Nature's oldest love stories: why cicadas shout, and why all the workers are women
Some mornings in April, before you've finished your first cup of tea, the trees are already screaming. Not in distress — in desire. That wall of sound isn't random. It's organised, it's urgent, and it belongs entirely to the males.
The cicada has been doing this for millions of years. Buried underground as a nymph — sometimes for seventeen years — waiting for exactly the right moment. Then it emerges, climbs the nearest tree, and produces one of the loudest sounds of any living insect. The organ responsible is called a tymbal: a ribbed membrane on the abdomen that buckles inward and snaps back dozens of times per second. Stack thousands of them on the same tree, and the air itself seems to vibrate.
It is, in its way, a concert where half the audience is also the jury. Only the males perform. The females listen, perfectly still, choosing.
There's something almost poignant about it — a creature that spent the better part of a decade underground, waiting, only to surface with one job: to be heard. The females don't make a sound. Don't mistake silence for passivity. They are the ones doing the selecting.
Inside The Hive
Move from the treetops into a hive, and the power structure becomes even more interesting.
A honeybee colony of sixty thousand individuals is, almost entirely, female. The workers — foraging, building, nursing, fanning, guarding — are all daughters of a single queen. There are males, called drones, but their role is narrow and their tenure short. They don't build. They don't forage. They exist, more or less, to be ready for one brief aerial moment. After that moment, nature has little further use for them.
What the queen controls is remarkable: she decides the sex of each egg. Add a drop of stored sperm as the egg passes, and it becomes a female worker. Withhold it, and the egg develops anyway — into a male. The males are fatherless. They inherit only their mother's genes, half the chromosomes of their sisters. This system — called haplodiploidy — isn't a glitch. It's the engine of the whole social structure.
The queen doesn't choose one mate and settle. She flies out once, early in her life, and mates with up to thirty drones in a single afternoon — collecting sperm she'll carry and use for the next five years. Think of it less as promiscuity and more as insurance: a deep genetic library, drawn upon slowly, to produce exactly the workers the colony needs.
How The Queen Decides
The mechanism is called haplodiploidy, and it works like this:
- The queen mates once — during a nuptial flight early in her life — with multiple drones.
- She stores millions of sperm in a specialised organ called the spermatheca.
- Each time she lays an egg, she decides: release a drop of sperm (egg becomes female) or withhold it (egg becomes male).
- Female workers are diploid — two sets of chromosomes, one from each parent.
- Male drones are haploid — one set of chromosomes, only from their mother. They have no father.
The Same Story, Underground
Ants tell a nearly identical story. The ant you see carrying a crumb three times her own weight is female. So is the one guarding the entrance. So is every tunnel-digger, every nurse, every scout. The colony is, in effect, an extended family of sisters — all daughters of one founding queen who took her own nuptial flight, stored her sperm, and spent the rest of her decades-long life laying eggs underground.
There's a quiet strangeness to it when you sit with it long enough. We tend to think of societies as things built from competing interests. But the hive and the colony run on a kind of genetic unity that makes selfishness almost structurally impossible. When you work for your sister, you are — in a very real sense — working for your own genes.
Terms Worth Knowing
- Tymbal — the sound-producing membrane on a male cicada's abdomen.
- Haplodiploidy — the sex-determination system in which fertilised eggs become females, unfertilised eggs become males.
- Spermatheca — the queen's sperm-storage organ, holding sperm for years after a single mating event.
- Nuptial flight — the mating flight of virgin queens in bees and ants.
- Eusociality — the highest level of animal social organisation, with cooperative brood care and a division of reproduction between queens and workers.
The next time you step outside into that April wall of sound, or watch an ant line crossing your kitchen floor, it might be worth pausing — not to identify the species, but to notice what you're actually looking at. Ancient solutions to ancient problems. Love, labour, and the quiet question of who gets to choose.
Nature doesn't explain itself. It just keeps working.
