Division of Labour in Ghost ant colonies

 

Ant colonies have a high degree of labor division. The youngest ants rarely leave the nest, as their primary job is brood care. The oldest workers perform the most dangerous jobs, which involve leaving the colony to forage for food and water and protect the nest against enemies. Here, ghost ants (Tapinoma melanocephalum) are seen collecting water for their nestmates. They store the water in their gasters, which expand as they carry more liquid. From the size of the gasters, we can see how long they have been at the watersource.

Photo: Marco Mancini

A new ant genus in Iceland

These ants have been found recently inside an apartment in Reykjavík. They belong to the hyperdiverse genus Pheidole, which comprises more than 1200 described species and is characterized by two castes of workers: major and minor. It is hard to say at this stage at which species these ants belong, and we will further investigate, but we believe this to be a significant discovery for our research.

Ant queen laying an egg

Ant workers perform several different tasks, including caring for eggs, larvae and the queen; cleaning and patrolling the nest; foraging; defending against invaders and parasites. Typically, younger workers remain in the nest to take care of eggs and larvae while older ones perform more risky duties, such as foraging outside and defending the colony. In this footage, we can observe a young worker helping the queen to lay an egg, which will be moved to the nearest egg pile.

Roger’s ant worker

A rather uncommon sight – Roger’s ant (Hypoponera punctatissima) workers are strongly cryptic and rarely collected: they spend all their life wandering underground in search of food. Thanks to a very fortunate event, we succeeded in capturing the exact moment in which a worker (the one on the left) met a queen (in darker brown) for a quick exchange of information.

Ghost ant feast.

Ghost ant (Tapinoma melanocephalum) workers mostly need carbohydrates as a source of energy and they love to consume honeydew excreted by mealybugs and aphids. In an artificial nest, a colony can be almost exclusively fed with maple syrup and sucrose solution droplets. Nevertheless, a certain amount of protein is needed since larvae and reproductive adults rely heavily on proteins for growth and egg production respectively. Our big ghost ant colony is avidly feeding on this piece of king mealworm (Zophobas morio) since the queens just produced a large number of eggs and tens of larvae are already developing.