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Comment by twothreeone | Hacker News Reader

I _think_ what they mean is it's not typically listed as a "life form" in its own right, i.e., there's no Domain under which one would classify Mitochondria - maybe just calling them bacteria would capture the article's intent?

So, the modification would be that we are living in symbiosis with mitochondrial bacteria, similar to how we live in symbiosis with our gut bacteria, rather than them being classified as "organelles" of eukaryote cells.

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Of course it is classified. In Wikipedia itself there is a phylogenetic tree listing its closest relative the alphaproteobacteria: https://en.wikipedia.org/wiki/Mitochondrion#Origin_and_evolu...

Yeah, the wikipedia entry is actually a good example.. it starts with

> A mitochondrion (pl. mitochondria) is an organelle found in the cells of most eukaryotes, such as animals, plants and fungi.

and the "classification" is introduced with

> There are two hypotheses about the origin of mitochondria: endosymbiotic and autogenous.

As others note, it is classified in the tree of life. We know approximately what kind of bacteria it evolved from, and mitochondria themselves constitute their own divergent branch of the tree of life (there are many longitudinal studies of mitochondria across species).

But if you wanted classify them based on functionality rather than evolutionary history, I'd say they're more like viruses. They have only a handful of genes themselves, and exploits the nucleus' genetic material for all the other proteins it needs to function.

That's more a flaw of classification systems though. Because even if they comprise a distinct life form does not mean they need to have a unique species. Consider lichen, which comprise two (or more!) separate "species" which becomes a meaningless distinction when they cannot survive on their own, or even if they could, not in a form recognizable in any wayas they were when they were a part of the symbiotic system

I mean at that point what do we consider multicellular organisms? Did you see what was going on with those frog skin cells and "xenobots"? Also, our gut bacteria kinda makes us a symbiote at a larger scale.

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