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Old 01-03-2015, 01:07 PM
Happy Lendervedder Happy Lendervedder is online now
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Time travel and procreating with your bloodline (Need answer whenever)

Q1: Imagine "Johnny Timetravel"-- a handsome charmer a quarter of a century in years on earth-- were to head back to when his grandmother was a young, fertile lass of 22. She's a comely young woman with swivel-y child-birthing hips and ample bosom. Johnny falls madly in love with Grandma and Grandma falls madly in love with Johnny. If Johnny were to perform sexual intercourse on his grandmother shoot a sperm square into her ripe ovum, would their genetic material be considered "too closely matched" to produce offspring devoid of the usual incestuous problems?

How about if Johnny were to head back another 25 years into the past and perform the same sexual hibbidy-dibbidy on his great-grandmother? Would their spawn be healthy and vibrant and able to live a fine, upstanding life without genetic malfunctions?

How about if Johnny were to head back yet another 25 years and do the "it" with his great-great grandmother? How close are they genetically at four generations back?

In short how far back in time would Johnny have to go to impregnate an ancestor safely and soundly without risk of damaging the Timetravel gene pool?

Q2: If you were to look at the genetic material of all 32 of your great-great-great grandparents, would you have equal amounts from each of them, or will some of their genes get pushed out of the way along the way? Is it possible that my great-great-great grandson/daughter will have none of "me" in them anymore?
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Old 01-03-2015, 01:10 PM
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Since Johnny is the source of the genetic material for the bloodline and he's his own Grandpa (or more), it doesn't matter how far back he goes, he's an ancestor and decendent.
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Old 01-03-2015, 01:17 PM
Smapti Smapti is online now
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According to a documentary I once saw on the subject of past nastification, you'll grow up without a Delta brain wave, which may turn in handy if the Earth is ever invaded by giant brains.

Last edited by Smapti; 01-03-2015 at 01:18 PM.
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Old 01-03-2015, 01:23 PM
TimeWinder TimeWinder is offline
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At this point, we need to know what kind of time travel he's using. (No, I can't believe I said that, either).

If it's the "many worlds" type, where changes to the past don't affect the future, then this isn't any different from mating with any other close relative that shares 1/4 of your genes, say a first cousin.

On the other hand, if this is the "Back to the Future" type scenario, it's a lot more interesting. If you'll recall from that documentary, changes in the past cause the future to "update" in real time, and we get to do a fun game of "count the chromosomes." Johny's chromosomes come from four sources: his maternal grandmother (MgM), his maternal grandfather (MgF), and his paternal grandparents (PgM, PgF), ignoring a small amount of mutation and other genetic uniqueness. But the one of the "gF"'s here is Johnny himself.

If it's the maternal grandmother, this means that Johnny's mom has the genes of MgM + Johnny, part of which is MgM as well, which means that Johnny himself will get more genes from MgM, which will in turn mean that his mom has more MgM genes, which in turn means.... ultimately, Johnny's mother will end up being a clone of his maternal grandmother, containing effectively no genes not present in MgM. In this case, Johnny is effectively the offspring of his father and his maternal grandmother, genetically.

And that's the only case that works at all. You didn't specify which grandmother, but if it's the Paternal grandmother (PgM), the same reasoning applies, except that now Johnny's _father_ is a clone of PgM, which means Johnny's father is female, and Johnny fades out of ever photograph ever taken.
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Old 01-03-2015, 01:24 PM
Colibri Colibri is offline
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You don't have to hypothesize time travel to understand trans-generational crosses, since it happens with domestic animals all the time.

You share on average 1/4 of your genetic material with your grandparents by descent. You also share 1/4 of your genetic material with your first cousins (who share one of your sets of grandparents). So the genetic consequences are the same as having offspring with your first cousins.

You can calculate the degree of genetic similarity (by descent) simply by knowing the number of ancestors in that generation. You share 1/8 of your genetic material with your great-grandparents (same as second cousins), 1/16 with great-great-grandparents (same as third cousins), and so on.
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Old 01-03-2015, 01:30 PM
Happy Lendervedder Happy Lendervedder is online now
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Originally Posted by TimeWinder View Post
And that's the only case that works at all. You didn't specify which grandmother, but if it's the Paternal grandmother (PgM), the same reasoning applies, except that now Johnny's _father_ is a clone of PgM, which means Johnny's father is female, and Johnny fades out of ever photograph ever taken.
That sound you just heard was my brain esplodin'.
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Old 01-03-2015, 01:31 PM
Colibri Colibri is offline
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Originally Posted by Happy Lendervedder View Post
Q2: If you were to look at the genetic material of all 32 of your great-great-great grandparents, would you have equal amounts from each of them, or will some of their genes get pushed out of the way along the way? Is it possible that my great-great-great grandson/daughter will have none of "me" in them anymore?
Due to the phenomenon known as crossing over, there is a mixing of genetic material between chromosomes in each generation. Because of this it is possible to end up with some of the genetic material from some ancestors being eliminated by chance. However, I think it would probably take more than 5 generations for this to be likely.

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At this point, we need to know what kind of time travel he's using. (No, I can't believe I said that, either).
I understand this to be more a question about genetics than about time travel per se.
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Old 01-03-2015, 01:33 PM
Leo Bloom Leo Bloom is online now
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Excellent hed.

Also, OP was having a suspiciously good time writing the OP.

And "hibbidy-dibbity" is a new one on me, but is a keeper.

Last edited by Leo Bloom; 01-03-2015 at 01:37 PM.
  #9  
Old 01-03-2015, 01:38 PM
Happy Lendervedder Happy Lendervedder is online now
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Originally Posted by Colibri View Post
Due to the phenomenon known as crossing over, there is a mixing of genetic material between chromosomes in each generation. Because of this it is possible to end up with some of the genetic material from some ancestors being eliminated by chance. However, I think it would probably take more than 5 generations for this to be likely.
I see. And good to know.

Quote:
I understand this to be more a question about genetics than about time travel per se.
Answers on either would be welcome. Genetics was my first thought, but the consequences of time travel schnogging are also interesting...and critically important for the continuation of our species.

Last edited by Happy Lendervedder; 01-03-2015 at 01:40 PM.
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Old 01-03-2015, 02:01 PM
Colibri Colibri is offline
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Originally Posted by TimeWinder View Post
And that's the only case that works at all. You didn't specify which grandmother, but if it's the Paternal grandmother (PgM), the same reasoning applies, except that now Johnny's _father_ is a clone of PgM, which means Johnny's father is female, and Johnny fades out of ever photograph ever taken.
Not so. Johnny's Y chromosome came from his PgF's father. It was not inherited from his PgM in any way. His Y chromosome (which also does not undergo crossing over with the X) will be preserved intact regardless of the number of generations you go back. (His father's autosomal genes and X chromosome, however, may ultimately become identical to those of his PgM's.)
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Old 01-03-2015, 02:08 PM
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You don't even need to invoke crossing over. Even if you look at whole chromosomes as units, it's unlikely that an even mix will be passed on every generation.

I have 46 chromosomes. 23 are from my dad, and 23 are from my mom. When I make a sperm, that sperm could contain 23 of my dad's chromosomes, 23 of my mom's chromosomes, or (far more likely), some combination - say, 12 dad's and 11 mom's, or 14 mom's and 9 dad's.

Because of this, and considering that chromosomes are of different sizes, and tossing in recombination for good measure, you'd expect the mix in each generation to vary. It'll be, on average, close to 50/50, but it'll be a bell curve.

I am, of course, ignoring sex chromosomes, but they're only one pair out of 23.

Last edited by Smeghead; 01-03-2015 at 02:08 PM.
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Old 01-03-2015, 02:36 PM
Chronos Chronos is online now
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Yeah, the only case where you can get exact consanguinity numbers (other than identical twins, of course) is parent/child, who are guaranteed to be a 50% match. Any other relation, the numbers you calculate will only be an average, and could be higher or lower.
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Old 01-03-2015, 03:02 PM
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Originally Posted by Colibri View Post
You don't have to hypothesize time travel to understand trans-generational crosses, since it happens with domestic animals all the time.

You share on average 1/4 of your genetic material with your grandparents by descent. You also share 1/4 of your genetic material with your first cousins (who share one of your sets of grandparents). So the genetic consequences are the same as having offspring with your first cousins.

You can calculate the degree of genetic similarity (by descent) simply by knowing the number of ancestors in that generation. You share 1/8 of your genetic material with your great-grandparents (same as second cousins), 1/16 with great-great-grandparents (same as third cousins), and so on.
Wouldnt you share 1/2 of your genetic material with your first cousins since you share 1/2 of the grandparents?
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Old 01-03-2015, 03:09 PM
Idilia Dubb Idilia Dubb is offline
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Didn't Heinlein deal with this? IIRC, Laz Long does the deed with his g-granddaughter, justifying that he and she haven't enough genetic material in common to make it incest.
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Old 01-03-2015, 03:28 PM
Colibri Colibri is offline
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Wouldnt you share 1/2 of your genetic material with your first cousins since you share 1/2 of the grandparents?
No, because the 1/4 that is passed on from each grandparent is independent of the 1/4 that is passed on from the other grandparent in each family.
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Old 01-03-2015, 04:07 PM
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Why the assumption that a child of Johnny & Great-Grandma is Johnny's grandfather rather than a great-uncle / great-aunt? It seems to require much less messing with history to have a one-off fling than to erase one's great-grandfather.
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Old 01-03-2015, 08:47 PM
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Quoth Idilia Dubb:

Didn't Heinlein deal with this? IIRC, Laz Long does the deed with his g-granddaughter, justifying that he and she haven't enough genetic material in common to make it incest.
Nearly everyone in the galaxy is a descendant to some degree of Lazarus Long, but I don't think he ever slept with any of them as close as three generations. Aside from his two gender-swapped clones or his mother, of course.
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Old 01-03-2015, 09:06 PM
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You don't even need to invoke crossing over. Even if you look at whole chromosomes as units, it's unlikely that an even mix will be passed on every generation.
It might be pointed out, however, that crossing over delays the complete elimination of genetic material from some ancestors. By the time you get to the sixth generation back, you have more ancestors (64) than chromosomes (46). If chromosomes were inherited as units, then at least 18 (and probably more) of your ancestors would be completely unrepresented in your genome. Crossing over means that some of their genes will probably still be represented by at least some fragments of your chromosomes.
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Old 01-04-2015, 04:41 AM
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Nearly everyone in the galaxy is a descendant to some degree of Lazarus Long, but I don't think he ever slept with any of them as close as three generations. Aside from his two gender-swapped clones or his mother, of course.
In fact, in the first book he appeared in (Methuselah's Children) he refuses to have a relationship with a woman who's his great-great-grandaughter, I think (possibly another "great" in there). She has no problem with the distant consaguinity, though.

When I first saw the thread subject, I thought of a different Heinlein story, but perhaps we should leave that until this thread is zombified
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Old 01-04-2015, 07:13 AM
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Originally Posted by Colibri View Post
You share on average 1/4 of your genetic material with your grandparents by descent. You also share 1/4 of your genetic material with your first cousins (who share one of your sets of grandparents). So the genetic consequences are the same as having offspring with your first cousins.
I think you share 1/4 (on average) of genetic material with your parent's sibling, and 1/8 with your first cousins.

Of course, really, most human DNA is the same anyway, but you know what I mean.
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Old 01-04-2015, 07:54 AM
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In fact, in the first book he appeared in (Methuselah's Children) he refuses to have a relationship with a woman who's his great-great-grandaughter, I think (possibly another "great" in there). She has no problem with the distant consaguinity, though.
One of the entire reasons for the Howard Project was to interbreed long-lived people. The long-term effects were (a) long-lived people and (b) birth defects. Also, lots of redheads. Scientifically, he had cause to be concerned about birth defects.

Also, at that point, he's still within a couple normal lifetimes of having been raised in Missouri in the 20's. I always read the consanguinity issues as avoiding the real issue, which is that he didn't want to do it with one of his kids. By the time he's having sex with his mom, his clone-sisters, his transgender partner of a couple centuries and a couple of human-bodied Pinocchio computer sex-kittens, I think he's past that little quibble.
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Old 01-04-2015, 08:05 AM
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Since there is crossover, you will share, almost certainly, very close to 50% of each of your parent's and 25% of each grandparent's genes. But taking TimeWinder's scenario, assuming you were your own grandpa, you would end up with 1/4 + 1/16 + 1/64 + ... = 1/3 of your grandmother's genes and 1/7 of your grandmother's genes if you did it with her instead.
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Old 01-06-2015, 04:44 PM
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Originally Posted by Colibri View Post
It might be pointed out, however, that crossing over delays the complete elimination of genetic material from some ancestors. By the time you get to the sixth generation back, you have more ancestors (64) than chromosomes (46). If chromosomes were inherited as units, then at least 18 (and probably more) of your ancestors would be completely unrepresented in your genome. Crossing over means that some of their genes will probably still be represented by at least some fragments of your chromosomes.
Is there any point where it's a near-100% certainty that your ancestors/descendants will not have any of your genetic material anymore? Is it possible my dreamy bedroom eyes won't make it to the 100th generation?
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Old 01-06-2015, 08:55 PM
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According to a documentary I once saw on the subject of past nastification, you'll grow up without a Delta brain wave, which may turn in handy if the Earth is ever invaded by giant brains.
Thank you for this.
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Old 01-06-2015, 08:58 PM
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If you genuinely have dreamy bedroom eyes, then those will probably persist for quite a few generations, and might even become the default for humanity as a whole. If, on the other hand, your eyes are of merely normal seductive quality, then it's a crapshoot.
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Old 01-07-2015, 12:05 PM
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Originally Posted by Happy Lendervedder View Post
Is there any point where it's a near-100% certainty that your ancestors/descendants will not have any of your genetic material anymore? Is it possible my dreamy bedroom eyes won't make it to the 100th generation?
The answer will be hugely different if we're talking about "any" of your genetic material, or specifically about the, oh, handful or so of genes which code for your ocular dreaminess.
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Old 01-08-2015, 05:49 PM
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And that's the only case that works at all. You didn't specify which grandmother, but if it's the Paternal grandmother (PgM), the same reasoning applies, except that now Johnny's _father_ is a clone of PgM, which means Johnny's father is female, and Johnny fades out of ever photograph ever taken.
I didn't take the OP's question as him wanting to become his own predecessor.

What if he waited until his natural predecessor was born and did the deed after that; likely an adulterous situation... He would end up with a great-great auntie or uncle that has a bunch of his DNA.
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Old 01-08-2015, 06:20 PM
Lemur866 Lemur866 is offline
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If we're not talking about the problems of becoming your own literal grandpa, the match between you and your grandmother are no closer than the one between first cousins, which is legally/socially approved in many localities. There may be a slight increase in the incidence of the expression of hereditary diseases, but not strikingly so.

The real effects of inbreeding come when you have repeated pedigree collapse. If your parents and aunt and uncle were also first cousins, marrying your first cousin means your offspring only have 4 great-grandparents instead of the expected 8--which is as close as a sibling mating.
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Old 01-09-2015, 08:49 AM
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I forget which Heinlein book it was, but in one of the later stories Lazarus Long ends up with two "daughters" Lazi and Lupi who are genetically identical to him except that they don't have a Y chromosome. The two young women convince him to have a threesome with them by saying it's basically masturbation (hah!) but also they point out that inbreeding is only bad if it reinforces bad recessive genes and the evidence suggests that Lazarus doesn't have any of those to reinforce. Then he goes back in time and has sex with his own mother. RAH was a weird person.

It's worth noting that, in large populations of cats and dogs, this sort of thing happens regularly. Animals end up mating with their own siblings or parents no more and no less frequently than anyone else in the colony, and that generally doesn't produce terrible effects. In a pride of lions, the alpha male will have no reluctance to mate with his own daughters. But when humans do this sort of thing, it's usually not accidental, it's done on purpose. For example, trying to keep the family tree of the royal family from including any peasants. THAT'S when you run into trouble.

Last edited by sbunny8; 01-09-2015 at 08:54 AM.
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Old 01-09-2015, 09:27 AM
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The real effects of inbreeding come when you have repeated pedigree collapse. If your parents and aunt and uncle were also first cousins, marrying your first cousin means your offspring only have 4 great-grandparents instead of the expected 8--which is as close as a sibling mating.
This could also happen if two siblings from one family marry two siblings from another family.
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Old 01-09-2015, 11:05 AM
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Is there any point where it's a near-100% certainty that your ancestors/descendants will not have any of your genetic material anymore?
Well, remember your 100th generation descendant has to get their eye genes from somewhere. So there's certainly a positive chance they'll get one from you. In fact, assuming you do end up having a 100th generation descendant, the odds of them getting a particular gene from you have to be at least one in 7 billion or so (based on the current world population). Some quick analysis and very reasonable assumptions could probably get the odds down a lot farther.

That's leaving aside whether the gene mutates between you and them. Up to you whether that would be the "same" "gene" or not, if it's a direct copy from yours but with a copying error along the line.

Now, if your bedroom eyes are the result of the interaction of multiple genes, then things start getting much more ugly, since you'd need the 100th generation-vedder to get all of the appropriate genes, exponentially worse odds the more genes are involved. And of course, you'd need to also cut the odds for the chance of a mutation that changes things bedroom-wise.


[And of course, this is all based on the assumption that humans are going to continue biological mating with random meiosis, and no genetic engineering. Not something I'd really expect 100 generations from now, but we can only go with what we know]

Last edited by Quercus; 01-09-2015 at 11:06 AM.
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Old 01-09-2015, 11:44 AM
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[And of course, this is all based on the assumption that humans are going to continue biological mating with random meiosis, and no genetic engineering. Not something I'd really expect 100 generations from now, but we can only go with what we know]
People like Kurzweil want to mate with computers now, and Gates wants to kill 95% of the population, so, nothing will exist in 100 generations from now except solar powered computers with downloaded human brains.
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Old 01-09-2015, 12:11 PM
Lemur866 Lemur866 is offline
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Well, remember your 100th generation descendant has to get their eye genes from somewhere. So there's certainly a positive chance they'll get one from you.
Also note that, if you have any 100th generation descendants, you'll likely be an ancestor of lots of people if not most people, and you'll likely show up in multiple ancestor slots for a particular person.
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Old 01-09-2015, 01:06 PM
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In fact, in the first book he appeared in (Methuselah's Children) he refuses to have a relationship with a woman who's his great-great-grandaughter, I think (possibly another "great" in there). She has no problem with the distant consaguinity, though.

When I first saw the thread subject, I thought of a different Heinlein story, but perhaps we should leave that until this thread is zombified
Don't forget "Time For The Stars" where IIRC the implication is that after getting back, he will carry on with his (greatgreat?)granddaughter.

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No, because the 1/4 that is passed on from each grandparent is independent of the 1/4 that is passed on from the other grandparent in each family.
Two siblings get a random selection of the genetic material of their parents, so they will be 50% match typically. However, each child of those siblings will only get half (typically) of the genetic material; but their choices too are independent. Child AA of Parent A may get say, 25% of what came from the grandparents and matches parent and uncle/aunt B. Child BB will get a different set of 25% from that matching 50%, so they will in fact only (typically) match AA to BB about 12.5%.
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Old 01-09-2015, 01:39 PM
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Don't forget "Time For The Stars" where IIRC the implication is that after getting back, he will carry on with his (greatgreat?)granddaughter.
His great-grandniece, the great-granddaughter of his brother. Although since his brother was his identical twin, genetically she'd be the same consanguinity as his great-granddaughter.
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Old 01-09-2015, 02:02 PM
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Also note that, if you have any 100th generation descendants, you'll likely be an ancestor of lots of people if not most people, and you'll likely show up in multiple ancestor slots for a particular person.
Exactly. If that 100th-gen descendant had completely unique ancestors in this generation, that would be 2^100 ancestors today, but there are only about 2^32 people alive today.

So even if every single person alive today had descendants which interbred such that every signle person alive today was an ancestor of that 100th-gen-vedder, then Happy would still on average contribute 1/7 billionths of their genes.
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Old 01-09-2015, 02:07 PM
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According to a documentary I once saw on the subject of past nastification, you'll grow up without a Delta brain wave, which may turn in handy if the Earth is ever invaded by giant brains.
Oh, a lesson in not changing history from Mr. "I'm My Own Grandfather"!
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Old 01-09-2015, 02:28 PM
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Exactly. If that 100th-gen descendant had completely unique ancestors in this generation, that would be 2^100 ancestors today, but there are only about 2^32 people alive today.

So even if every single person alive today had descendants which interbred such that every signle person alive today was an ancestor of that 100th-gen-vedder, then Happy would still on average contribute 1/7 billionths of their genes.
The Lendervedder blood lives on!
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Old 01-09-2015, 03:22 PM
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Also consider that, 100 generations hence, you'll probably have a lot of descendants. The odds of any particular one having any particular gene from you is slim, but the odds of any particular gene of yours living on in any of them are pretty good.
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Old 01-09-2015, 08:13 PM
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I don't think you need a time machine to be your own grandfather. You just need to live in Kentucky.
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Old 01-09-2015, 08:24 PM
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When I first saw the thread subject, I thought of a different Heinlein story, but perhaps we should leave that until this thread is zombified
FWIW, All You Zombies has been adapted into a movie called Predestination. I haven't read the story but the I thought the movie was pretty good. It apparently adds a bit to the short story but preserves the underlying structure pretty faithfully.
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Old 01-09-2015, 08:28 PM
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Quote:
Originally Posted by Dr. Strangelove View Post
FWIW, All You Zombies has been adapted into a movie called Predestination. I haven't read the story but the I thought the movie was pretty good. It apparently adds a bit to the short story but preserves the underlying structure pretty faithfully.
I just want to say you have a good user name for participation in this thread.

Last edited by Siam Sam; 01-09-2015 at 08:28 PM.
  #43  
Old 01-09-2015, 08:50 PM
BigT BigT is offline
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Here are my thoughts: In the single timeline time travel scenario, you still have half of your genes coming from your mom and your dad. But one of your parents will have to have half of their genes from you. Assuming they give that half back to you, then the other parent would also have to have half your genes.

So unless you went back and got both your grandmothers pregnant, I'd be looking into how closely related your parents really are.
  #44  
Old 01-09-2015, 10:48 PM
Irishman Irishman is offline
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Quote:
Originally Posted by Happy Lendervedder View Post
If Johnny were to perform sexual intercourse on his grandmother shoot a sperm square into her ripe ovum, would their genetic material be considered "too closely matched" to produce offspring devoid of the usual incestuous problems?
Too closely matched to be devoid of the problems of incest? I think you lost your train of thought. Too many double negatives, perhaps. The problems of incest are precisely because of being too closely matched. What you're asking for is being distant enough to be devoid of problems, or close enough matched to start causing problems. Or something.

Quote:
How about if Johnny were to head back another 25 years into the past and perform the same sexual hibbidy-dibbidy on his great-grandmother? Would their spawn be healthy and vibrant and able to live a fine, upstanding life without genetic malfunctions?
Technically, that's impossible to know, as any baby has a risk of being genetically deficient. We can answer the question statistically, but not absolutely.



Quote:
Originally Posted by madsircool View Post
Wouldnt you share 1/2 of your genetic material with your first cousins since you share 1/2 of the grandparents?
Each grandparent contributes to each grandchild independently. PgF and PgM give rise to Daddy and Uncle*. MgF and MgM give rise to Mommy. Auntie's parents are some other couple.

Daddy and Uncle share 50% consanguinity. Uncle's kiddoes get 1/4 from PgF and 1/4 from PgM. You get 1/4 from PgF and 1/4 from PgM.

Quote:
Originally Posted by Dr. Drake View Post
Why the assumption that a child of Johnny & Great-Grandma is Johnny's grandfather rather than a great-uncle / great-aunt? It seems to require much less messing with history to have a one-off fling than to erase one's great-grandfather.
Because what's the point of time travel incest if not to make it self-ancestoring?


Quote:
Originally Posted by Idilia Dubb View Post
Didn't Heinlein deal with this? IIRC, Laz Long does the deed with his g-granddaughter, justifying that he and she haven't enough genetic material in common to make it incest.
I think you're talking about the aforementioned Time for the Stars, where the hero returns from space travel to marry his great grandniece from his twin brother.


Quote:
Originally Posted by Ethilrist View Post
Also, at that point, he's still within a couple normal lifetimes of having been raised in Missouri in the 20's. I always read the consanguinity issues as avoiding the real issue, which is that he didn't want to do it with one of his kids. By the time he's having sex with his mom, his clone-sisters, his transgender partner of a couple centuries and a couple of human-bodied Pinocchio computer sex-kittens, I think he's past that little quibble.
Transgender partner? You lost me.

Quote:
Originally Posted by Hari Seldon View Post
Since there is crossover, you will share, almost certainly, very close to 50% of each of your parent's and 25% of each grandparent's genes. But taking TimeWinder's scenario, assuming you were your own grandpa, you would end up with 1/4 + 1/16 + 1/64 + ... = 1/3 of your grandmother's genes and 1/7 of your grandmother's genes if you did it with her instead.
Um, what? 1/3 of your grandmother's genes, or 1/7 of her genes?

Quote:
Originally Posted by sbunny8 View Post
I forget which Heinlein book it was, but in one of the later stories Lazarus Long ends up with two "daughters" Lazi and Lupi who are genetically identical to him except that they don't have a Y chromosome. The two young women convince him to have a threesome with them by saying it's basically masturbation (hah!) but also they point out that inbreeding is only bad if it reinforces bad recessive genes and the evidence suggests that Lazarus doesn't have any of those to reinforce. Then he goes back in time and has sex with his own mother. RAH was a weird person.
Of course, by the time Lorelei and Lapis show up, it is well in the future, and one can surmise that (a) birth control is a strong science; (b) any breeding can be genetically monitored/tweaked after conception. In which case, sex with his clones is as risky as masturbation.



Quote:
Originally Posted by vomit_comet View Post
.... and Gates wants to kill 95% of the population,
Erm, what?
  #45  
Old 01-10-2015, 06:21 AM
chorpler chorpler is offline
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Quote:
Originally Posted by Irishman View Post
Too closely matched to be devoid of the problems of incest? I think you lost your train of thought. Too many double negatives, perhaps. The problems of incest are precisely because of being too closely matched. What you're asking for is being distant enough to be devoid of problems, or close enough matched to start causing problems. Or something.
I think that is indeed what he said. Too closely matched to not start having inbreeding problems.

Also, I too would like to know what the thing about Bill Gates wanting to kill 95% of the world was about.
  #46  
Old 01-10-2015, 01:42 PM
Irishman Irishman is offline
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I guess the double negatives got me.
  #47  
Old 01-10-2015, 06:59 PM
vomit_comet vomit_comet is offline
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Quote:
Originally Posted by Irishman View Post
Too closely matched to be devoid of the problems of incest? I think you lost your train of thought. Too many double negatives, perhaps. The problems of incest are precisely because of being too closely matched. What you're asking for is being distant enough to be devoid of problems, or close enough matched to start causing problems. Or something.



Technically, that's impossible to know, as any baby has a risk of being genetically deficient. We can answer the question statistically, but not absolutely.





Each grandparent contributes to each grandchild independently. PgF and PgM give rise to Daddy and Uncle*. MgF and MgM give rise to Mommy. Auntie's parents are some other couple.

Daddy and Uncle share 50% consanguinity. Uncle's kiddoes get 1/4 from PgF and 1/4 from PgM. You get 1/4 from PgF and 1/4 from PgM.



Because what's the point of time travel incest if not to make it self-ancestoring?




I think you're talking about the aforementioned Time for the Stars, where the hero returns from space travel to marry his great grandniece from his twin brother.




Transgender partner? You lost me.



Um, what? 1/3 of your grandmother's genes, or 1/7 of her genes?



Of course, by the time Lorelei and Lapis show up, it is well in the future, and one can surmise that (a) birth control is a strong science; (b) any breeding can be genetically monitored/tweaked after conception. In which case, sex with his clones is as risky as masturbation.





Erm, what?

Erm, Watch Bill Gates' Ted Talk, where he talks about depopulation of the earth using vaccines.
  #48  
Old 01-10-2015, 08:30 PM
Siam Sam Siam Sam is offline
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Originally Posted by vomit_comet View Post
Erm, Watch Bill Gates' Ted Talk, where he talks about depopulation of the earth using vaccines.
Somehow I feel you've misunderstood something.
  #49  
Old 01-10-2015, 08:45 PM
vomit_comet vomit_comet is offline
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Here's a quote from Bill Gates after being asked a question from Sanjay Gupta...

To me it seems like Mr. Gates is talking out of both sides of his mouth and trying not to let on to something deeper.

He says he wants to reduce disease caused childhood deaths by half, putting those children into eventually adulthood and procreating, yet in the same sentence he says he wants to reduce population growth.

The rate of growth of population in western world is already reduced to a level that cannot be recovered from. This is from purely a capitalist viewpoint, Capitalism cannot be sustained the way it has been for the last 80 or so years without grown of population at a certain rate. Bill, being one of the biggest capitalists I can think of double talking like this just sounds too shady to me.

Dr. Sanjay Gupta: Ten billion dollars [pledged] over the next 10 years to make it “the year of the vaccines.” What does that mean exactly?

Bill Gates: Over this decade, we believe unbelievable progress can be made, in both inventing new vaccines and making sure they get out to all the children who need them. We could cut the number of children who die every year from about 9 million to half of that, if we have success on it. We have to do three things in parallel: Eradicate the few that fit that profile — ringworm and polio; get the coverage up for the vaccines we have; and then invent the vaccines — and we only need about six or seven more — and then you would have all the tools to reduce childhood death, reduce population growth, and everything — the stability, the environment — benefits from that.
  #50  
Old 01-10-2015, 09:06 PM
Colibri Colibri is offline
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Quote:
Originally Posted by vomit_comet View Post
Here's a quote from Bill Gates after being asked a question from Sanjay Gupta...

To me it seems like Mr. Gates is talking out of both sides of his mouth and trying not to let on to something deeper.

He says he wants to reduce disease caused childhood deaths by half, putting those children into eventually adulthood and procreating, yet in the same sentence he says he wants to reduce population growth.

The rate of growth of population in western world is already reduced to a level that cannot be recovered from. This is from purely a capitalist viewpoint, Capitalism cannot be sustained the way it has been for the last 80 or so years without grown of population at a certain rate. Bill, being one of the biggest capitalists I can think of double talking like this just sounds too shady to me.

Dr. Sanjay Gupta: Ten billion dollars [pledged] over the next 10 years to make it “the year of the vaccines.” What does that mean exactly?

Bill Gates: Over this decade, we believe unbelievable progress can be made, in both inventing new vaccines and making sure they get out to all the children who need them. We could cut the number of children who die every year from about 9 million to half of that, if we have success on it. We have to do three things in parallel: Eradicate the few that fit that profile — ringworm and polio; get the coverage up for the vaccines we have; and then invent the vaccines — and we only need about six or seven more — and then you would have all the tools to reduce childhood death, reduce population growth, and everything — the stability, the environment — benefits from that.
Moderator Note

This is getting well off track with regard to the questions posed in the OP. Let's stick to the questions raised there. If you want to discuss this, please open a new thread in Great Debates.

Colibri
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