Techno2000:
rossum:
Techno2000:
Where did the other organisms come from?
They were the population of chemotrophs. Haven’t you been paying attention? We started with 100% chemotrophs, and then some evolved to be able to get at the chemicals inside other chemotrophs.
rossum
You are making up all this stuff as you go along…right, rossum ?
No, it’s exactly the answer I’d have given.
The same organism drifts into different environments. Due to these differences, there are different selective pressures. They evolve in response to those pressures.
The first apparent changes are so incrementally small that you’d still consider the different groups as different variations of the same species.
Then the changes become more apparent and you’d then consider them different sub-species of the same species.
Then the changes become significant enough that they’re considered a different species all together.
All happening over time, in response to the forces within their different environments.
*Worth noting - what most often happens over evolutionary history is that the organism drifts into an environment with so much selective pressure that it’s too much for the organism to slowly overcome. The organism becomes locally extinct in that area.