There’s a new episode of PBS Eons.  This one is about the Hell Ants… an extinct group of ants that might give us clues about eusociality.

This ancient species had the same six legs and segmented body that we’d recognize from an ant today. But it also had a huge, scythe-like jaw and a horn coming out of its head. This bizarre predator belonged to a group known as “hell ants.” But they’re gone now, and we’re still trying to figure out why.