On a caravan trip recently, we had an ant invasion. To stop it, I laid down liquid ant killer around a circular vent hole in the floor of the caravan, where they seemed to be coming in.

As I laid the liquid down, the ants immediately headed for it, drank/ate it and, after about 5 minutes, the majority of them were unmoving (dead, asleep?). There were about 100 bodies there - as it was evening, I decided to leave them there and clear them away in the morning.

But when I woke in the morning, all the bodies were gone!! How did that happen? And why?

It seems to suggest that other ants arrived, saw their dead 'comrades', waded through the ant killer to get them and then dragged the bodies back through the liquid to their nest - is that possible? But why?

As an aside, the ants also seemed to learn that the liquid was poisonous as we didn't see another ant for 2 weeks.

possibly they would gain from the breakdown of the victim's body - minerals, etc. also maybe contents of vomit - spreading the spores. this would presumably apply only to the ones that look 'innocent' (& taste ok).