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3:54 PM
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A: Why would a species of intelligent parthenogenetics invent males?

dsollenthese premises are hard to work with, which is not a complaint about the question exactly. I think that there is allot of interesting things that could come out of this question, but without more back-and-forth discussion it's hard to know where to focus my answers. I will therefore try to do t...

 
I think it's great that you pointed out the flaws in my suggestion. However, your model is problematic, because it assumes a constant genetic difference between each generation. If any gene can successfully mutate, then the extreme divergence that you predict will occur. But even in bacteria, even in situations with minimal gene transfer, it does not, because a large percentage of the genes are nearly essential. There will be heavy variations in hair color, or toenail growth rate, or whatever, but too many genes are essential for there to be 50% divergence after 30 generations.
The problem is this. A 2% genetic difference is already all that separates humans from chimpanzees. So by mutating 2% of the genes, you can go from humans to chimpanzees. But it has to be exactly the right 2%! The low odds of the right 2% of genes mutating is precisely why a 1% difference each generation doesn't work. With any finite, compounding difference, eventually we get to a point when most combinations of mutations are simply fatal. Even bacteria have this problem.
What might happen is this: the unessential genes, specifically the same ones that vary frequently in humans (which is much less than 1 percent) would occasionally mutate the first generation. But the next generation, the SAME genes would mutate, not additional ones. This would be selected for by evolution, because Parthans with frequent mutations in the same sorts of genes that cause variations in humans would be more fit than both Parthans with little variation (because they could not adapt) and Parthans with variation everywhere (because even the best error-checking could not keep up).
 
Jonah, I agree...and disagree with you. I had throught of the same issue, didn't address it due to the answer already being too long. For mutation to actually lead to adaptation the mutation can not be exclusilvy limited to 'safe' genes, it must include more life-critical genes. Some 'safer' genes may be adpated to be more prone to mutate, but all genes must be on the potential chopping block or you don't change species. It's those mutations that are random, and unlikely to mutate back due to the pure size of genome relative to the one tiny gene that's it's unlikely it will mutate ...
@Jonah ...again that will lead to the more interesting specization, Most likely many of the species on the world are 'primative' Pathons that didn't get one mother's species-changing mutation. Over thousands of generations of evolution this would lead to an oddly haphazard mixture of Pathons of varying similarity genetically. Keep in mind the 'race wars' issue is also a major one, they will be evolved to recognize similar genetics and attack those that don't meet it as consuming resources that their genetically identical (nearly) children need.
 
dsollen, I understand what you are saying. Of course all genes are "on the chopping block," as you say. That is merely a consequence of the many mutagens that any species encounters! There is no perfect error correction. I am not concerned with speciation, but with diversity within the species. As you note, some "safe" genes may be more prone to mutate.
Your are correct that there could be a mixture of Parthans of varying species. But not necessarily. What if all the Parthans are descending from a few primogenitors who possessed certain species defining genes? And what if, at some point, there were very strong selection pressures that heavily favored certain genes? Example: 100,000 years ago, we had 1000 distinct Parthan lines, all with adaptions ideal for different environments. One line had extremely high radiation resistance. There was then a sudden increase in radiation (ozone layer destroyed?). Those Parthans alone survived.
Also, the speculation about a race war seems a little curious to me. There would be wars, certainly. But one need not be very genetically distinct from someone before a war is efficient. I would hardly think that the additional genetic difference would lead to more wars than among humans. In any case, those wars, if they existed, could be in the past, with civilization having decreased their frequency. More to the point, there is actually more genetic similarity between Parthans, assuming moderate unessential gene mutation, than between human parents and their children. They might be closer.
 
@Jonah, I would love to discuss this, because I do find it interesting. But comments aren't a good source for it. If you want to spawn a chat instead we can hammer it out there. To address your second comment I would say that 'race wars' is the best explination for why the species isn't as diverse as it could be, that Pathans that are similar but with key distinguishing traits from a major mutation (not a safe one) tend to end up in a war with the others due to biological programmed competitiveness, the deviants are usually destroyed. Still, a depressing species to build culture for.
The race war issue is due to how genetically similar everyone is, it's sort of hard for me to explain... In worlds with sexual reproduction everyone, even your immediate family, is very different from you. Therefore fighting someone over small differences is silly. Despite this, it's been proven that we are biologically programed to distrust others that are more genetically different then us, and much of our racism of today comes down to that biological imperative.
 
I understand that race wars could provide a control mechanism for speciation mutations. I still prefer the explanation that some cataclysmic event selected one line at some point in the distant past. In combination with high rates of safe mutations, this gives us:
 
3:57 PM
Altruisum is more common with those who are known to be genetically similar, but also more common with those that simply look more similar. We instinctually are more trusting and work better with those that appear to have shared genetics with us (which doesn't make it right of course, racism is still horrible).
 
1) A society with relatively high diversity, where parents are children are at least difference
2) A plausible mechanism by which a single species could emerge
and 3) no nasty race wars and other cultural issues
 
but if everyone is identically genetically, or close to it, then the distinction between "share my genetis" and "doesn't" is more exact. Even one major mutation means someone who is 'not one of us'. Because there is so little genetic diversity this tendency would be greatly elivated because it's easier to distinguish. Also, today tendency are mitigated by other biological impreatives to avoid inbreeding and thus encourage some level of interaction with other's of different genetics
 
There will not be low genetic diversity, though! The mutation rate can be set wherever you want it to be.
 
yes, I figured you wouldn't like that outcome, I don't either. It sucks when evolution does nasty things ;). The best mechanism to avoid it is to have some from of genetics shared, even if you don't have males
I would look into other gene sharing mechnaisms. these would keep the race from diverging as much, incourage more coperation, and could justify mates and romance which you seemed to want.
 
You do NOT need that! That's what I have been saying! Simply set the mutation rate on safe loci to approximate the genetic difference between human parents and their children.
Which I seemed to want? The OP wanted romance. I don't care.
 
4:01 PM
There is a certain minimum mutation rate required to justify sentience. That's the problem with a lack of genetic sharing, it's very hard for complex species to evolve. You need a (reatlivey) very high mutation rate to make up for it.
oh sorry, yes the OP not you ;)
 
Is it very hard? Or is simply a matter of the wrong selection pressures?
Just because something is not seen on Earth, does not mean there might not be an environment in which it is favored.
 
besides, however high or low the mutation rate is, the fact is if you went from non-sentient to sentient in X time period through only minor mutation passed on to children your get a huge diverse swath of species, all slightly different. The distinction of 'species' is blurred and unidentifiable. This one has 90% of your genetics, that one 92%, that one 80. It's just lots of semi-similar creatures of varying genetic difference.
the problem is one of competition.
say you have paton X, or magically developed sentience.
she can survive to adult hood, and have children perhaps.
 
I don't care about the diversity of species. I already came up with a solution to that.
 
but if she can't mate her genes don't spread as fast, and there are millions of others without sentience she is compeeting with
even if sentience is beneficial, the statistical odds are she will die out before her young spread out enough to have a strong 'hold' on the world.
basically, benficial traits have a much harder time surviving and spreading because they can not be shared across other young, and odds are they just die out even if benefical. Studies show pathnogenic species tend to have very little growth and mostly stagnate genetically.
 
Hmmm
 
4:06 PM
Plus, sapience specifically only works within a community
you need OTHER sentient beings to really benefit from it
 
Sapience only works in a community?
How sapient are we talking here?
 
communication
 
Bears, spiders, other habitually solitary creatures
 
that at least requires a community. Studies suggest (though by no means is it definitive) that the begining of communication is what lead to nearl all other sapience.
they don't have communication, or at least not the nuianced kind that language provides.
and for language to develop you need others to share it.
your immediate family would in a pathnogenic society, but the other 99% of the world wouldn't
which means adaptations towards communication would have less advantage. Why pay the added cost (brain power required for complex lanauge means high caloric intake) if it only benefits a few.
 
Right then. What we need is a fairly unlikely mutation: linguistic communication in combination with the radiation resistance mentioned earlier.
Think that would work?
 
4:10 PM
it could happen still, I could hypothesis ways to make it happen. However, it's less likely. combined with how stagnent creatures without sex are genetically...it grows rather unlikely they would not only evlove, but evolve in such an implausable way.
well, the best justification would be linguistic communication started as a way to work within the family, to out compete other non-family members
and that they did just that, which is why non-sapient versions of patnos don't really exist.
 
Well, fine. There you go, you found a justification for the development of intelligence, without recourse to large communities.
 
it's still unlikely, very much so, without an external form of increased mutation.
 
Well, high radiation.
 
to justify how such improbably mutations happen from a species that is prone to genetic stagnation.
 
Perhaps it waxes and wanes
This seems like a better solution by the minute
 
4:13 PM
the process of developing sapience would take an extremly long time.
 
That's what geological time is for.
 
a simple wax & wane of mutigens wouldn't be enough. you would have to have a MAJOR world changing situation to effect mutation sources if you want to remove a mutagen that has been around that long
and major world changing events tend to kill of the creatures with least genetic diversity....
 
Remove a mutagen? Why?
 
why would a mutagen exist for hundreds of thousands of years and then just stop?
 
It would not. My hypothesis is that a Parthan evolves an extreme degree of radiation resistance, around the time that a huge influx of radiation comes from some source. Only this line survives.
 
4:16 PM
if that radiation is what causes sapience to evolve
then that radiation has to exist for a gelogical time period.
 
Of course. But then it becomes even higher.
One level of radiation to cause evolution. Another to create a single species
 
if anything I would go the other route. whatever REMOVED the mutagen wiped out the rest of the species.
they evolved to a world where they expected it. the world-changing event that causes the mutagen to become less common was enough to kill off most of the species in the world. only the ones that were sapient were able to survive it.
 
That could work. I prefer the background of a planet with high levels of radiation, and frequently oscillating levels at that. It provides some good possibilities for future cataclysms.
 
because again, a pathnogenetic species does not handle world changing events at all well; it's their biggest weakness. You can't easily hypothesis changes to enviroment because most changes will kill them.
 
They would. But my specific hypothesized change would not.
 
4:19 PM
they couldn't survive frequent oscillation!
 
Depends on the time scale.
 
each osilation would be a near-extinction for them.
 
yes, exactly
Thus the emergence of the modern Parthan race.
However, future events could be more problematic
However, given that they have evolved sapience and developed space travel at this point, that does not seem to be a big problem.
 
okay...it's better. I still think it's rather implasable just due to how genetically stagnant pathenogensis is, but writers get some artistic license.
there is still an issue though.
 
what would that be
 
4:22 PM
how many generations since the last radiation oscillation?
it would be implausable that this species would exist and others that hared 90
 
sorry
what?
 
*99.95% of their genetics didn't
hit enter too soon ;)
so your still get the near-species. the ones that are so close they are almost the same species, but aren't quite.
 
Not so. It is ONE mutation that allows their survival. One mutation in one family. One mutation that allows them to survive the higher levels of radiation, which are invariably fatal without that mutation.
 
at the very least you end up with 30 differnt races, in the D&D/tolken sense
 
That family will then be the ancestors of modern Parthans.
 
4:24 PM
your hobbits, elves, and dwarves. all different mutations of the same similar pathnos, but with deviations.
it doesn't work that simple. mutations aren't one thing
 
No, of course not. They have multiple effects.
 
I said that one species was 'suddnely' sapient, but that was lazy shorthand. evolution is about millions of tiny mutations.
 
But as long as it has that one effect, good enough.
It would undoubtedly have other effects as well.
 
and without a way to recombine genes that means that before the extinction event you would have pathos with varying lvel of genetic similarity.
 
Give me more credit for knowing biology. It is sort of my job.
 
4:26 PM
so many will be 'close' sapient, but not identical
 
Which is all fine.
 
it it's rather unlikely that all of these nearly-identical genetic siblings will be wriped out.
your getting races, probably lots of races. even with an extinction event.
though I think you could play with it.
through in yet another extinction event, more recently. This one viral.
 
No, because only the Parthans with the one specific mutation that (among other things) grants high radiation resistance will survive.
 
I don't think that one single mutation can protect against radiation resistance.
which is why I suggest a virus
 
Not in humans, perhaps
In a species with a different genetic material, and a different set of genes entirely?
Seems possible to me.
 
4:28 PM
same idea. but a single mutation can go a long way towards protecting against a virus. I find it much harder to accept a single mutation protecting against radiation.
 
Really?
Try this on for size
 
It's more of the physics of it. Radiation is not a single attack.
it's more like a million little attacks to a million cells at once.
 
Parthans have hard exterior exoskeletons.
A light exoskeleton is superior for most purposes
Heavy exoskeletons impair movement
 
hard exoskeletons wouldn't protect that much from mutation. what about mutagens consumed in food and water?
 
However, they also provide superior protection from cosmic radiation
Not so harmful compared to direct irraditation
 
4:30 PM
and besides, it seems less likely that a single mutation can completely change your exoskeleton without being crippling.
but okay, I do understand your idea.
 
It would be relatively crippling
it would never work
\
unless there was a sudden influx of radiation
 
we could cribble over specifics, point is that in an extinction event occures that only one mutation protected from.
 
Exactly
 
I would go with a differnt route for that final event, but okay.
 
And that one mutation preserves only a single family
 
4:32 PM
However, that makes everyone clonal now. the evolution of a male species, as original desired, is even harder to justify if everyone is completly identical.
 
!) Everyone is not clonal, because of high mutations at safe loci. Remember?
2) The OP does not want a male species to evolve, but to be engineered
 
and I think that they would still have the ingrained race-war mentality, even if there isn't any competing races to fight against; which I kind of hate since it would imply a psychology of intolerance would be the norm; not a fun race to write about.
hmm...okay safe loci mutation is harder to justify now, but maybe it could be...
 
Why would they need to have a race war mentality? It's been 100,000 years since there was another, similar race. By the way. Food and water would not be mutagens if the source of radiation was cosmic radiation, particularly gamma radiation.
 
what would triger the safe-loci mutations, if they now are resistant to all mutagens?
yes, but in that 100,000 years they have been mostly-clonal. even with the safe-loci mutation idea; it's unlikely that safe-loci would be something that affects evolutnary psychology (and if it IS then you get back to mutations that completely change the species and diverse species etc etc)
thus, despite there being little need for it any more, they would just keep cloneing the ingrained race-war mutation. There is no way to evolve out of it.
 
Ah, perhaps
No reason they can't get rid of it though, whether socially or genetically. Recall their level of development here.
They are NOT resistant to all mutagens! Not by a long shot.
They are resistant to the source of mutations that caused the apocalypse. In my case, radiation from some extraterrestrial source.
 
4:40 PM
maybe.... As much as I'm a huge fan of our social growth, and think were MUCH better then we were just a few generations ago, the fact is our genetic psychology still plays a key role in everything we do. We hate racism, it's still around. Even when we finally making headway towards removing the black/white racism we now find people hating arabs. We must moved the racism to another race. sadly society can't fully fix evolved psychology.
honestly, I kind of like my disease appoclapse idea. Because an adaptation that caused certain controled loci mutations would be a great way to beat disease.
 
I am afraid I strongly disagree. The mere fact that racism is much less common now indicates that society can have a huge effect on it.
 
if this world has all kids of pathnogentic species, then viruses would be evolved with that in mind. evolving to attack specific clonal species.
 
Free radicals? Ingested radioactive materials? All of these are mutation sources.
 
an adaptation could protect against one virus, until it adapts as well. An adaptation to constantly have small changes could thawt every strain of a particularly vicious virus that worked by targeting exact genetics of it's hosts.
 
Well, that is an interesting idea.
Makes me like your idea a bit more.
 
4:43 PM
oh, society can have a huge affect, don't get me wrong. but in a species that would likely have far more ingrained tendencies.. I think you could easily claim artisitic license there, but it would be nice to come up with an excuse to minimize the original evolution of such a trait. I tend to overy think all these tiny things ;)
 
Genetics lays the groundwork for personality. Socialization then has a huge influence on it.
The plasticity of the brain to external stimuli is incredible.
 
so say there were two key mutation points. One was evolution to resist the radiation which had been triggeriing all the mutation (after sapience had occured); because ultimately all the birth defects and harm of that much radiation was still worse then the evolution (in the short term)
 
ok
cool
 
later a virus is attacking them all and one species evolves loci-mutation as the only effective defense
 
hmm, yes
 
4:45 PM
that is the only one of many races of sapience to survive.
put that in the semi-recent past; to minimize the change due to more 'normal' mutation between then and now.
 
That sounds pretty solid.
 
I would imagine their adaptation against mutation would be less of preventing mutation from ever happening (which I still think is pretty had) but instead in error checking. They somehow screen gamets of their young to verify that they don't have mutations.
that way the adaptation that allows controled mutation would simply be to stop screening specific loci
 
That seems plausible.
 
easier way to justify a single genetic mutation having such a huge change.
okay. I think that works well. someone should post a message to the OP with what we decided was a viable evolutinary path, so he can benefit form our discussion. odds are he won't even see it otherwise
meanwhile; I'm going to go back to this 'work' thing I sometime do :D
 
OK. I will post it on the original question, giving you due credit. Seem ok?
Actually, that does not seem like enough space.
 
4:55 PM
feel free to post it however you would like.
and yes part of the reason for letting you do it is I figured you could likely truncate it to fit easier; I ramble in my explinations ;)
as an added note a species like this would most likely develop very advanced medical technolgy quickly, as disease will be a major risk to clonal species. so it makes sense they would develop the ability mess with their genetics; and a willingness to use it; it would be the only way to survive. adaption via technology due to lack of adaption via evolution
 
Yes, that was my though too.
 

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