Pyrrha and Deucalion, by Fontana.

So you remember how Pandora was the first woman? By the time her daughter, Pyrrha, had grown up, the whole world was populated with humans (we're prolific little buggers, aren't we?). The age in which the Earth became so populated was the Bronze Age, "when cruel people were inclined to arms by not to impious acts" and Zeus really wasn't a huge fan of this age, mostly 'cuz they weren't doing nearly enough propitiating (never forget the propitiating!). So, he decided to flood it so that everyone would die and he could start over. But Prometheus (yeah, you saw him before bringing fire to humans, and even making them out of clay in some versions) was Forethought, so he let his son, Deucalion, in on the secret. Deucalion was married to Pyrrha, so she got in on it, too. And together, the two of them got to work on a huge chest. Not quite an ark, but close enough. At any rate, they stuffed it full of provisions and jumped in. Zeus got to raining on Greece, and just about everyone perished very soggily (except for the few people who made it to the mountains in time). Of course, Deucalion and Pyrrha made it out (afer nine days and nine nights floating over their old haunts), and once they did they made a temple to Zeus of Escape and Zeus thought, "Hey, these guys aren't so bad. And they make yummy sacrifices." So he sent out Hermes to the couple to let them do what they would. And they wanted to replenish the earth with men. So Zeus, being down, told them to throw the bones of their mother over their shoulders. Eww!? But no, clearly they weren't gonna go get Pandora from Epimetheus (with whom, I'm sure, she was still happily living), instead they picked up stones (the bones of their mother, Earth) and threw those. And where Pyrrha's stones fell, women were born, and where Deucalion's stones fell, men sprang up. Actually, as a cool sidenote, the word for "people" in greek is derived from the word for stone!

Wanna read the original? Check out Apollodorous in the Perseus Project.

Also, you should feel free to draw connections between this and the story of Noah's ark.