I finally got a concept for my game.

As I stated in my previous post, I want to make a browser game that is managed by a server (not a simple HTML5 game).

The player incarnate an evolution. An evolution is a  vector on a 2D plane.

On the game surface there is a timer with a reset button.

Every time someone hit that button, the target specie evolve according to the vector of the player.

Your aim is that the specie is the nearest of the half-line from the start following your vector.

PS: I hate this theme. It took me a lot of time to even get an idea.