Life Cycle of the Ant

Generally, ant brood go through 4 stages as they develop

Ant eggs are tiny at approximately 0.5 mm in diameter and weighing about 0.0005g. They are kidney shaped and have a smooth sticky surface which enables them to bond together in a mass assisting adult ants to move them about more quickly, such as in emergencies for example; it is easier and quicker to carry many eggs in one go rather than having to pick each individual egg up. Inside your ant farm you may see this as a cluster of tiny white dots.

After about 7 to 14 days of cell division the larvae will emerge from the eggs looking very much like tiny maggots. As they grow, they shed their skin, usually about 3 times in all, increasing in size with each moult from 1 mm to 4 mm. With each successive moult they become hairier, with some of the hairs being hooked to enable, like the eggs, numbers of larvae to hook together for easier carrying. However, at the last moult the larvae are usually too heavy to hook together and are carried singularly. There are some slight differences in the appearance of the larvae of various ant species, for example some are hairier than others. The larvae have no legs, but they are capable of some very small movements such as bending their head toward a food source and, in some species, they can move along very slowly if necessary. When they feed, they suck up the juices of solid foods brought to them by the adult worker ants, or they can receive regurgitated food from them. Larvae have large digestive glands with reservoirs that run the full length of their body opening at the mouth.

After about another 24 to 27 days, once the larvae have gone through all of the skin moults, they experience one final stage, the pupae. Pupae look like white waxy ants that lay with their legs and antennae folded up against their bodies. Some species, such as Lasius niger, do not have a pupa stage but the larvae will spin themselves a cocoon in which it will metamorphosis into the adult ant. To be able to spin a cocoon the larvae must be against a solid object. This could be the ground, the wall of a chamber or, in some cases, the larvae will have soil particles placed on it by the to assist them in the spinning of the cocoon. Perhaps the soil granules act as an irritant causing the larvae to spin its cocoon. Sometimes a larva can be encouraged to spin its cocoon by the worker ant gently pressing its own body against it.

The larvae will eject all its gut contents out and this appears as a small black dot at one end of the cocoon. I have seen my Lasius niger ants with ‘naked’ pupae rather than the usual cocoons in them, and I assume this has happened because the larvae, for whatever reason has not had soil granules placed on it nor has it been surrounded by a hard surface other than the ground it is laying on.

Adult Ant
After, approximately, a further 13 to 28 days (about a total of 8 to 12 weeks from egg to adult ant), and again this varies according to species and ambient temperatures, the adult ant emerges looking very pale and soft. A newly born Lasius niger ant is almost white at first but after a few hours it will darken to black and its exoskeleton will harden.

The particular job that each worker does within the colony depends on its age. New ants tend the queen and brood within the security of the depths of the nest. As the ant gets older so it will change jobs which take it nearer the surface of the ground until, nearer the end of its life, the ant will leave the safety of the nest and forage outside. This is the most economical way of sharing out the chores among the ants. 

One difference between ants and humans is that while humans send their young men off to war, ants send their old ladies.

– E.O Wilson (paraphrased)

Whether it is a worker, soldier (not seen in native UK species), male or queen that develops from a particular larva depends on various factors:

Worker: Normal development and food intake as a larva.

Soldier: Increased foot intake as a larva.

Male: Unfertilised eggs.

Queens: Appears to be food intake related – fed lots more food as a larva, than a worker larva receives.

Ant eggs are tiny; about 0.5mm in size, and approximately 0.0005g in weight.  They are kidney-shaped and stick together making their transport much easier.

(Image: Alex Wild)

After about 7-14 days, the larvae will emerge from the eggs, looking like tiny white maggots.  These ever-hungry larvae will remain in this stage for about 4-6 weeks, shedding their skin a number of times.

(Image: Alex Wild)

For some species of ant, such as Myrmica, the next stage of brood development is the “naked” pupae.  These wax-like objects look like ants folded up. This stage can take 2-4 weeks.

(Image: Alex Wild)

Other species of ant, such as Lasius, enclose their pupae in a papery-like cocoon.  These cocoons are created by the larvae themselves. This stage can take about 4 weeks.

(Image: Cynthia Bingham Keiser)

After approximately 8-10 weeks from the time the egg was laid, the adult ant emerges as either a worker, soldier, winged male or winged female.

(image: Reuters)