Not sure what your point is, assuming the theory that Homo sapiens wiped out homo neanderthalensis it was before you could really argue there was such a thing as colonialism.
Most of us like to think we've grown ethically over time. Slaves were commonplace throughout history. Now we see that as unethical, societies improved.
Ah, argument from nature. Word to the wise: I used to find that fallacy compelling too, until I realized I with picking and choosing which parts of "nature" sounded right to me.
Kropotkin did it, and so do the momfluencers, and manosphere talking heads,. Even though they have widely contradictory takes.
It's not a good pillar for reason. It's another misty ideology, that only obscures your sources.