Well I do know there is a parasite that gets on a ant and it turns it into a sort of zombie.
And there is a grub, that actually leaves *** that ants are attracted to and they eat it thus they pick up that parasite. That parasite then goes through the ant's body, the ant stays at the end of a grass blade or whatever, and the slug comes up and eats the ant. Then it goes back around again.
I did not watch the video. I am merely remembering (and paraphrasing) information I once remembered hearing about ants.
I find ants, insects in general, fascinating. Mainly because ants are very militaristic!