We live in a world of so, so, so many ants. Did you read that ants post I put on Kottke? There’s just gazillions of ants ALL OVER THE PLACE.
“The vortex of ants” is a circular mill where a group of ants (sometimes hundreds to millions of ants) get separated from the main swarm and ended up following each others’ scent in a circle. It’s called the death spiral because they continue to go in circles until they’re exhausted and die.