Buff-tailed bumblebee (Bombus terrestris) by zoo-logic
For just one day a year, millions of ants across the UK take to the air in what is known as the nuptial flight - those in the London area may have noticed that for this region, that day was yesterday. This annual event is the time for winged ‘princesses’ - virgin queens - and male drones, collectively known as alates, to get a taste of the outside world where their sterile female workers roam during the rest of the year. The ants choose their day carefully based on temperature (warmth makes it easier for them to fly), humidity (damp soils are softer to dig new nests) and day length (the ritual always takes place in summer). Amazingly, flights are somehow coordinated between nests in the same region in order to maximise the chances of meeting with ants from other colonies to mate. How this is done is not yet fully known, but it is likely to be through a chemical signal. After emerging, the princesses release pheromones to attract male suitors, and ensure they get the strongest mate by outflying the males so that they must work to keep up. During her nuptial flight a princess will usually mate with several drones, storing the sperm in a ‘sperm pocket’ that will last her a lifetime: after mating, she loses her wings and buries underground, where she will start a new colony and use sperm reserves to fertilise tens of millions of eggs over the course of up to 15 years. The males, on the other hand, have completed their role in mating and die shortly afterwards.
The Society of Biology is studying patterns of flying ant emergence across the UK to determine country-wide levels of synchronisation and is calling on the public for your help - if you have noticed any flying ants in your area submit your sightings here!
Ref: BBC News, 2012. Who What Why: How do flying ants know it’s mating day? [link]
Mccarthy M., 2012. Cleared for take-off: it’s the day of the flying ants. The Independent [link]
Nuptial flight: When Flying Ants Mate in the Skies. AntArk [link]
Garden bumblebee (Bombus hortorum) by zoo-logic
When a honeybee dies it releases a death pheromone, a characteristic odor that signals the survivors to remove it from the hive. This might seem a supreme final act of social responsibility. The corpse is promptly pushed and tugged out of the hive. The death pheromone is oleic acid [a fairly complex molecule, CH3(CH2)7CH=CH(CH2)7COOH, where = stands for a double chemical bond].
What happens if a live bee is dabbed with a drop of oleic acid?
Then, no matter how strapping and vigorous it might be, it is carried “kicking and screaming” out of the hive. Even the Queen bee, if she’s painted with invisible amounts of oleic acid, will be subjected to this indignity.
Do the bees understand the danger of corpses decomposing in the hive? Are they aware of the connection between death and oleic acid? Do they have any idea what death is? Do they think to check the oleic acid signal against other information, such as healty spontaneous movement? The answer to all these questions is, almost certainly, No. In the life of the hive there’s no way that a bee can give off detectable whiff of oleic acid other than by dying. Elaborate contemplative machinery is unnecessary. Their perceptions are adequate for their needs.
Ann Druyan & Carl Sagan, Shadows Of Forgotten Ancestors: Who Are We?, What Thin Partitions