(Written by a younger me, aka. a jerk who took himself far too seriously)
Quite some time ago I spent time thinking about what separates Life from Non-life. There are many features that immediately spring to mind, but they all seemed to have plenty of exceptions. Consciousness? Plants have no sensory organs. Reproduction? A simple machine can easily duplicate itself. Organic molecules? Created all the time by simple chemical reactions. DNA? RNA creatures might object to that. A soul? I’d prefer an answer which we can verify actually exists. And so on…
At about this time I stumbled onto a small evolution simulator called “Primordial Life”, created by Jason Spofford. It reproduced small ‘Biots’, which used simple hereditary and mutation to fight for survival on the computer screen. I spent fascinated hours watching the life cycles of these simplistic collections of lines, saw entire ecosystems come and go… but eventually I got bored, and went to turn it off.
But I hesitated. These ‘creatures’, despite being nothing more than a small collection of variables rendered on the screen, had spent hours developing on my computer, had descended from creatures that had survived mass extinctions and developed brilliantly to the environment they lived in… and I was about to simply delete them and destroy their entire universe.
And I decided then what defined life, at least for me: Evolution.
The struggle of each population to survive, individuals changing randomly but being directed and guided by natural selection, made the biots more than mere lines of coloured pixels.
They might have lived in a tiny, restricted world, limited to the 2 dimensional space on the screen, but how different is that from real life, which lives on a tiny planet, limited to the 3 dimensional space it can see and interacts with? It’s easy enough to argue that the biots could never evolve things like intelligence, but this is a limitation of their environment: unlike real life, their mutations are limited to a small set of variables.
So I decided to see whether I could make an evolution simulator on a much more massive scale. A full sized 3D world with completely mutable creatures, a hereditary system, resources for the creatures to compete for and no fitness function. The only thing that would determine how well an individual survived would be its ability to reproduce. I believed that with all these simple things set up, the complexities of evolution; including punctuated equilibrium, convergence, sexual selection and geological separation; would visit my world. And if I was lucky, some people would see in what I had created the same thing I saw back then in the biots.
Welcome to Species.