This started as a random thought many years ago where I considered if it were possible to create digital creatures that evolved. It started out as a simple project but quickly became very complicated, although that is what I would have expected. My first attempt was based on a grid world and the creatures evolved to find food and compete. The system worked although it was ugly and unidirectional. The higher level creatures evolved to be large formless masses that simply drifted in one direction. 

My second attempt involved Microsoft’s XNA studio which looked much better than the first attempt. In that version I needed to work out the collision detection, rotational math, physics, etc. As such it was not an optimal solution and was very processor intensive. I also had built it before fully deciding on the DNA structure and behaviors. 

This, the third attempt, is built on the Unity2D platform (with a few 3D elements). I decided to spend a lot of time working out the structure, DNA, behaviors, mutations, and environment rules before moving to the next step. I am pleased with how it turned out this time and have tried to incorporate one rule, let the creatures evolve naturally. I cut a corner or two to make it a bit more interesting, like how they favor symmetry or are more likely to react to food. I did not tell them how to react, they can run from food if they so choose, just that they are more likely to react to a food signal. I hope you enjoy it!