays, raising clouds of yellow dust, tiny beads of moisture, and a smell which was a mixture of a chemist’s shop and an agricultural depot.

“Have you really anything that does the job?” I asked.

They stopped laughing. “No, nothing,” he replied.

In the story, Signor Reginaudo seems to possess every insecticide known to man. Despite this, he remains helpless in the battle against the Argentine ants. Many readers, however, see his levity as troubling. Is Signore Reginaudo's levity a sign of absurdist leanings on the part of the author? Recall the myth of Sisyphus, condemned to fruitless labor for eternity. Here, Signor Reginaudo uses every insecticide he can get his hands on. Yet, they do nothing to stem the onslaught of ants.

Some experts suggest that Signor Reginaudo's levity is a form of narrative paidia. Here, paidia refers to the Greek practice of describing the physical manifestations of feelings of euphoria. So, the questions begs to be asked: is Signor Reginaudo utilizing a form of gallows humor, laughing because he realizes the absurdity of fighting the ants?

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Image, Eye, and Art in Calvino by Birgitte Grundtvig