I didn’t realize that you had to actually JOIN Twitter to vote on Matthew’s poll about microbes. My apologies, and I’ll put Matthew’s poll here as well. PLEASE vote, and he’ll add our results to those on his poll from a few hours ago. Here it is, but you can vote here:
If you already voted on Twitter, please don’t do so here, as then the votes wouldn’t be independent.
Can we have an option that a “microbe” is a bacterium or similar one-celled organism, but *not* including viruses?
No. I have to put up what Matthew asked. Just give the answer closest to the one you had.
Viruses are traditionally classified as microbes. Although they are not considered to be alive.
I’d include unicellular and colonial eukaryotes as well.
I think that, “and such-like” covers these.
Reminds me of James Thurber’s description of a party he threw. As a game, his wife asked everyone present to write down as many animals as they could think of with a double “o” in their names.
It started well enough, with everyone writing down “moose,” “goose,” “mongoose,” “baboon,” etc. Then one person wrote “micro-organism” and insisted that it counted. Thurber wrote “Everyone disagreed with him and someone threw an ash-tray.”
That’s funny!
Since it’s Thurber, I wonder if The New Yorker would stick on umlaut over that second ö.
Reminds me of James Thurber’s description of a party he threw. As a game, his wife asked everyone present to write down as many animals as they could think of with a double “o” in their names.
It started well enough, with everyone writing down “moose,” “goose,” “mongoose,” “baboon,” etc. Then one person wrote “micro-organism” and insisted that it counted. Thurber wrote “Everyone disagreed with him and someone threw an ash-tray.”
Ok, this separate post works. Thanks.
Thanks for making this available. I was glad to participate.
Too late, I voted on twitter…
That’s fine; Matthew will just combine the polls. I’ll add a note that people shouldn’t vote twice.
Just thought I’d see what is said out there on the web, for “microbe.” First three from Google:
Two of the top three include viruses and single-celled eukaryotes (at least if invisible to naked eye). Wikipedia leaves out viruses.
Glen Davidson
Interesting about Wikipedia. Perhaps they were hung up on it also being an ‘organism’, and I think a lot of people don’t consider viruses to be organisms because they are not alive.
Is a virus alive if it has access to the machinery of a living cell?
How does one define “alive”?
I include them with this phrasing: “… and viruses with access to living host cells.” I think there are quite a few things that all consider to be alive but cannot either subsist or reproduce without another organism.
Are viruses in isolation that different from bacterial spores? Just waiting for the right conditions to activate and reproduce …
Anyway, I think these are interesting questions.
There is always a bit of a struggle to define ‘life’ in a way that reliably excludes things that are not regarded as truly alive but are ‘life-like’. The tricky thing is that many properties of living things are also seen in non-living things, and that makes it hard to define life.
For example, living things assimilate energy & materials from their surroundings and convert them to build & maintain their bodies. Living things do this in order to also grow, reproduce, move, respond to changes in their environment (=behavior), and maintain constant internal conditions (=homeostasis).
Problem is, one could argue that fire does ALL of those things too! So is fire alive? We must appeal to some other generally recognized things about living organisms to reject the notion that fire is alive.
Anyway, viruses do not assimilate & convert environmental energy and resources, so viruses are not alive.
This despite the fact that viruses also have other live-like properties. One especially is that populations of viruses evolve.
I follow you; but is not a virus “assimilat[ing] & convert[ing] environmental energy and resources” when it uses a host cell to manufacture copies of itself?
I think this is another one of the tough definitions/divisions.
As you note, many features of life are shared by non-living things.
I think heredity has to come into the definition of life: Self-reproducing with heredity. This is how fire is excluded. I think is how most people would define the beginning of life – self replicating entity with heredity.
I think, from the gene-centered view of life, viruses should be viewed as alive since they are able to very effectively promulgate their DNA, which is a key component of life and a key process of life.
But I claim no authority on this at all.
At some point non-life became life, so I suppose we shoudln’t be surprised that it has a fuzzy boundary, at least in some dimensions.
I think maybe the problem is that people think about what is “alive,” instead of whether we should just think about what is “life.” Maybe we’d like the two to be intimately connected, but I’m not sure that makes sense.
Is a tardigrade alive in its tun formation? One could argue about residual “metabolism,” but it’s certainly not living to the degree that an animated tardigrade is. But is it life? Sure, even if “alive” might not be so certain.
Why viruses have to be “alive” in the sense of metabolizing in order to be “life” I don’t understand. How are they not life? They evolve, they affect evolution, and they can be actively “living” under the right circumstances. If they can be alive at all, aren’t they life? Or are they life only when “alive?” It seems to me that they have to be life if they can ever live, and they don’t have to “be alive” in terms of being active at all times in order to be “life.”
What about endospores? No one seems to doubt that they are life, but they’re not “alive,” “living,” not in the sense of metabolizing significantly anyway. Seems to me to be the same way with viruses.
To me it just seems that defining “life” in biology according to bing “alive” in the usual sense of metabolizing really isn’t very useful. Endospores and viruses in my view are life that isn’t always “living” per se, but count as life because they’re part of the reproducing and evolving phenomena that we consider life to be.
Glen Davidson
It gets complicated and we here are WEIT are not the only ones struggling with it. The question of whether viruses are living or not depends entirely on the definition of life. An old French virologist (whose name escapes me) once called viruses “a borrowed life” and that may be closer to the truth than handwaving about what exactly life is.
The definition of what is “alive” may or may not include traits like biochemical autonomy, ability to replicate, a definable beginning and end, etc. I like to think of the definition as a suite of emergent properties of complex biochemistry that exhibits some combination of those traits, understanding that there is diversity in how those traits are combined or utilized. And certainly viruses themselves are diverse; members of one virus “genus”*, called Mimiviridae, can be as large as some bacteria and carries many genes thought to be necessary for something to be called “alive” – genes necessary for protein translation.
In the end whether viruses should be thought of as alive or not means little except to those who like to categorize things in strict ways. I think there is a continuum between Life and Non=Life, however one wants to define them. Viruses are part of that.
*talk about hard to define terms – how does one distinguish a “genus” of viruses?
One must first admit that this issue will run into good and challenging questions like those. But as for things like spores and dormant tardigrades, we can justly say they are in a state of suspended animation. Is that ‘alive’? Maybe not at the moment.
The virus is not itself assimilating any kind of energy or resources. Nothing enters the virus chapsule, and as far as I have ever heard very much chemically inert outside of its host cell. Viruses can carry enzymes, for example, but within the virus capsule they are completely inactive. When it attaches to a host, it is triggered to inject its genome in the cell. That material then becomes part of the host cell, hijacking the cells ability to assimilate and convert. The injected genome binds polymerase enzymes from the cell to make more copies of its genome. It makes RNA using the host cells’ RNA polymerase. It makes protein by using the host cells’ ribosomes, and so on.
We have a sample of size “one”. As my Sadistics Professer used to say, ‘You can’t do Sadistics on a sample of size “one”.’
We need to be “elsewhere”, for values of “elsewhere” greater than a dozen or so light years.
To me, if something can evolve non-trivially by natural selection, it can adapt and is alive. I therefore look on viruses as being ‘alive’, but many people smarter than I am do not.
When will you consider entities living inside a computational environment to be alive? When they can direct the construction and launch of additional computation nodes?
Likely within my lifetime ; probably within Dad’s lifetime (well, he’s sounding unwell) ; almost certainly within my step-child’s lifetime.
I really can’t choose between two false (in my opinion) choices. I don’t include viruses in my working definition of microbe so the second choice is incorrect.
I do include single-cell organisms such as the eukaryotes yeast, Plasmodium, and Giardia. I do not include small multicellular species like some arthropods. Thus, I can’t pick the first choice either.
My preferred definition is similar to the one in Wikipedia for microorganisms.
https://en.wikipedia.org/wiki/Microorganism
Agree with that. Id certainly include single celled organisms and not include arthropod. Just can’t bring myself t vote for either.
But a lot of people who are biologists will refer to viruses as a kind of microbe. The terminology has gotten murky, it seems.
I wonder if the problem is a hold-over from the days when people were aware that viruses existed, they were really tiny, but they did not know what they were.
I think that “microbe” pre-dates “virus” by a (human) generation or so. 30-40 years.
My definition doesn’t map onto either choice. IMO a microbe is a single-celled organism, including bacterial, archael and eukaryotic organisms but excluding viruses.
That anticipates exactly what I was going to say.
That’s how I’d understand it, with the confusion lying as to what counts as single celled. (Colonies and such are tricky.)
I voted A. The word precedes modern theory. A also matches the dictionary
https://www.google.com/amp/s/dictionary.cambridge.org/us/amp/english/microbe
Words evolve, too — sometimes faster’n microbes even.
Faster than online dictionaries?
Oops… I voted on both. Now nobody will be able to tell what the right answer is.
I voted
OK, much better. :->
Can we do another poll about the word “Bug”? It really drives me up the wall when I hear well-educated scientist presenters on BBC Radio 4 refer to all microbes as “bugs”!
Though in the vernacular, “I’ve caught a bug” or “there is a bug going round” generally means a virus.
You don’t work in the software business, I gather. 😉
Yes, that bugs me too.
I’ll send you that software error via a telegraph. That ought to really bug you! 🙂
They have an inordinate fondness ….
Sorry, but you set it up, and no-one else knocked it in!
I would have voted B but once, looking thru a microscope at a biopsy of a human lung tumour, completely blackened thru the patient’s smoking habit I saw an 8? Legged something crawling around. That to me was a ‘microbe’.So, like most words clear boundaries of definition are hard to come by.
I never gave much thought to what was meant by the term ‘microbe’ , since as far as I know it is not a clearly defined term.
I limited it to prokaryotes, but I guess that is just personal taste, the big chasm in life appears to be between pro- and eukaryotes.
It may even (let us hope) be the ‘Big Filter’ in Fermi’s paradox.
I somehow find it weird to call a sperm-cell a ‘microbe’.
Question about viruses being alive or dead. I’ve always heard that one cannot get the flu from the flu shot because the viruses used were dead. Can you do a piece on viruses being alive or dead?
“Dead” in this context is just a convenient term that everyone understands. “Killed” or “dead” virus vaccines are sometimes more accurately called “inactive” virus vaccines. This is most frequently done by heating the viruses, essentially destroying the function of the viral proteins making it inactive with respect to infection or replication or both.
… and they are still useful because their coats still activate the immune system, providing immunity (to some degree).
Right. The objective of the “killing” is to degrade the viral protein functions enough to destroy its pathogenicity without degrading the epitopes on those proteins that elicit the immune response.
Virus are not alive, depending on your definition, but definitely not dead either. They are only ‘not alive’ if your definition of life includes ‘independent’ self-replication.
However, they do replicate as parasites. In my modest opinion they are alive.
I wonder how a virus “decides” (becomes) lytic or lysogenic. (High school teachers and university profs who teach the material would do their students no small favor by being sufficiently competent in Latin and Greek etymology and showing why the words make sense and making them easier to understand.Re: “analytic,” “analysis,” “lysis,” etc. Otherwise it’s brute force memorization.)
“They are only ‘not alive’ if your definition of life includes ‘independent’ self-replication.”
Which definition would technically exclude all obligate parasites…
There’s no such thing as independent self-replication.
All forms of life require the use of pieces of the environment external to themselves in order to replicate. Viruses just export more functionality to the environment than most other forms of life.
The very essence of life is replication and modification, which viruses certainly do.
I don’t think there’s any coherent definition of life which would include everything but viruses.
As long as they kill Martians, I don’t really mind which definition to use !
I shall go through the Portal to Deimos Base. If I end up Knee Deep In The Dead, so be it!
A bathrobe with an attached microphone?
(I’ll get my coat)
Or a very short bathrobe.
For the record
I voted on Tw1773r.
[Tw337 shamed]
Is this a test to see how smart (or dumb) we are, or is the meaning of the word up for debate (and vote)?
I think it’s Tw**t fiend Prof FlyNose learning to use the things in the toolbox.
Neither option seems correct to me. I’ve always thought of “microbe” as a non-scientific synonym for bacterium.
Caveat: I’m an astronomer by training. I just hang out with biologists at work.
The first definition (microscopic organisms)corresponds to the coverage of microbiology courses I taught – both general microbiology for undergraduate biology majors and medical microbiology for pre-nursing students – so that’s what I voted.
I agree with others that the choices are a bit limited but I chose the second option. Why? Probably because of my job in the medical field. We have loads of “antimocrobial” stuff and I don’t think the intent is to ward off arthropds. But then again, my undergrad biology degree makes me about as much of an expert in biology as a Trump University degree makes one an expert at real estate investing.
My father taught microbiology at a university. His freshman course included viruses as a topic. His specialty was the microbiology of food. He taught about microbes that make food dangerous, tasty, or entertaining. There are viruses that make food dangerous. I had only slight difficulty considering them microbes. Perhaps the difficulty comes from considering microbes and micro-organisms to be the same catergory.
Thanks for giving us the opportunity to vote, Jerry.
Now, will Matthew tell us why he wants to know? 🙂
As a biogeochemist, I think of “microbes” as tiny things that do most of the work in carbon and nutrient recycling–so for me, it’s mainly prokaryotes and fungi. So, I think the first “definition” (for most own purposes) is too broad. But the second definition seems to implicitly exclude eukaryotes (fungi), so i can’t really go with that one either.
“…for *my* own purposes…”
There are no arthropods too small to be seen without a microscope. The smallest ones would just look like tiny specks, but still be visible to the naked eye.
So I vote for the second option. Unlike some others, I don’t exclude viruses (because they are alive by any coherent definition of life), but only if they are discrete objects. Viral genes parasitizing a host genome aren’t viruses, as I see it. They create viruses.