2307: Alive Or Not

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Alive Or Not
Computer viruses currently fall somewhere between prions and fire.
Title text: Computer viruses currently fall somewhere between prions and fire.

Explanation[edit]

There is no universally-accepted definition of "life"; all definitions thus far proposed have either excluded some things commonly understood to be alive or included some things commonly understood to not be alive. Take reproduction, a trait commonly assumed to be essential and unique to life; by this definition, anything which cannot reproduce (including mules, worker bees, and postmenopausal women) would be considered nonliving, while anything which can duplicate itself (including computer viruses, advanced 3D printers, and fire—see below) would be considered alive.

Many more elaborate definitions of life have been attempted over the decades. Some common additional factors include:

  • Homeostasis, the ability to control an internal environment to maintain a constant state;
  • Metabolism, converting nutrients into energy and building blocks for growth, reproduction, and so on;
  • Adaptation through heredity and natural selection; and
  • Responding to the environment.

Despite all of this, the only definite definition of "life" is "something everyone agrees is alive". This comic attempts to rank several types of things by how likely people are to perceive them as "alive".

Things ranked as alive[edit]

  • Animals (normal)
  • Animals (weird ones like jellyfish and coral): Randall's categorization of animals as "normal" or "weird" is a simplified version of the Great chain of being, a philosophical framework in which humans are seen as the most "advanced" form of life, followed by a divine or otherwise justified hierarchy of progressively lesser life-forms (mammals, birds, fish, lizards, insects, and so on). Categorizing weird animals was already done in 1587: Food Rule. Alternatively, corals can be considered as lying between animals and fungi because corals, like, fungi and plants, are sessile, i.e., they "grow" in one place. Jellyfish are not sessile, but many jellyfish are the same species as corals in different generations.
  • Fungi: Fungi represent a unique lineage of eukaryotic, mostly multicellular organisms. Although historically studied by botanists specializing in the sub-discipline "mycology", modern scholarship places fungi in the "opisthokont" lineage, which contains both the animals and the fungi. Fungi, like animals, cannot make complex organic molecules from carbon dioxide, and must consume organic molecules as food to survive. Like plants, fungi are typically unable to move on their own. The various types of fungi include mushrooms, yeasts, rusts, smuts, and molds. Fungi evolution is also referenced in 1749: Mushrooms.
  • Plants: Those often green, often leafy things outside your current isolation dwelling, sometimes inside, next to the window. They are primarily distinguished from other eukaryotes by being able to use photosynthesis to convert water, carbon dioxide and energy from light into sugar and free oxygen.
  • Slime molds: Slime molds are eukaryotic single-celled organisms (so "more advanced" than bacteria). In the "plasmodial" slime molds, the "single cell" may expand to spread across several feet of territory, and weigh several pounds, while the "cellular" slime molds are most notable for their occasional congregation into macro-sized colonies which can appear to move as a single creature. It's interesting that Randall ranks them as "less alive" than fungi (which they were once thought to be), especially given some of their curious behaviors (e.g. optimizing transportation networks when presented with a collection of food flakes and obstacles).
  • Bacteria: Bacteria are one of two groups of prokaryotes, meaning cells that do not contain a nucleus and rarely harbour membrane-bound organelles. A small portion of Bacteria are pathogenic, but most are actually harmless. Bacteria's ability to convert raw materials into nutrients available for other living things makes them essential to other living things.
  • Archaea: Archaea (misspelled as Archea by Randall) is a domain of organisms, which do not fall under eukaryotes or bacteria. They are single-celled organisms that lack a nucleus, and were initially thought to be ancient lineages of bacteria (i.e. archaeobacteria) found in extreme environments similar to the early Earth, which is probably why Randall ranks them as "less alive" than bacteria. However, it is now known that they live pretty much everywhere that regular bacteria do, and that they have very distinct biochemistry from bacteria; they are actually more closely related to eukaryotes (i.e. slime molds and up) than bacteria are.
  • Viruses: Viruses are infectious agents consisting of a genome surrounded by a protein or lipid shell. When a virus contacts a cell, it delivers its genome inside the cell which causes the cells' reproductive machinery to create more viruses. Since viruses are incapable of reproducing without the aid of larger cells, it is often debated whether or not they are actually alive. Randall has ranked viruses as "alive" but on the lowest possible rung of such; indeed, many biologists say viruses fall in a gray area, or that the question is arbitrary and non-scientific. By another criterion life on Earth is defined by the presence of extremely long molecules that can be replicated (copied). Every organism above viruses contains both DNA and RNA. Viruses only contain either RNA or DNA. Nothing below here contains any (biologically active) DNA or RNA.

Things ranked as not alive[edit]

  • Prions: Prions are misfolded proteins that cause other proteins to misfold. They are most famously the cause of various brain diseases such as "mad cow disease", and may be involved in Alzheimer's disease. Similarly to viruses, prions require something else to replicate, but unlike viruses, they do not possess a nucleic-acid genome or any other means of carrying heritable information, and they do not alter the cell's production machinery, but rather interact with proteins which are already made. In that sense, they're more like a particularly tricky kind of metabolic waste product or pollution.
  • (from title text) Computer viruses: A piece of code which hijacks computer systems to replicate itself, named by analogy to biological viruses. Strictly speaking, they're just a particular encoding of information, usually stored in electromagnetic media (although there's no reason one couldn't be stored on punch cards). Randall ranks them as "currently" more alive than fire, because they do carry "genetic" information (which anti-virus programs can be programmed to look for, analogous to vaccination) and some are capable of modifying themselves to adapt to new environments, but less alive than prions because they only operate within information systems. However, if a virus were able to e.g. hijack an electronics factory to start making flash drives and memory cards that carry the virus's code, then perhaps it might move up in the hierarchy.
  • Fire: Fire is a common example of something which meets many common definitions for life; it grows, reproduces by spreading seeds (sparks), and consumes energy and excretes waste (ashes and smoke) by the same net chemical process as respiration. However, while fire can be a necessary part of the life cycle of other organisms (e.g. redwood trees), it does not maintain a constant environment within itself, nor does it perform anabolism, the construction of larger molecules from smaller ones. Respirating life-forms use helper molecules to moderate the oxidation reaction into small steps to produce useful units of energy, rather than letting it all happen at once to produce heat.
  • Clouds: Random shapes taken by clouds may resemble animals and other objects, but arguably they are not alive in any sense. Things like tornadoes and hurricanes, on the other hand, can meet some definitions of life: they maintain homeostasis, actively seek and consume energy, and occasionally reproduce. Cf. Fire above.
  • Fossils: Fossils are the petrified remains of once-living organisms, so in that sense they are more connected to life than "regular rocks", and some may hold DNA that could theoretically be used to clone the fossilized life-form.
  • Rocks shaped like faces: Humans have an extremely advanced capability for seeing patterns, and one of the most powerful patterns we seek is faces, so much so that we see faces even where they don't exist (a common form of pareidolia). Humans instinctively anthropomorphize any object which vaguely resembles a face as having a sense of attention and mood, and so a rock shaped like a face would likely be treated differently than a rock not shaped like a face. Randall does not distinguish between rocks intentionally carved to look like faces (such as the famous Moai sculptures) or rocks that happen to look vaguely like faces under the right lighting conditions (such as the famous Face on Mars.)
  • Regular rocks: Modern taxonomy originates from Carl Linnaeus, who categorized all objects on Earth as animals, plants (often stated as "vegetable" in quiz games like Twenty Questions), or minerals. Minerals are most obviously not alive, although some cultures and works of fiction have creatures that turn to stone and will return later to life, and some people keep rocks as "pets".

Interestingly, the vertical line linking the categories extends beyond both the most-alive and least-alive things, making one wonder what Randall might think is more alive than "normal animals" or less alive than "regular rocks". In the latter direction an explanation might be that shortly before this comic the scientific press wrote about heat-resistant bacteria that live in the desert and slowly eat regular rocks generating their own water in this process making even the sand in the desert partially alive.

Transcript[edit]

[A chart consisting of vertical line, with 14 dots and a horizontal dashed dividing line drawn across the list a bit below the middle. Each dot has a label to the right of the line with a line pointing to the dot they belong to. Above and below the dividing line is a label with a broad arrow pointing up above and down below.]
Up arrow: Alive
Down arrow: Not alive
[Dot labels from top to bottom above the dashed line:]
Animals (Normal)
Animals (Weird ones like jellyfish and coral)
Fungi
Plants
Slime molds
Bacteria
Archea
Viruses
[Dot labels from top to bottom below the dashed line:]
Prions
Fire
Clouds
Fossils
Rocks shaped like faces
Regular rocks


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Discussion

I'm pretty sure high-pressure fire hoses belong on this scale60sRefugee (talk) 21:47, 15 May 2020 (UTC)

What about wacky waving inflatable tube guy? 172.68.38.124 00:41, 16 May 2020 (UTC)

Funny, for once viruses are said to be alive. That's new... 141.101.107.138 22:01, 15 May 2020 (UTC)

Definitely new, and extremely angering! I could scream... 172.68.143.30 22:47, 15 May 2020 (UTC)
Jup. The nex disgusting piece of antiscience after Wednesday´s nonsense about handwashing helping against respirational diseases. I think Monroe has caught a bug from Potus Donald. --141.101.69.33 07:44, 16 May 2020 (UTC)
There was nothing unscientific about either one. The cold is spread in part by contact--it's why we cough into our elbows, not our hands now--it reduces spread. And whether or not viruses count as alive is debatable, not obviously wrong. They do have genetic material and reproduce, and you can kill them, making them inert in various ways. -->
But even if he had been incorrect, comparing someone to some other hated figure for some much smaller slight is just Godwin-lite. And, like the original, it contributes nothing of value to the conversation. In no way does it help determine who is correct. Trlkly (talk) 16:49, 18 May 2020 (UTC)

Do we want to bicker over the placement of the line (like "Why is it below viruses"), or the order things are placed in (like "Why are slime molds below plants")? GreatWyrmGold (talk) 22:06, 15 May 2020 (UTC)

Oh, go on. If you insist. You go first, unless you already have. ;) 162.158.154.31 22:46, 15 May 2020 (UTC)
Seconded, I'm most interested which criterion (even a numeric one, as the diagram is suggestive of) Randall used. 162.158.158.163 09:43, 16 May 2020 (UTC)

True fossils have remineralised so generally do not have DNA left. They are merely the shadow of a previous life.

So fossils are closer to "Rocks with Faces," well, for the ancient vertebrate fossils anyway? Nutster (talk) 15:36, 16 May 2020 (UTC)

Surprised no one has noticed the typo yet. It's 'archaea', not 'archea'

(Sign yourself(/ves), "True fossils" and "Surprised"?) I disagree. It's 'archæa'... 162.158.154.31 22:46, 15 May 2020 (UTC)

Poor English and a mistake. It should say... "...discussion about *whether* virus*es* are alive." Also the (covid for starters) is wrong. Covid19 is the disease caused by the virus (as mentioned in the line above) not the virus itself

I am disappointed that sponges are not mentioned as an example of weird animals. I mean, come on, way weirder than jellyfish. But it is good that viruses get the recognition they deserve.Jkrstrt (talk) 13:34, 16 May 2020 (UTC)

When looking at viruses, I consider them made of the things of life (proteins, lipids, nucleic acids), but are not actually alive as they have no metabolism and can not reproduce on their own; they need to co-opt the protein production facility of truly living cells in order to reproduce. Without a host, they just sit there (or maybe blow around on the wind). Also without metabolism, they can not starve to death, like bacteria and other single-cell organisms that get into the wrong environment. Nutster (talk) 15:36, 16 May 2020 (UTC)

Agreed that the lack of metabolism is a big thing. On the other hand, all organisms need an acceptable habitat to be able to reproduce, and viruses are no different: their habitat is their target cells, where they can reproduce like mad. Furthermore, viruses can be infected and killed by other viruses, namely by virophages, and it's hard to see how they can be killed if they weren't alive to begin with. Whether they're "alive" depends only on one's definition of the word; it can be interesting to discuss this because it reveals what people think "alive" means, but not because there's a true answer. DKMell (talk) 22:18, 18 May 2020 (UTC)
technically, virophages do not directly infect other viruses, they rather co-infect a cell and use the reproduction machinery of the other virus, blocking it at the same time... 162.158.93.27 guest from outer space

Well, this raises the question where the sun (or any main sequence star) fall on this list. Is it just a really big thermonuclear fire?

This is not a COVID-19 comic. Just because it is biology-related, doesn't make it a COVID-19 comic. I have removed it from the category and its mention in the explanation.172.69.34.38 07:33, 17 May 2020 (UTC)

Of course it is. The whole idea about this comic is to spark the discussion if Virus (covid) is alive or not. I put it back. --Kynde (talk) 21:59, 17 May 2020 (UTC)
I fully disagree, this comic could have been published in previous years. This is only tangentially related to COVID-19, and is a general discussion about "life". Viruses are only barely mentioned in this comic. 172.69.34.38 23:26, 17 May 2020 (UTC)
Agree it shouldn't be classified as COVID-19, but then there's a bunch of others that should be removed from the category: 2278, 2283, 2289, 2292, 2293.141.101.107.78 08:34, 18 May 2020 (UTC)
I wouldn't consider this comic about COVID-19, either. Elektrizikekswerk (talk) 13:49, 18 May 2020 (UTC)
OMG - this comic is centered around virus being alive or not in the midst of a virus pandemic that all comics the last two months has been about, and you cannot see the connection! Of course this is inspired by the previous comic about corona, with virus that speaks to us! --Kynde (talk) 09:47, 19 May 2020 (UTC)
Nope. Granted, there _may_ be a connection since it would indeed be fitting to the last comics and the current world situation. However nothing in the comic leads to the conclusion that it actually _is_. Unless you actually _are_ Randall there is no way you can actually say that it is "of course inspired" by the event/previous comic. It's all like "Sad", again - you are seeing "obvious" connections where there are none. Like 172.69.34.38 said, the comic wouldn't be less funny/informative/whatever without this connection. Elektrizikekswerk (talk) 11:00, 19 May 2020 (UTC)
I disagree that this comic is inspired by or a "continuation" of the previous comic. Randall likes to anthropomorphize things, but that doesn't provide a lead-in to whether they are alive or not. These two comics are separate topics. 172.69.35.47 23:36, 19 May 2020 (UTC)
Well I still think this is a clear continuation of the previous one and no matter what is a take on virus being alive or not, in the midst of a viral pandemic. Cannot understand the objectiopn at all to this being a COVIS 19 comic. But this disucssion is Not (alive). --Kynde (talk) 14:09, 20 May 2020 (UTC)


Somewhat disappointed that he didn't include any fictional items such as golems. For that matter, where to place Alexa? Cellocgw (talk) 10:51, 18 May 2020 (UTC)

I’m surprised this doesn’t include Schrödinger’s Cat at the origin. 162.158.91.77 14:53, 18 May 2020 (UTC)

Shouldn't Schrödinger’s Cat be in a super-position on both sides of the line? A pair of grey dots above and below the demarcation line. Nutster (talk) 11:45, 19 May 2020 (UTC)

Missed joke opportunity: which type of cloud? because one type of cloud has AI in it..

Why are slime molds below plants and fungi? They actually move.--172.68.189.241 17:05, 18 May 2020 (UTC)

I assume the reason mushrooms are so high up is because of https://xkcd.com/1749/

What? No mention of "mostly dead is slightly alive"? For those that don't get it - go watch The Princess Bride :) 162.158.7.151 05:51, 25 May 2020 (UTC)