# The origin of complex cells

- kind: problem
- status: partial
- year: 1967
- authors: Lynn Margulis's endosymbiosis theory

**Statement.** How did complex, nucleus-bearing cells evolve from simpler prokaryotes?

Mitochondria are descended from engulfed bacteria, which is now settled after being ridiculed for years. Asgard archaea, discovered in 2015 and first cultured in 2019, appear to be the host lineage. How the nucleus and the other compartments arose is still open.

Posed 1967, Lynn Margulis's endosymbiosis theory.

## Sources

- [Wikipedia: Eukaryogenesis](https://en.wikipedia.org/wiki/Eukaryogenesis)

[Origins](/wiki/Space:origins-of-life.md) · [Life](/wiki/Continent:life.md)

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