[HN Gopher] An animal that doesn't breathe oxygen
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An animal that doesn't breathe oxygen
Author : ksec
Score : 239 points
Date : 2020-03-23 09:55 UTC (1 days ago)
(HTM) web link (www.cbc.ca)
(TXT) w3m dump (www.cbc.ca)
| DarkCoder wrote:
| Great News
| tantalor wrote:
| > steal energy molecules called ATP from their hosts
|
| Not unlike a virus which also lacks their own metabolism.
|
| This will raise similar question as whether it is "alive".
| swebs wrote:
| I doubt it. It's a multi-cellular organism that is capable of
| moving on its own. I don't think anyone will claim that it is
| not alive because it can't produce its own ATP.
| jshevek wrote:
| A virus also lacks the ability to even duplicate its own
| genetic material without the help of a host cell. The set of
| features a virus lacks is much larger.
|
| On the other hand, all animals depend on another form of life
| to provide energetic molecules. As this organism (presumably)
| depends on ATP from another source, we depend on energy
| providing molecules like carbs, fat, protein.
| vadiml wrote:
| This is proto-zombie animal
| willart4food wrote:
| I could have introduced them to my first ex-wife!
| kazinator wrote:
| "Scientists discover a clump of anaerobic cells that steals ATP
| from a host, and call it an animal."
| jshevek wrote:
| Several comments seem to suggest this is not really an animal,
| and I don't yet understand why. Is that your intention? If so,
| why is this not an animal?
| kazinator wrote:
| The point is that "discover an animal that doesn't breathe
| oxygen" is purely a word semantic game.
|
| Not breathing oxygen isn't interesting; anaerobic bacteria do
| that. If we call those "animals", then we already have non-
| oxygen-breathing animals.
|
| By the way, the following is from ten years ago:
|
| https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2907586/
|
| If _that_ discovery found "animals", then it is rightly the
| first one.
| jshevek wrote:
| > _The point is that "discover an animal that doesn't
| breathe oxygen" is purely a word semantic game._
|
| I still don't understand your point. This species is an
| animal, according to accepted taxonomy.
| jb775 wrote:
| Hillary Clinton?
| dang wrote:
| Please don't post flamebait to HN. We ban accounts that do
| that.
|
| If you wouldn't mind reviewing
| https://news.ycombinator.com/newsguidelines.html and using the
| site as intended, we'd be grateful. The idea is thoughtful,
| curious conversation.
| [deleted]
| jonplackett wrote:
| This was really exciting until I read the bit where it says it
| just steals ATP from the host. Thought it could be a whole new
| way of life but looks more like a clever parasite hack.
| mcguire wrote:
| I saw the punch line coming when I read that it was a parasite.
| That being said, it's an extreme form of parasitism.
| jjeaff wrote:
| I guess it depends on how you look at it. Many scientists say
| that viruses aren't alive because they can't reproduce. But
| they actually do reproduce by parasitizing a host.
| bluejellybean wrote:
| A virus isn't considered life because they do not follow all
| of the characteristics of life. This lists consists of:
|
| order - meaning systems of cells
|
| response to the environment - can sense, integrate senses,
| and response
|
| reproduction - can create offspring
|
| growth and development - do the cells grow and mature
|
| regulation - there are mechanisms in place for heat control,
| thirst, etc
|
| homeostasis - are able to maintain environmental
| equilibrium/steady state
|
| energy processing - have the ability to convert sun to energy
| or process something chemically todo so.
|
| If you go through this list, it's quite clear why a virus
| doesn't make the criteria for life. There is no order, they
| do not respond to the environment, there is no cell growth or
| development, they do not have mechanisms for heat, thirst,
| etc, and they do not maintain an environmental steady state.
| DoctorOetker wrote:
| I think those are great _rough criteria_ through which one
| could perhaps arrive at a distinction between virusses and
| other life forms.
|
| But let's consider the original concept of the feature
| based _tree of life_ , which with the advent of genetic
| sequencing was eventually shown to contain many errors, and
| to really be a _graph of life_ with a strongly discernible
| _spanning tree_.
|
| So if genomes turn out to be a better navigation instrument
| than behaviors or features, and given how modern
| understanding of the evolution of life through natural
| selection, it would appear a better definition for life
| forms would be to say: patterns in physical nature that can
| thrive in specific niches (often relying on the presence of
| other such patterns) _having one or more nontrivial /
| unbounded chemical information stores (say polymers) the
| contents of which undergo natural selection or the
| evolutionary algorithm in the environment according to
| physics_.
|
| So prion would not be life forms since their number of
| chemical states are trivial or bounded, while viruses would
| still be lifeforms under my definition since their RNA or
| DNA sequences are non-trivial and in some sense unbounded
| (their genome could grow or shrink in size over
| generations).
|
| Also consider that just like living organisms can die
| because of say UV-C radiation, so can viruses be
| inactivated by UV-C radiation...
| mncharity wrote:
| > A virus isn't considered life because they do not follow
| all of the characteristics of life. This lists consists of:
|
| The list is regrettably a "science-education-ism". My
| phrase - I don't know of a real one. Anyone? A divergence
| between science-education community practice and science
| community practice. A rather dramatic one. In actual
| science practice, "is it alive?" isn't an interesting
| question, and has none of the importance science-education
| content often places on it. And people who actually work
| with viruses, consider them alive. It's perhaps regrettable
| that so much education content presents the list as
| science, rather than as an education device. And even as a
| device it has difficulties, as it doesn't deal well with
| the richness of biology, including around parasitism, and a
| binary sort just isn't useful.
| meragrin_ wrote:
| If there is no order, response to environment, or
| growth/development, how can they reproduce?
|
| Assuming reproduction is a characteristic they possess, why
| is that different from the others they do not possess?
| Reproduction relies on host cells so it could be said they
| possess the other characteristics because they rely on the
| host cells for those as well.
| heavenlyblue wrote:
| Fire can also reproduce given a reasonable environment -
| would you call fire alive?
| throwaway15392 wrote:
| Personally I do
|
| So then that just means everything is alive
|
| Which I also agree with
|
| Energy is life. Life is energy.
|
| Subscribe for more very unorthodox HN comments
| samstave wrote:
| > __ _...looks more like a clever parasite hack_ __
|
| We call this "the federal reserve model" IRL
| SamBam wrote:
| I kind of agree. It also makes this statement a little
| confusing:
|
| > However, he believes "it's inevitable" that scientists will
| find more animals like Henneguya among those that have adapted
| to living in places with almost no oxygen, such as some parts
| of the ocean floor.
|
| The parasite can live because it's stealing ATP that's being
| made by an oxygen-burning organism it's attached to. How would
| you do that with no oxygen-burning organisms around?
| arkades wrote:
| The ocean floor has "almost no oxygen," not "no oxygen."
| There remain oxygen-burning creatures adapted to living
| beneath in hypoxic conditions.
| TheSpiceIsLife wrote:
| I dunno if _hypoxic_ is the right term here as it's usually
| taken to mean oxygen deprivation / insufficiency, which
| isn't what's happening here, as evidenced by organisms
| being adapted to the conditions.
| akiselev wrote:
| The oxygen concentration is actually quite a bit higher
| in most hadal zones (> 150 umol/kg [1]) than oxygen
| minimum zones that exist in the middle layers (< 45
| umol/kg [2]). It's definitely not a hypoxic environment
| relative to the rest of the ocean.
|
| [1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5829614/
|
| [2] https://web.stanford.edu/group/MicheliLab/pdf/oceanog
| raphica...
| tempestn wrote:
| I guess it could be like, in oxygen-poor places, animals are
| more likely to evolve to need less oxygen. Some (all that we
| know of so far) will do this by adapting to extract oxygen
| more efficiently and to use less energy, and others might do
| it like this parasite, by finding ways to extract energy
| directly from a host.
| SamBam wrote:
| It seems that it would still be surprising that such a
| parasitical organism could exist in such an environment.
|
| Presumably, if an organism is breathing in a near-zero
| oxygen environment, they are probably just getting the
| oxygen they need. If there's enough oxygen to support a
| parasite stealing from the first, there was enough oxygen
| to support the parasite getting its own oxygen.
|
| It seems to me much more likely that we'll find these
| parasites where there is plenty of oxygen:
|
| These organisms didn't evolve as a way of dealing with
| having no oxygen. They evolved because they adapted so that
| they did need to _bother_ with mitochondria, because there
| was a plentiful supply of ATP they could steal. Since they
| didn 't _need_ to burn oxygen, they could do without. And
| the environment they are in has so much oxygen that the
| host organism doesn 't suffer.
| LessDmesg wrote:
| There are whole different ways of life. For example, before the
| abundance of oxygen on Earth, the first bacteria lived on
| sulphur-based biochemistry. It was slow and inefficient, but
| better than being poisoned by that oxygen plague! Remember that
| it's an extremely destructive oxidizing agent (even in us it
| causes aging etc). It actually took millions of years for
| living organisms to start breathing oxygen (which was the real
| new and exciting breakthrough of the time).
| nobleach wrote:
| And this is why I argue when some refer to places like Saturn
| or Jupiter as "hostile toward life" or "Impossible living
| conditions". They are certainly hostile to they types of
| organisms with which we're familiar. But as we often find,
| nature has a way of surprising us.
| brabel wrote:
| It says only that this may be what they are doing, not that it
| is for sure... a little late they speculate other alternative
| as well: _Roger says animals can actually use an oxygen-free
| process to produce energy from sugar, but it's far less
| efficient. He suspects this may be what Henneguya is doing_
| hinkley wrote:
| > parasite
|
| Well now I don't want to look.
| loremdolorsipsi wrote:
| My fellow Wikipedia says Spinoloricus Cinziae was found first.
|
| Here's the source BBC article, from 2010:
| https://news.bbc.co.uk/2/hi/8609246.stm, the headline is "First
| oxygen-free animals found"
|
| https://en.wikipedia.org/wiki/Spinoloricus_cinziae
| atdrummond wrote:
| That would be one of the loricaferans mentioned in the original
| article.
| jshevek wrote:
| I'm not sure it's a valid claim, but the author implies there
| is a significant difference in the quality of the evidence:
|
| > _In fact, scientists have already proposed that one such
| group of animals called loriciferans can do that, and had some
| evidence that this was the case, although not as much or as
| detailed as for Henneguya._
|
| On the other hand, this might just be a justification for low
| key sensationalism.
| sabujp wrote:
| why can't they just say "first multi-cellular organism"
| [deleted]
| vanderZwan wrote:
| Based on the tone of the researchers giving comments on the
| results, this feels like a surprisingly uncontroversial discovery
| given how exciting it would appear to be, as if biologists with
| expertise in the domain were considering it to be possible but
| didn't have any examples of it until now. Is that a correct
| interpretation?
| ak217 wrote:
| The authors characterized an obligate parasite that lost its
| mitochondria and steals energy from the host instead. While
| this is technically the first animal to be found to lose its
| mitochondria, it's not the first eukaryote.
|
| They didn't find a novel eukaryotic energy system. There are
| many parasites that lose essential cellular machinery because
| the host provides it, this is just a relatively complex one.
| pvaldes wrote:
| The group is still poorly known and giving surprise after
| surprise in the last decades. Complex life cycle with two
| totally different kind of spores. Some were wrongly
| chategorised as two different species, other classified as
| animals are now known to be fungus (and two different
| lineages of very distant related fungus noneless)... Really
| misunderstood group for most of the modern scientific period.
|
| The idea that there was not one extant parasitic "jellyfish"
| [1] , but thousands of a new branch of parasitic cnidarians
| was revolucionary at 90's.
|
| [1] Technically they are not Scyphozoa, Cubozoa or Hydrozoa,
| so they are not jellyfishes (neither corals).
| dnautics wrote:
| Ok so to give you a bit of perspective, I didn't click through,
| and I thought, oh it's probably a parasite because parasites
| lose their mitochondria. Then I clicked through. I wasn't even
| a systems biologist, but a chemist/biochemist that got giardia
| once in grad school.
| pvaldes wrote:
| I had studied related species before, is a very strange group
| and economically surprisingly relevant.
|
| Is not clear if they looking at the plasmid or at the spore.
| Spores are made to endure harsh environments, "aren't totally
| alive" in a methabolic sense of the term, and could have
| created different methods to breath.
|
| Cnidarians are really old. From the article is possible that we
| could have a second lineage to mitocondrial origin, or that the
| animal have lost part of their DNA to simplify and adapt to
| parasitic life. Evolving to pack as many copies of itself as
| possible with minimum space and limited resources, and that
| would be really interesting, yes.
| TallGuyShort wrote:
| I think the key is this:
|
| >> Some microbes that don't breathe oxygen breathe hydrogen
| instead, but there's no evidence Henneguya does this. Some
| parasitic microbes don't breathe themselves, but steal energy
| molecules called ATP from their hosts. "We believe this is what
| our parasite is doing," Huchon said.
|
| This isn't an entirely novel thing they've discovered. Similar
| animal-like things have been studied, but this is the first
| time it's actually animal cells being observed with the
| behavior. It's something we've seen before, but only in even
| lower forms of life.
|
| It's cool and new interesting, but it's not paradigm-breaking.
| koeng wrote:
| Yep, that's correct. There are a lot of things that biologists
| tend to believe are out there, but are waiting for examples,
| which makes these kinds of discoveries very pleasant surprises.
|
| For example, it could kinda be assumed that we would find a
| phage that contained a CRISPR, and that turned out to be
| correct (it uses it to target other phages that infect the same
| host cell).
|
| Another fun example is a reverse-transcription based
| replicating plasmid found in a fungal mitochondria.
| Theoretically it was possible, but that madlad did it.
|
| A phage that I assume exists is one that replicates via
| reverse-transcription, but that hasn't been found yet. I hope
| they find it soon!
| itsgrimetime wrote:
| do you have links to reading about these? I'm curious but
| can't figure out search terms to find them myself
| ampdepolymerase wrote:
| Not to mention this sort of discoveries are so common now
| that it would be lucky to get a mention in top journals like
| Nature and Science at all. The incentives for biology is
| still deeply traditional; new, interesting, or novel
| discoveries do not necessarily get well rewarded at all. The
| biology research and development system strongly favors
| academia politics and close sourced large corporations.
| mekoka wrote:
| > The parasite doesn't appear to bother the fish much, she said,
| but tapioca disease can make its meat unmarketable and also cause
| the meat to spoil more quickly, making it a nuisance for the
| seafood industry: "No one wants to eat salmon full of white dots
| inside."
|
| In a sense this is, in fact, a symbiotic relationship. It's funny
| that we'd call it a disease, but this bug is a feature.
| oehtXRwMkIs wrote:
| Not really if you have to kill the fish to notice it has the
| parasite.
| whlr wrote:
| It can still work on a population level.
| pitiburi wrote:
| Well, you have to kill me to notice my liver, and still it's
| not a parasite.
| behnamoh wrote:
| It's not an _animal_ , the title is misleading.
| scribu wrote:
| What is it, then?
| empath75 wrote:
| why do you think it's not an animal.
| cambalache wrote:
| Because it is not bigger than a cat duh!
| pvaldes wrote:
| Henneguya are definitely metazoans, small and simple, but also
| very sophisticated ones.
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