Would Aliens be under the Kingdom Animalia?

[Blackhawk748]

Just what the title says. I was watching a Youtube video from a guy who is pretty good about zoology and he mentioned (rather offhand) that the animals of the planet in question shouldn't strictly be called animals, because that would be reserved for those found on Earth and since those aren't related in any form, they should have a different name.

I'm rather curious about this. Not just if its true, but what the hell we would call the new Kingdom to put them in. Xenos?

[Analytica]

Taxonomy like this generally depends on shared descent. Unless they are descended from Earth's initial life and more closely related to any metazoan than to any non-metazoan (e.g. plants or fungi), they are not animals in a taxonomic sense.

[Rakaydos]

Entirely different Tree of Life,means that aliens wouldnt be Animalia. You might still consider them Fauna, though.

[Asmotherion]

Unless some widely accepted as conspiracy theories turn out to be true that involve life on earth coming from some other planet there should be no relation to alien species and earth species; thus since no evolution co-relation would be traced between them there is no reason to classify them in the same group.

[InvisibleBison]

I would like to point out that, while taxonomically creatures from other planets wouldn't be animals, colloquially they absolutely would be. Etymology is not definition; there's no need to invent a new word for alien animals, just as you can call the shaking of the surface of any planet an earthquake.

[LibraryOgre]

I would like to point out that, while taxonomically creatures from other planets wouldn't be animals, colloquially they absolutely would be. Etymology is not definition; there's no need to invent a new word for alien animals, just as you can call the shaking of the surface of any planet an earthquake.

You might wind up with sciency folks calling them "pseudo-animals" or something similar. I've seen that at least a couple places.

[Tvtyrant]

We would probably add a new distinction level like astronomia, where pur Astronomia is Earth and theirs would be their planetary lineage. Then we would either use their taxonomy and terms of they have a sentient representative or make up new ones.

On a none-scientific level who knows what people would call them. I have known several people who used animals to exclusively mean cordates.

[gomipile]

Say that, eventually, more research was being done off Earth than on Earth, and also that there were some categories that were useful to use across trees of life of presumably separate descent. Given that, it would be reasonable to use the category name in general, and add descriptors for which tree of descent they were from if necessary. So, it might become useful to have a technical definition of "animal" and use that for all animals, and add a descriptor for origin if necessary. So, maybe Terra-animal vs Gummidgy-animal if the distinction mattered. Also possibly something like exo-animal for the category of all animals not descended from Earth's animals.

[veti]

I can see someone coining a word like "xenimal" to cover it, if it becomes an issue.

But I think the existing taxonomy of "kingdom" was devised on the assumption that only terrestrial life was being considered, and trying to expand it to include non-terrestrial life may well cause the whole idea to break down.

[Ravens_cry]

I'm going to go with 'no'. The whole point (well, one of them) of scientific names is to eliminate the 'cat' problem. No, don't worry, Whiskers and Mittens are safe, I mean how when people came to a new to them place, they would name the animals after other animals they were familiar with that looked vaguely similar. That's why you get so many different mammals with 'cat' in their common names, including Marsupials, who are about as far from a feline as you can get while still being a mammal.
So, no, they would not. We'd have to come up with a new term.

[Eldan]

It is, however, entirely common to have different scientific names and common use names for things. Scientific names have to be precise. Common use names have to be remembered by people. And then you get different naming in different disciplines. See the "Is tomato a fruit" argument. Botanically it's a fruit because it's a seed-bearing structure of a plant. Culinarily it's a vegetable, because it's a plant part we eat that is not sweet. Or see the word "Fish" for something more closely related to our "animal" problem here. What is a Fish? Well, taxonomically, there is no clade "fish". Because any clade that includes all fish also includes all land vertebrates. Scientifically, outside strict taxonomy,scientifically a fish is an aquatic craniate (a chordate with a skull of some kind) that has no digits on its limbs (and often also specifically exludes tetrapodes, the four-limbed animals). See how awkward that is? In common use, a fish is anything that looks like a fish to people. Historically, it's pretty much anything in the sea, see "crayfish", "cuttlefish" and "whalefish".

It would be the same with our alien animals. No, they would not scientifically be animals. Because while the definition of animal has characteristics like "breathes oxygen, can move in at least one stage of its life, consumes organic material, reproduces sexually", all of which may or may not be appropriate for our alien, it also includes things like "Is a eukaryote" and "is descended from the universal animal ancestor". Which our alien would not. So yes, they would be given a scientific name like "xenimals" or "pseudo-animals" as has been proposed here. Probably also an extra-formal scientific name, too, that is a bit more proper latin and will be forgotten e ven by most scientist. People will call them animals still.

What we would have then would scientificially be a "typological classificiation", as opposed to a "phylogenetic classification". I.e. a definition based on how something acts or looks, instead of what it is descended from. Science has decided to almost exclusively use the latter, but types do show up from time to time, in things like ecology. Definitions like "large predator" or "grazing herbivore" or "fish".

[jayem]

It is, however, entirely common to have different scientific names and common use names for things.

What we would have then would scientificially be a "typological classificiation", as opposed to a "phylogenetic classification". I.e. a definition based on how something acts or looks, instead of what it is descended from. Science has decided to almost exclusively use the latter, but types do show up from time to time, in things like ecology. Definitions like "large predator" or "grazing herbivore" or "fish".

I'm not too sure there's an exact definitional correspondence to something being in "Kingdom Animal" and being an Animal.
I suspect the typological classifications would (if more useful) dominate the use of "animal" even if we needed to rename the phylogenetic term.
While on the phylogenetic side, we'd need to do *gene-sequencing for what may be non-dna based *life and rapidly build a completely new set of trees (or take their word for it), and (unless we find a stargate) they won't fit in any of our categories.

I guess the key thing is do we [or advertisers] want to put "Xeno-mince" in with "Vegi-mince" or "Beef-mince"

[Eldan]

I'm not too sure there's an exact definitional correspondence to something being in "Kingdom Animal" and being an Animal.
I suspect the typological classifications would (if more useful) dominate the use of "animal" even if we needed to rename the phylogenetic term.
While on the phylogenetic side, we'd need to do *gene-sequencing for what may be non-dna based *life and rapidly build a completely new set of trees (or take their word for it), and (unless we find a stargate) they won't fit in any of our categories.

I guess the key thing is do we [or advertisers] want to put "Xeno-mince" in with "Vegi-mince" or "Beef-mince"

Oh, absolutely. 95% of every conversation in the world will talk about "animals". If we can eat them, they'll be meat. This entire discussion we are having here is nerd-stuff. It's all on the level of "Uhm, actually, bananas are herbs, not trees".

[veti]

See the "Is tomato a fruit" argument. Botanically it's a fruit because it's a seed-bearing structure of a plant.

What puzzles me is why it's always tomatoes. You can make exactly the same argument about cucumbers, capsicums, chillis, beans, even pumpkin, but nobody ever does. It's only tomatoes that the would-be pedants get excited about.

[Radar]

What puzzles me is why it's always tomatoes. You can make exactly the same argument about cucumbers, capsicums, chillis, beans, even pumpkin, but nobody ever does. It's only tomatoes that the would-be pedants get excited about.

Hard to say. Maybe it is that tomato is the most common of them all or it just got chosen at random for an example. There is also this.

[Lvl 2 Expert]

Wat everyone else says. They could be considered animals, because animals is a relatively vague term with no exact specific meaning. But they would definitely not be in the kingdom Animalia. That is, unless the idea of a kingdom is redefined, similar (but much more extreme) to how we have a class reptilia. If reptilia was a clade it would have to exclude crocodiles or include birds, so they invented a different way of grouping not based on common ancestry.

Depending on how alien life ends up looking and working and when and how much of it we discover we might start using terms like animal and reptile to describe any species from any ancestry with certain qualities (although I for one kind of hope there's more diversity to the universe than that). But they wouldn't fall under the Earths tree of life (although in the long run horizontal gene transfer could cloud even that discussion) and thus they would not fall under any earth kingdoms as we currently use the term.

[Wardog]

They could be considered animals, because animals is a relatively vague term with no exact specific meaning. But they would definitely not be in the kingdom Animalia.

I suppose it would be similar to how "carnivore" is used to mean both a) members of the order Carnivoria, and b) anything that eats mostly meat.

[Chronos]

Of course, we might well find aliens that resist fitting into our categories, even descriptively. Maybe there's a planet where all of the autotrophs are motile and all of the heterotrophs are sessile. Do we call the autotrophic ones "plants" and the heterotrophic ones "animals", or do we call the sessile ones "plants" and the motile ones "animals"? Better all around, there, to come up with new names for both.

[LibraryOgre]

I like the suggestion that we'd add another layer on top of Kingdom... Origin or something. So, the tardigrades spilled on the moon would, in a few centuries when they become adapted to the moon, would still fall under Earth origin, but the native creatures of Titan would fall under a different Origin. Under Origin, you might have "Pseudo-animalia" for things that look like animals, but you might also have "Wingslop" for motile autotrophs and their like.

[Bohandas]

You might wind up with sciency folks calling them "pseudo-animals" or something similar. I've seen that at least a couple places.

I would suggest "xenomal" as a term

I like the suggestion that we'd add another layer on top of Kingdom...

There's already two layers above kingdom. First are the "Three Domains" of Eukarya, True Bacteria/Eubacteria, and Archaebacteria. Above that is the division of prokaryotes vs eukaryotes

Of course, we might well find aliens that resist fitting into our categories, even descriptively. Maybe there's a planet where all of the autotrophs are motile and all of the heterotrophs are sessile. Do we call the autotrophic ones "plants" and the heterotrophic ones "animals", or do we call the sessile ones "plants" and the motile ones "animals"? Better all around, there, to come up with new names for both.

I was about to say something like this but you beat me to it (although my version was going to reference fungus-like creatures instead)

Wat everyone else says. They could be considered animals, because animals is a relatively vague term with no exact specific meaning. But they would definitely not be in the kingdom Animalia. That is, unless the idea of a kingdom is redefined, similar (but much more extreme) to how we have a class reptilia. If reptilia was a clade it would have to exclude crocodiles or include birds, so they invented a different way of grouping not based on common ancestry.

It's still a valid clade because reptilia and aves aren't polyphyletic. It simply isn't practicable for the scientific name of every species to read like the passage in [redacted] where they spend half a chapter just listing the genealogy of [redacted]

I suppose it would be similar to how "carnivore" is used to mean both a) members of the order Carnivoria, and b) anything that eats mostly meat.

Or how "bug" can mean anything from just insects to just a specific type of insect to any arthropod to any organism that's small and unwanted or gross and isn't a tetrapod

[Mechalich]

I like the suggestion that we'd add another layer on top of Kingdom... Origin or something. So, the tardigrades spilled on the moon would, in a few centuries when they become adapted to the moon, would still fall under Earth origin, but the native creatures of Titan would fall under a different Origin. Under Origin, you might have "Pseudo-animalia" for things that look like animals, but you might also have "Wingslop" for motile autotrophs and their like.

It's not a matter of layers, but of alternate Trees.

Everything on Earth alive today and that we know of from the past is part of a single tree of life, one that stretches back to LUCA - the Last Universal Common Ancestor - which is the surviving population from a slew of early proto-microbes that all later life descended from and serves as the ultimate root to all phylogenetic trees for Earth lifeforms.

Ecosystems on other worlds would have emerged following seperate abiogenesis events to that of Earth's and therefore have their own versions of Luca on completely separate trees from our own. So you'd have the Earth Phylogentic tree, separate from the phylogentic tree of the Barnard's star or Tau Ceti, or wherever you found life and while convergent evolution might result in groups on those trees that resembled animals, they would be completely different things. So science would probably talk about the 'Terran Tree' and the 'Cetian Tree' or something like that.

Note that life from an alternative abiogenetic event would probably be very different from Earth-based life at the chemical level. RNA, for example, has 16 possible stereoisomers, but all life on Earth uses the same one. Likewise all Earth-based life uses the same 22 amino acids, even though we know of at least 500 that exist naturally. As a result, alternate trees should be fairly easy to differentiate even if they produce Earth-like carbon based life with the same kind of basic molecules.

[Berserk Mecha]

Don't the xenomorph embryos absorb parts of their host's DNA into their own DNA to better adapt to their host's environment? Wasn't that supposed to explain how the runner from Alien 3 looked and moved differently from the other aliens? (Because it came from a dog or a cow, depending on which cut of Alien 3 one watches.) If so, that really muddies the issue. Having an organism that is breed from two separate organisms with completely different origins would seriously have biologists reconsider how the tree of life is organized.

[Radar]

Don't the xenomorph embryos absorb parts of their host's DNA into their own DNA to better adapt to their host's environment? Wasn't that supposed to explain how the runner from Alien 3 looked and moved differently from the other aliens? (Because it came from a dog or a cow, depending on which cut of Alien 3 one watches.) If so, that really muddies the issue. Having an organism that is breed from two separate organisms with completely different origins would seriously have biologists reconsider how the tree of life is organized.

Truth be told, in terms of biology Alien just cannot work in any concievable way. For this kind of DNA splicing you would first have to assume that Aliens, Predators and all life on Earth has the same origin. Considering Prometheus it might be true frankly but then there is another problem of exceedingly acidic blood of the xenomorphs, so their biochemistry is completly incompatible with ours.

Nevertheless, I think the topic is more about general case of aliens and not the particular Alien.

[Eldan]

That idea would really work a lot better if instead of being chest-bursters, the facehuggers just kind of fused with their hosts, took over the brains and mrophed the body into an alien. But I think monster transformation has been done too often in SciFi before.

[sktarq]

With the rise of the cladistic models in particular (congrats you are a vertebrae, a fish, an amphibian, an amniote, and a mammal (I could go on but frankly)) that would be "meh"...it would probably still be an "animal" (because cat issues above and does it consume other life forms for nutrition questions) but not a member of the Kingdom Animalia which is the modern scientific definition of an animal.

Don't the xenomorph embryos absorb parts of their host's DNA into their own DNA to better adapt to their host's environment? Wasn't that supposed to explain how the runner from Alien 3 looked and moved differently from the other aliens? (Because it came from a dog or a cow, depending on which cut of Alien 3 one watches.) If so, that really muddies the issue. Having an organism that is breed from two separate organisms with completely different origins would seriously have biologists reconsider how the tree of life is organized.

In theory yes...they even made a whole line of toys based on the idea....The bull alien toy had lyre pattern bulls horns IIRC...it was supposed to make sense in terms of xenomorphs being the "ultimate killers" type in terms of being able to adapt to any local environment....at least thats what the minicomics that came with said toys blathered on about....then again I could swear their were four armed purple apes (which seems a total rip of the four armed white apes of ERB Barsoom even to ten year old me) that did not lead to four armed xenomorphs so I'm not expert in this particular lore.
myself I just never figured out where it got the food to grow so damn fast, especially since humans are not great sources of the "polarized silicon" that apparently their exoskeletons are made with (source Ash...thus unreliable)

[Bohandas]

That idea would really work a lot better if instead of being chest-bursters, the facehuggers just kind of fused with their hosts, took over the brains and mrophed the body into an alien. But I think monster transformation has been done too often in SciFi before.

Isn't that just the headcrabs from Half-Life?

[Eldan]

I suppose it is.

[hamishspence]

Mind flayer ceremorphosis works a similar way - tadpole inserted into head of victim, morphs victim into mind flayer.

[Beleriphon]

You might wind up with sciency folks calling them "pseudo-animals" or something similar. I've seen that at least a couple places.

Xeno-animals seems a likely name. That said at the most basic level the tree of life starts with "Life" as very first level, and branches from there. So we could indeed a have a xenobiological creature in our tree of life, it would just be a different root rather than a completely different tree.

[Squire Doodad]

Xeno-animals seems a likely name. That said at the most basic level the tree of life starts with "Life" as very first level, and branches from there. So we could indeed a have a xenobiological creature in our tree of life, it would just be a different root rather than a completely different tree.

Or, if you want to get more sciencey, Xenofauna.

I would say that xenobiology would belong to a different tree. The tree of life is things that stem from a single (or incredibly close groups) of life, and alien life would simply not be connected to it at any point. An alien life form that does horrifying Alien stuff could have the Earthling "morph" be considered to be on the tree, but the original species itself would not.