Action Stations

I walked past the base of the garden sunshade and realised I have not moved it for a while, which risks killing the grass below it. Moving it revealed a scurrying mass below, along with very obvious creamy eggs. My first reaction was slight apprehension: "red ants!!". I've had a few run ins with them over the years, but the angry red swelling on my knees, from their stings, have mostly disappeared now

But on second inspection, I don't think that's what these are. I believe they are Yellow Meadow Ants which, as the Wildlife Trusts put it, rather unkindly, "appears in our gardens if the grass is not cut too often"

Honeybees and these ants have a lot in common - both hymenoptera, both social insects, with castes of male/queen/worker - but there are very big differences. Queen ants of this species can live for 20 years (bees seldom more than three or four). The ant colony does not construct combs, these eggs are just in a pile in a chamber within the nest that I have exposed. The adults rarely leave the nest and live and feed underground. 

This is the species that 'farms' aphids - breeding them within the colony and 'milking' them for honeydew, then sometimes eating the aphids themselves. They are also the ones that have a symbiotic relationship with the Chalkhill Blue butterfly - they help protect its larvae from predators and, in return, receive sugary exudate from the caterpillar. Larvae and pupae also reportedly 'sing' to the ants; I don't know what tune

I was struck by how rapidly the colony organised itself to move the exposed eggs. This must be a very irregular and infrequent necessity but, within seconds, many individuals were picking up one egg each and carrying it underground - all to an agreed single location, I wonder? I guess the behaviour has evolved to protect the colony from risk from any passing goldfish