"And I was wondering, 'What exactly was going on there? Why were they carrying some of the ants?'" he recalls.
It turns out, those transported ants weren't dead — they were injured.
And they don't eat them? That's really fucking cool.
That's a really complex behavior, even if we take into account that complex behavior routinely arises from systems of relatively 'simple' agents. Because it's so much more than 'return invested biomass to the colony,' I wonder how such a trait developed. What kind of selective pressure was put on the ants to develop such a behavior?