Ants vs. Humans

[Saddlepoint]

Okay [censored] it, I didn't want to post this, because how can you live up to How Many 5 Year Olds...?, but clearly the time is right.

The following argument has followed me from summer camp to middle school to high school to college. I've had it with dozens of people and it's never been resolved to my satisfaction.

Tomorrow morning, when the sun comes up, every single ant on planet Earth has one purpose and one purpose only: to destroy the human race. Humans receive no prior warning. The ant colonies are not working together, have no more intelligence than they would otherwise, and are still aware enough to understand that tasks like reproduction and food gathering are necessary to the war effort.

They will not stop until every single human being is dead. They would not be able to understand, nor would they accept, any kind of resolution or truce. The last ant alive will keep fighting until it's killed.

Who wins and how quickly?