I got into Florence this afternoon, after ~20 hours of travel – bleagh! I will try catch up on the rest of my time in the US soon, but for now here’s some fun science:
(Sorry about the ad at the start.)
One of the talks I happened across at the conference was about a sort of model for ant rafts. Like any good physics model, it was heavily simplified: a pile of staples being shaken. The idea was to look at how the aspect ratio of the staples (ie: how wide their base is relative to their arms) affects how well a pile of them holds up to the shaking. It turns out there’s an optimal arm-to-base ratio, since if the arms are too short they can’t lock into each other, but if the arms are too long the pile doesn’t fit together well.
I’m not sure how directly you could apply this to real ants that have six bendy arms rather than two rigid ones, but it’s a nice start on the question of how ant rafts hold together.