Male ants - how does a queen produce drones?

Male carpenter ant (drone) photographed in Clearwater, BC, 2026

Some insects, such as aphids, can reproduce parthenogenically, that is, to make clones of themselves.  Most insects, however, require a male and female to reproduce.  All Hymenoptera (ants, wasps, and bees) are this way.  You probably know that male wasps and ants are rare; most of the brood are female.  However, the queen can choose to produce a male (if only King Henry VIII had such a bride!).

Here's the weird part.  An unfertilized queen mates with a male ant and stores the sperm in an organ called the spermatheca, which stores the genetic material and keeps it viable for a long time.  The length of time can be impressive, with some queens mating only once and keeping the gametes for up to 10 years.  The queen produces an egg and allows a stored sperm to join with it, eventually producing a worker, always a female.  However, if a queen lays an unfertilized egg, it becomes a drone.  That's because the Hymenoptera use a system called haplodiploidy.

Ants don't have sex chromosomes like humans do (X and Y chromosomes).  Instead, a double set of chromosomes (diploid state) always produces a female, and a single set of chromosomes (haploid state) always produces a male.  This system of sexual differentiation is called haplodiploidy.  A fertilized egg from a queen becomes a worker, while an unfertilized egg produces a male.

This begs the question, "How are queen ants produced?"  We know in bees, royal jelly is fed to a larva to produce a queen bee.  The process is similar in ants.  A young larva is fed a high-protein diet which leads it to become larger and to develop flight muscles and wings.  Reproductive organs are also developed.  A single queen is not usually produced, just as a single drone is usually not.  Instead, multiple alates (adult Hymenoptera with the potential to mate) are released at the same time, from multiple colonies, allowing the genes in the local population to mix.

This was the first male ant (drone) I have ever photographed.  How interesting.

Thanks for reading. 

Eric Svendsen     www.ericspix.com