It's an interesting story told from an interesting POV. The well rehearsed philosophy that we will eventually bring our own destruction upon us, is a nice and quick way of painting a background story.
I do however have a few issues with the characters becoming flat at times. You need to characterize them a bit further as your story evolves around story drive. None of the characters in this film stood on their own so you have to work on that.
Technically the artistic style is nice and lively with vibrant colours and the needed depth. You can however work some more on the animation of your characters and make them more fluid and integrated. It did feel a bit like pieces of cardboard cutouts moved on a background.
The sound needs some working too and tweaking in the channels. The forest needs to come out further and you need a broader sound picture to make the world come alive. Could also drop the music down a few notches to work a bit on sub level instead of up front.
I like this and it's a nice start to hopefully a good story. Keep working on your skills and story telling and I'm sure you'll make a splendid series :)