Interesting.
It is an interesting movie and definitely a nice, fresh sort of style. I liked how there was lots of white space and then the little society was all drawn in the middle on that one 'hill' and then the valley sort of thing. The buildings were nice and cartoony but the soft colors gave it a more serious, artsy feel. What I really like is how this movie was all presented.
What I don't like is how simple the story is. It doesn't really live up to the description you gave it... yes, I can see how the two simple houses really built up and it became a city, and then when the city was gone the people still needed to eat. But where did you show the people NOT getting their basic needs met (during the 'larger and more complicated' stage)?
All the parts of this flash seem good, but something did not translate from the story concept to the art...