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MarqFJA The Cosmopolitan Fictioneer from Deserts of the Middle East (Before Recorded History) Relationship Status: Anime is my true love
The Cosmopolitan Fictioneer
#1701: May 19th 2023 at 7:44:52 AM

In some fictional settings, an organism is physically transformed so radically that, had they been encountered by a hypothetical biologist who is unaware of both their original nature and the fact that they've been transformed, the biologist would be forgiven for classifying the organism as an entirely different species. The methods vary a lot, from "scientific" ones like genome-level biological modification, to straight-up magic (somewhere in there lies transformation induced by entities that are above and beyond the physical laws of our reality).

Suppose that such a hypothetical biologist learns all those facts. Realistically speaking, would the discovery that an organism's species can be effectively "changed" upend what had been the standard paradigm for biological classification? Or would it just lead to such transformations be considered as an "inflicted abnormality" or somesuch, loosely similar to developmental disorders?

What if a particular kind of transformation results in each subject sharing the same biological "template", and collectively they prove to be capable of biological reproduction to create more individuals of that same template?

Edited by MarqFJA on May 19th 2023 at 5:45:01 PM

Fiat iustitia, et pereat mundus.
DeMarquis (4 Score & 7 Years Ago)
#1702: May 19th 2023 at 8:50:11 AM

Microbiology tells no lies. If their DNA can be examined, that should settle the question of who derived from whom, and how.

All bets are off if magic is involved, of course.

I'm done trying to sound smart. "Clear" is the new smart.
Eriorguez Since: Jun, 2009
#1703: May 19th 2023 at 8:54:58 AM

HeLa cells are unicellular organisms able to grow in lab cultures. They also started as human cells.

Contagious cancers, such as the Tasmanian devil and dog ones are technically Tasmanian devils or dogs turned into pathogens.

alekos23 Since: Mar, 2013
#1704: May 19th 2023 at 9:12:20 AM

Then there's the hypotheses about what the viruses started out as I guess? If they even count as alive anyway.

Eriorguez Since: Jun, 2009
#1705: May 19th 2023 at 9:30:38 AM

Yeah, parasites evolve after their hosts.

SeptimusHeap from Switzerland (Edited uphill both ways) Relationship Status: Mu
#1706: May 19th 2023 at 9:34:54 AM

Regarding to viruses, retroviruses clearly evolved from pieces of mobile DNA. Others (giant viruses like mimivirus?) might have evolved from protozoans. Or not. I don't think this is a well-studied field.

"For a successful technology, reality must take precedence over public relations, for Nature cannot be fooled." - Richard Feynman
MarqFJA The Cosmopolitan Fictioneer from Deserts of the Middle East (Before Recorded History) Relationship Status: Anime is my true love
The Cosmopolitan Fictioneer
#1707: May 19th 2023 at 5:17:35 PM

Microbiology tells no lies. If their DNA can be examined, that should settle the question of who derived from whom, and how.
Yeah, but what if the alterations reached all the way to the genetic level, and were so drastic that even examining the genome would lead you to believe that this a whole different species? After all, the best way to make radical modifications to an organism's macroscopic morphology and physiology endure in the long term is to enact them on the genetic level across the organism's entire body.

Edited by MarqFJA on May 19th 2023 at 3:21:13 PM

Fiat iustitia, et pereat mundus.
DeMarquis (4 Score & 7 Years Ago)
#1708: May 19th 2023 at 7:32:09 PM

Well, I suppose that if you are changing the DNA so much that all connection to the parent species has been erased, then effectively you are starting over with an entirely new form of animal. It's like saying you've taken bits and pieces of a computer program, entirely reordered it until it does something unrelated to what the first program did. There really is no connection anymore.

I'm done trying to sound smart. "Clear" is the new smart.
MarqFJA The Cosmopolitan Fictioneer from Deserts of the Middle East (Before Recorded History) Relationship Status: Anime is my true love
The Cosmopolitan Fictioneer
#1709: May 20th 2023 at 1:28:39 AM

I was more thinking like, say, subjecting an adult human to real-time genomic modification note  with both wolf genes and custom-designed genes so that the end result is essentially a werewolf.

Sure, analyzing the genome could show that it logically must have used a human genome as the base, but if the final genome deviates significantly from the human one (e.g. it has a different number of chromosomes), then... what? Does it still count as Homo sapiens?

And suppose that a number of these gengineered werewolves were created, and proved to not only be able to reproduce but the offspring are always werewolves of the same general template, while interbreeding with humans either fails outright or produces sterile hybrids of generally inconsistent "template" (that is, comparable to how you get a tigon or a liger depending on the sexes of the lion and tiger parents). What does that say about them?

Edited by MarqFJA on May 20th 2023 at 11:38:54 AM

Fiat iustitia, et pereat mundus.
Bexlerfu Khatun of the Azim Steppe from Mol Iloh Since: Nov, 2020
Khatun of the Azim Steppe
#1710: May 20th 2023 at 1:48:50 AM

Contagious cancers, such as the Tasmanian devil and dog ones are technically Tasmanian devils or dogs turned into pathogens.

In a very loose sense. The DFTD is not significantly different from cancers in other organisms, it just happened to proliferate in a population with extremely limited genetic diversity, leading to MHC being unable to identify them as external.

By that definition, human cancers are pathogens that have exactly one host.

Then there's the hypotheses about what the viruses started out as I guess? If they even count as alive anyway.

They do not, and neither do prions. As for their origins, Dawkins hypothesized in The Selfish Gene that they might be the ancestors of all life as we define it, as the first nucleic acid replicating systems - but that is more of a provoking thought than a real proven theory.

Yeah, but what if the alterations reached all the way to the genetic level, and were so drastic that even examining the genome would lead you to believe that this a whole different species? After all, the best way to make radical modifications to an organism's macroscopic morphology and physiology endure in the long term is to enact them on the genetic level across the organism's entire body.

That's basically a major plot point in Mass Effect 2. You would still identify parenthood, even if you tremendously sped up the mutation process. The only way to create a "whole different species" would be to build it literally from scratch, creating life like Doctor Manhattan. If you use any kind of blueprint that functions with DNA-RNA-Proteins for your new species, it will be possible to see which organism you started from thanks to its highly-preserved DNA/RNA sequences.

Sure, analyzing the genome could show that it logically must have used a human genome as the base, but if the final genome deviates significantly from the human one (e.g. it has a different number of chromosomes), then... what? Does it still count as Homo sapiens?

Hybrids exist in real life. If two of your werewolves can reproduce over more than two generations without outbreeding depression, then they can qualify as a species. Although if they can breed with wolves and/or humans and have fertile kids, they might merely be subspecies.

Edited by Bexlerfu on May 20th 2023 at 11:01:42 AM

Eriorguez Since: Jun, 2009
#1711: May 20th 2023 at 4:48:11 AM

There are plenty of contagious cancers, not just devil face tumors. Hell, a contagious leukemia equivalent is widespread among bivalves. It works like a pathogen, and it thrives as that, outliving the original organism (unlike regular cancers, which are dead ends).

The Selfish Gene is a book from nearly 50 years ago as well. Consensus is heavily on the side of viruses NOT being ancestral. And same deal with the Mayr definition of species, a quite flawed one; equids are weirdos and do not make good models for interspecific hybrids (and it also makes asexual individuals each a single species, as they cannot crossbreed by definition). We have enough species complexes to understand that "if hybrid is fertile they are the same species" is a BAD metric.

Anyway, dropping a neat talk by Thomas Holtz on current Tyrannosaurus biology, neat stuff to listen to while doing chores or the like, as guy is always a pleasure to listen to:

Edited by Eriorguez on May 20th 2023 at 1:49:13 PM

MarqFJA The Cosmopolitan Fictioneer from Deserts of the Middle East (Before Recorded History) Relationship Status: Anime is my true love
The Cosmopolitan Fictioneer
#1712: May 20th 2023 at 9:11:32 AM

If two of your werewolves can reproduce over more than two generations without outbreeding depression, then they can qualify as a species.

That's what I was thinking. I suppose the taxonomic placement of this species would be a subject of debate over whether such artificially modification should be given equal treatment to natural evolution, determining what existing species is the direct ancestor, and such.

Although if they can breed with wolves and/or humans and have fertile kids, they might merely be subspecies.

Dogs and wolves can and do produce fertile hybrids, and they're argued to be separate species under the Evolutionary Species Concept (as opposed to the Biological Species Concept) on account of dogs having gone down a separate evolutionary path. And there are the naturally occurring hybrids of grizzly and polar bears (Ursus arctos and Ursus maritimus respectively), which have proven fertile.

It would definitely be headache-inducing, however, if these werewolves somehow prove able to interbreed with and produce fertile offspring from both wolves and humans. The distance between these two mammalian branches is not trivial.

Fiat iustitia, et pereat mundus.
Bexlerfu Khatun of the Azim Steppe from Mol Iloh Since: Nov, 2020
Khatun of the Azim Steppe
#1713: May 20th 2023 at 8:13:44 PM

There are plenty of contagious cancers, not just devil face tumors. Hell, a contagious leukemia equivalent is widespread among bivalves. It works like a pathogen, and it thrives as that, outliving the original organism (unlike regular cancers, which are dead ends).

So, a very quick google search nets the following quote...

So far researchers have only identified three transmissible cancers.

https://frontlinegenomics.com/transmissible-cancers/

...with two occurring in animal populations whose genetics have not evolved only through natural processes. So "plenty" is a bit of a stretch.

Plus cancer cells are always pathogens in the sense that they cause diseases. They're just non-transmissible pathogens, like auto-immune antibodies.

Dogs and wolves can and do produce fertile hybrids, and they're argued to be separate species under the Evolutionary Species Concept (as opposed to the Biological Species Concept) on account of dogs having gone down a separate evolutionary path. And there are the naturally occurring hybrids of grizzly and polar bears (Ursus arctos and Ursus maritimus respectively), which have proven fertile.

The problem for me is that those two concepts are used to produce a metric shit-ton of frankly dispensable scientific articles that aim at discovering new species, like everything regarding the one/two species of African elephant. Which is why I tend to ignore it as much as I can; if you were to have those kinds of interrogations to write some sci-fi, it would be way more relevant to discuss populations, not species.

Edited by Bexlerfu on May 20th 2023 at 5:21:35 PM

MarqFJA The Cosmopolitan Fictioneer from Deserts of the Middle East (Before Recorded History) Relationship Status: Anime is my true love
The Cosmopolitan Fictioneer
#1715: May 31st 2023 at 12:35:47 AM

I'm designing a fictional human-derived species with five separate sexes: male, female, androgynous hermaphroditenote , andromorphic hermaphroditenote , and gynomorphic hermaphroditenote . My main problem is coming up with a variation on the XY sex determination system that adds a third chromosome tied to the hermaphrodite sexes, and make any possible pairing capable of producing any of the five sexes.

Try as I might, though, I couldn't figure out a solution. At this point, I'm sorely tempted to invoke Artistic License and just do the following:

  • There are a pair of sex chromosomes: The first is neutral with respect to sex determination, and is shared by all individuals; the second has a specific genetic locus on it with three different alleles that determines whether the individual will be male, female or hermaphroditic, and another locus that determines which of the three hermaphrodite sexes manifests (which is only relevant if the hermaphrodite allele of the sex locus is present, otherwise it becomes inactive).
  • When a gamete is produced, each of the two loci's allele can be changed to a different one during meiosis, meaning that no matter the sexes of the reproducing individuals, their offspring can be of any of the five sexes. In other words, it's like the second chromosome can act as one of five different sex chromosomes (dubbed "V", "W", "X", "Y", "Z").

How plausible is this? Personally, this seems like soft sci-fi, but it did happen in the past that I independently thought of an idea that I believed to be purely fictional, only to later discover that it has happened in nature.

Fiat iustitia, et pereat mundus.
Florien The They who said it from statistically, slightly right behind you. Since: Aug, 2019
The They who said it
#1716: May 31st 2023 at 12:58:18 AM

Lots of species have a bunch of sexes. Nearly all of them are fungi though, or small eukaryotes. They're called mating types and they're thought to be the ancestor to modern sexes. They don't use chromosomes though because that's a lot of extra energy for such small things, but using a mating-type locus (that's how they determine development patterns instead of chromosomes) but generalized to an animal could get you the effects you want, if you don't want to hand wave it.

But if you want to know more about things that have a bunch of mating types, look into fungal reproduction. Fungi in particular have a lot going on reproductively speaking.

Edited by Florien on May 31st 2023 at 12:59:06 PM

MarqFJA The Cosmopolitan Fictioneer from Deserts of the Middle East (Before Recorded History) Relationship Status: Anime is my true love
The Cosmopolitan Fictioneer
#1717: May 31st 2023 at 5:32:09 AM

Oh hey, the protozoan Tetrahymena thermophila has something similar, having seven "sexes"/mating types, and it kinda has that "offspring sex is not limited by the sexes of the parents" aspect that I want. It can do this because it has two nuclei in its cells: A somatic nucleus, which holds the organism's "working copy" of the genome (i.e. what it uses to govern its physiological processes, like the singular genome in most other organisms like us), which only has the genes for one mating type; and a germline nucleus, which is exclusively for reproductive purposes, and whose genome contains the genes for all the mating types. After the newly made offspring inherits the germline genome and begins to form its own somatic nucleus, it takes a copy of the germline genome and then more or less randomly eliminates the mating type genes in said copy until only one remains, leaving the germline nucleus untouched.

In other words, my suggested approach is surprisingly realistic, I just need to tweak the idea by involving the double nucleus element.

Edited by MarqFJA on May 31st 2023 at 3:32:39 PM

Fiat iustitia, et pereat mundus.
SeptimusHeap from Switzerland (Edited uphill both ways) Relationship Status: Mu
#1718: Jun 12th 2023 at 8:32:38 AM

Enquiring minds would like to know why your cell would keep two nuclei in its body. I'd expect that if your species has two nuclei in its germ cells, its non-germ cells would eliminate the germline nucleus. I also think that having so many genders might make reproduction extremely difficult.

Trees are much more common in deserts than people think; in super-dry parts of the Sahara there is on average 70 trees per square kilometre, but they are isolated instead of forming forests.

"For a successful technology, reality must take precedence over public relations, for Nature cannot be fooled." - Richard Feynman
Bexlerfu Khatun of the Azim Steppe from Mol Iloh Since: Nov, 2020
Khatun of the Azim Steppe
#1720: Jun 15th 2023 at 2:17:43 AM

Regarding the question asked above regarding five-gendered species, it could work with a triple sexual chromosome system, and 4 different chromosomes. I'll use XYAB but any letter works.

The basic rule is that you will have two types of gametes, 1 and 2. Gametes 1 will have 1 sexual chromosome, gametes 2 will have two, and there can only be a fecondation between 1 and 2.

As far as genders go, X and Y will be the classical gender chromosomes : if you have two you are male or female. A is the female-coded herm chromosome and B is the male-coded one: if you have two you are herm.

During meiosis gametes 2 will get 1 chromosome of each category, and gametes 1 will get whatever remains. So you will always have individuals with at least one chromosome of each category. No XXX or AAB. However that means two herms will have a herm - you can remove the rule and say some egg cells are non viable, in which case anyone can have anything on paper.

So basically...

  • XXA, XXB, XYA: female
  • XYB, YYA, YYB: male
  • XAA, YAA: gyn herm
  • XBB, YBB: andro herm
  • XAB, YAB: androgynous herm

Edited by Bexlerfu on Jun 15th 2023 at 11:22:14 AM

Redmess Redmess from Netherlands Since: Feb, 2014
Redmess
#1721: Jun 15th 2023 at 3:07:23 AM

Alternatively, you could add another chromosome into the mix, like X, Y, and Z, which gives you six combinations, XX, XY, XZ, YY, YZ, and ZZ while still working with basically terrestrial DNA.

You could come up with any number of reasons why one of those six doesn't show up. Maybe two of the genes don't mix well, or maybe one combination is naturally or artificially suppressed somehow.

Hope shines brightest in the darkest times
dRoy Professional Writer & Amateur Scholar from Most likely from my study Since: May, 2010 Relationship Status: I'm just high on the world
Professional Writer & Amateur Scholar
#1722: Jun 26th 2023 at 7:25:49 PM

There are very few movies that actually make me rethink the way I view the world...and of all movies, Nope by Jordan Peele became one.

The film's main theme is the danger of anthropomorphizing wild animals and that human should keep proper respect and boundaries around them, which was conveyed through a chimpanzee massacre and a carnivore alien (long story).

And I must confess, I did fall into the whole All Animals Are Dogs mindset from time to time, even though how misleading and outright dangerous it can be.

Edited by dRoy on Jun 26th 2023 at 11:25:58 PM

Continuously reading, studying, and (hopefully) growing.
Kaiseror Since: Jul, 2016
#1723: Jun 26th 2023 at 7:35:18 PM

[up] One (probably nitpicky) criticism I had with the film was the assertion that all wild animals react violently to eye contact. Jean Jacket eats people when they look at it, but with predatory animals, avoiding eye contact is one of the worst things you can do. Ambush predators like big cats won't strike if they know you can see them, while pursuit predators like wolves or hyenas are more cautious with prey that's staring them down instead of running away. Eye contact provoking aggression is usually more of a territorial response (which they did get right with Jordy).

dRoy Professional Writer & Amateur Scholar from Most likely from my study Since: May, 2010 Relationship Status: I'm just high on the world
Professional Writer & Amateur Scholar
#1724: Jun 26th 2023 at 7:40:27 PM

I don't think the film applied that to ALL predators and made Jean Jacket only analogous to the likes of chimpanzee, thus the whole sub story-line about Gordy. It was also heavily implied, if not outright stated, that Jean Jacket IS a territorial predator.

Continuously reading, studying, and (hopefully) growing.
Kaiseror Since: Jul, 2016
#1725: Jun 26th 2023 at 8:03:59 PM

[up] My assertion is that if Jean Jacket is a predator (which it is) then its response to eye contact would prevent an attack rather than start on. Predators don't respond to challengers by trying to eat them.


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