I could not find if such a thread already existed. If it does, let me know and I’ll merge this with that.
The topic of environmental adaptations has come up many times now in the past years, but I’m not sure if any concrete concept has been laid out for it. What we do know is that we want each cell to have a range of values, for each environmental variable, that it can survive in normally. The question is what penalties does it face when in a biome outside of those ranges? Here are some of the suggestions for it, and my thoughts on each approach:
Damage over time. If you live in a biome outside of your environmental tolerance, you take damage over time. The damage over time scales up based on how far out of your range it is, and how many of the environmental variables are hazardous to you.
- I think this one is an easy way of preventing unadapted species from living outside of their range. The downside is that even living even slightly outside of your range means damage over time, which probably will lead to your death (unless you are very small and reproduce very quickly).
Increased osmoregulation cost. If you live in a biome outside of your environmental tolerance, your cell’s osmoregulation cost is scaled up. The amount it’s scaled up depends on how far out of your range it is, and how many of the environmental variables are hazardous to you.
- This is a technically more realistic approach, since cell membranes are reactive to the environment, so for example if the surroundings become more acidic they will spend more energy preventing that acid from getting inside the cell. A benefit of this system is that it means that highly energy efficient cells can live slightly outside their range without much issue.
Reduced efficiency of all organelles. If you live in a biome outside of your environmental tolerance, the efficiency of all your organelles is scaled down. The amount it’s scaled down depends on how far out of your range it is, and how many of the environmental variables are hazardous to you.
- Again, I like this approach because it allows for energy efficient cells to survive slightly outside of their range, making it easier for successful species to colonize adjacent patches. The way this differs from 2) is that this gives a bigger penalty to living outside of your range. In 2), you simply have a higher ATP expense but everything else is normal. Everything is less efficient, from your motion producing organelles to your energy producing ones.
Let me know if I missed one of the past suggestions.
Although I was originally for Option 1, after thinking more about it I think I’m more in favour of either Option 2 or Option 3. Plus, Option 2 or Option 3 would result in damage over time anyways if the penalties are severe enough.