You'll have noticed I mention eggs a lot in my posts. There's good reason for this - eggs are important. For the bees, they are as important as honey - during the first half of the year, they are the basic unit of production for the hive - the colony's GDP. Without eggs there would be no workers, and no way to replace a lost queen. And, as I've probably mentioned before, at the peak of the season (right about now, in fact) the queen can lay up to 2,000 eggs a day.
So, what do they look like? Well - like this:
To give you an idea of scale, here's the same egg with a worker bee in the (out-of-focus) foreground:
This particular egg was laid in a queen cell. Interestingly, there is actually no difference between an egg that is laid in a queen cell (and destined to be a queen) and one laid in an ordinary hexagonal cell, and destined to be a (female) worker bee. The differentiating factor is in the feeding. For the first three days, all bee larvae are fed on royal jelly. After three days, workers and drones are then fed on a different substance, which is similar to royal jelly, but - crucially - lacks the protein royalactin.
Queens, however, continue to receive royal jelly until their cells are capped. The royalactin in the royal jelly induces the uptake of epidermal growth factor receptor, which in turn causes changes in cell growth and metabolism as the larva develops - which is why she becomes a queen instead of a worker. It's all controlled by the gene PI3K/Akt, which is a signalling gene - this means it has the ability to switch other genes on or off, depending on the cellular chemistry (increase in epidermal growth factor receptor in the case of queen bee larvae).
Drone (male bee) eggs are different, though. They look the same, but internally they only have one set of chromosomes because they are unfertilised (fertilised eggs have a set of chromosomes from the mother, and also a set from the sperm that fertilised them). This means that, peculiarly, drones have no father...!
A question I inevitably get asked is - do I get stung? Well, unfortunately yes - though not every time I open up a hive. It's just something you get used to, if you decide to become a beekeeper!
I remembered to take a picture of a sting when I was stung recently - here it is:
Stings are quite interesting structures. A sting is actually a modified ovipositor - this is a narrow tube at the end of a female bee's abdomen (wasps have them too), down which the egg travels from the ovary when it is laid. In a worker bee, who doesn't lay eggs, the venom travels down the sting from the venom sac (inside the abdomen). The sting in worker bees is barbed, which is why it gets stuck in your skin when a bee stings you - and gets left behind when the bee flies off (and dies, unfortunately).
The queen bee also has a sting, but very rarely uses it. It's mostly used for killing rival (sister) queens, often when they are still in their cells waiting to emerge (she will nibble a small hole in the side of the cell, and then sting her sister through the hole). Queen bee stings are not barbed, so she can sting multiple times and still live to fight another day.
Because a sting is a modified ovipositor, which is a structure for the female activity of laying eggs, male bees (drones) don't have them. So if a drone ever lands on you, don't panic - he can't sting you!
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