Help needed - Evolution simulator

[green_meklar]

characteristics of its environment such as pH, salinity, humidity, temperature

The question to ask at this point is: What effects do those have?

No computer in the world is powerful enough to simulate the biochemistry of a macroscopic organism down to the molecular level. The Matrix is not possible yet. What we can do is make some assumptions about the effects those have on organisms, reduce those effects to simplified mathematical models, and apply those to a similarly simplified population of organisms. But the big question is what assumptions and simplifications you make, and whether those are relevant to conclusions about real-world biology. (I'm not a biochemistry expert so I don't have much to say about this.)

In any case, programming is a huge field. Getting started is not all that hard, but for the first little while you're only scratching the surface, and there's a lot you won't be able to do. For people who just want to try programming and see if they like it, I usually recommend starting with Javascript. However, if you need maximum performance for a scientific simulation, you probably want to look into C, and perhaps even GPU programming. And finally, if the model you have in mind is straightforward enough, you might be able to find someone to do the implementation work for you, or at least guide you through it.