On May 5th, 1818, Karl Marx, hero of the international proletatiat, was born. His revolution of Socialist theory reverberates throughout the world carries on to this day, in increasing magnitude. Every passing day, he is vindicated. His analysis of Capitalism, development of the theory of Scientific Socialism, and advancements on dialectics to become Dialectical Materialism, have all played a key role in the past century, and have remained ever-more relevant throughout.
He didn't always rock his famous beard, when he was younger he was clean shaven!

Some significant works:
Economic & Philosophic Manuscripts of 1844
The Eighteenth Brumaire of Louis Bonaparte
The Civil War in France
Wage Labor & Capital
Wages, Price, and Profit
Critique of the Gotha Programme
Manifesto of the Communist Party (along with Engels)
The Poverty of Philosophy
And, of course, Capital Vol I-III
Interested in Marxism-Leninism, but don't know where to start? Check out my "Read Theory, Darn it!" introductory reading list!
Communism is human nature. Communism existed in the Americas and Australia for thousands of years. It probably existed in the rest of the world too before agriculture, but our historical records from other regions were destroyed. By contrast, Australia has the most intact ancient histories in the world.
It's important to draw a line between Primitive Communism and Communism as a post-Socialist society. Primitive Communism is founded upon small, isolated communities, while Marx's Communism is one of large industry run along a common plan, democratically, to suit the needs of all.
What's more accurate is to say that what's considered "Human Nature" changes alongside Mode of Production. It was indeed "Human Nature" to have cooperative, communal units, but it is also "Human Nature" to produce under Capitalism, and still further "Human Nature" to move beyond the discordant production of Capitalism to a cohesive Socialist, and eventually Communist, society.
That feels like some noble savage stuff. Societies aren't different because they have different technology with the same economic system. It feels like you're saying indigenous societies wouldn't have been able to industrialise without changing their political system radically.
But indigenous societies made conscious political choices about how to structure society, and drag believes they had the political structure required to adapt to industrialisation without losing their political system.
Drag doesn't buy the distinction you're making between indigenous communism and industrialised communism. Drag doesn't think the difference is relevant to whether something is communism, and the only way drag could see it being relevant is through the noble savage trope.
Societies with different technologies would tend to have very different social and economic systems. Indigenous societies that industrialise do end up changing their political systems because of this.
Industrialised communism does not exist, at least yet, but any industrial society will necessarily need to organise itself in a very different way from a primitive society (whether communist or not).