Do you happen to have a link to one of these papers? Sounds interesting

The problem is that parasites can range such a gamut that range from selfish genetic elements like transposons all the way up to like, head lice and remora. It's not clear where the line is between organisms and not, because it's really a gradient that depends on your opinion to draw a line. "Capable of living on it's own" is a good line to draw, though, when you're asking how many genes you need to live. It would be like asking how much money you need to live in NYC and including people in a survey who live with their parents. Not totally relevant to the question being asked.

Would replication of RNA/DNA not be sufficient to be considered an organism?

I see why the parasite/virus case is similar. Does the difference stem from the necessity of a host for viral replication?

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A chair requires a very specific environment to reproduce. Inside a carpentry shop with a human carpenter capable of measuring, cutting, and machining new parts to assemble, or otherwise a factory designed to create more chairs. /s

Sounds a lot like a retrotransposon, which aren't particularly dangerous.

Virologist and professor Vincent Racaniello refers to viruses as “obligate intracellular parasites.”

One of the fascinating areas of research is in using bacteriophages to break up biofilms. https://www.frontiersin.org/articles/10.3389/fmicb.2022.825828/full

In those conditions humans are dead, so they do not fulfill the definition of life.

A virus has no ability to reproduce, and as such it is not life.

For that matter, what about a prion? Does nothing when not in the presence of similar amino acid chains that are in a vulnerable conformation, but makes more of itself when those resources are available.

Then again, prions don't breathe and eat and grow, and that is how we know they're not alive.

There is another organism on this planet that follows the same pattern. Do you know what it is?

Viruses aren't dead but they don't fit the definition of alive either, it's just a coded set of genetic information that uses the cells processes to reproduce. They float without direction until they hit a cell they can hijack

Viruses require very specific environments to reproduce (the inside of the right kind of cell), but so does humans. Put humans in 2000 degrees, and they won't reproduce. Put them in the vacuum of space, and they won't reproduce. Without food, humans won't reproduce. Without water, humans won't reproduce. How is that fundamentally different from viruses?

A much more convincing argument for viruses not being alive is that they don't have a metabolism.

It really depends who you ask. Some consider viruses to be alive, others do not.

True, a virus can't function unless it's inside a cell with access to those nutrients/cofactors, and existing proteins and other components. But a bacteria also can't function unless it's in an environment with appropriate nutrients/cofactors and existing proteins and other components. The only difference is that those proteins etc already exist when the bacteria is born (divides into daughter cells), while a virus has to go and find them. Does that difference define life?

But then, if you consider a virus to be alive, what about self-replicating plasmids? They're really not much different from a virus. What about transposable elements in a genome? Are they alive too? They're not much different than a virus in latent phase.

The definition of life is something that sounds like it should be easy, and high school textbooks do give a precise definition. But the reality is a lot more complicated and murky than it seems.

Not really. It was grown in highly specific conditions in a lab. If it got out, it would probably be broken down incredibly quickly.

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No, but a virus doesn't have the ability to reproduce. It has the ability to be reproduced. But so does many things, such as chairs, phones, books, and possibly other stuff. Much like a virus however, neither chairs, phones or books can reproduce.

Yup. Its theorised that that was how life originally came about too: self-replicating nucleotide structures. All the other stuff came afterwards as imperfect copying resulted in changes (and increasing complexity) over time.

Eh. Not really any more than there is a concrete definition of "species".

Lots of biologists don't refer to viruses as organisms, but there's a fair argument that they're no less alive than any other parasite.

I'd say, noting this is tangential to my field of study, that the (EDIT: agreed upon) minimum requirement is a cell membrane. Viruses may have capsules, but it's not quite the same. I believe this to be unnecessarily arbitrary, but it's consistent with keeping viruses out of the alive category

It’s just an RNA chain really.

The original bacteriophage virus used to harvest the first chain only infected certain bacterium such as E. Coli, fwiw.

The actual replication environment is highly specific and required special solutions.

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> doesn't really represent an organism because it requires the mechanisms of a cell to replicate.

Is there a specific definition of "organism" that includes this requirement? Not trying to be snarky I'm genuinely curious. I always thought that "organism" just meant a unit of "life" which just requires the ability to reproduce, and doesn't include the mechanism.

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You were probably contemplating primordial, when you should have been considering soup.