Out with the old; In with the new! — Twig Ants

Elongate twig ants (Pseudomyrmex gracilis) carrying food to the nest.

More pictures from the Pseudomyrmex colony that nested in my window lining last spring.  The workers above posed nicely on the window glass as they all tugged on a bit of food.  Normally the workers of  Pseudomyrmex colonies tend to forage independently, relying on their speed, size, and potent sting to bring down prey and haul it back to the nest alone.  However, in this case, the haul in question apparently attracted the attention of some other workers.  People tend to think of ant colonies as perfectly synchronized machines, operating in perfect unity.  However, anyone who has actually watched a group of ants attempt to maneuver a large prey item down a small nest entrance will have noticed that it’s more like a game of tug-of-war, with hopefully most of the pieces deciding to pull in the appropriate direction.  The same sort of ‘rule-by-majority’ principle applies to any number of colony processes, such as selection of a nest site.  I have personally watched a group of acrobat ant workers purposefully hauling larvae to a new nest location, while a second group of workers diligently hauls them right back, passing each other on the way.  They’ll also drag the queen along if she doesn’t cooperate.

A twig ant worker (Pseudomyrmex) removing trash from windowsill nest.