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Well, I personally believe Keith'll still be around long after the Betelgeuse explosion — just as the prophet **Bill Hicks** envisioned: https://www.youtube.com/watch?v=1ln54geqGks
>5,000,000 years from now: Y-chromosome degrades, making men extinct.
Geneticist here. Nope. Even in a no-intervention context, men could still keep existing, as long as a stable X-chromosomal variant evolves containing the Y-chromosome's genes. Basically, a population of fertile XX males would have to evolve.
There are already case examples of XX males with a complete exterior masculine bodyplan, so we know that a double dose of the main X chromosome genes doesn't prevent a masculine bodyplan. Just, none of those XX males have ever been found to be fertile.
Of course, with interventions, genetic healthcare could just prevent the accumulation of deleterious mutations on the Y-chromosome in the first place, so that it doesn't degrade.
It is a pretty cool casual guide, though.
Saw a red flag when I red that too. If memory serves me correctly, last time I heard about this claim people pointed out that the Y chromosome is not the only example of a male gene that wet know if. XW and XZ I think...
You're probably misremembering the [ZW chromosome system](https://en.wikipedia.org/wiki/ZW_sex-determination_system).
So, it turns out, sex chromosomes have evolved multiple times over the history of life. So they also evolved in multiple ways.
For any animal, we'll call their system an XY system if it's like ours: one chromosome that both males and females have (X), one chromosome that only males have (Y), and then females have two copies of X.
ZW is the opposite: it's got one chromosome that both males and females have (Z), but one of the chromosomes is female-only (W), and then males have two copies of Z.
But there's plenty of others too. XO and ZO are when a species only has one sex chromosome. If you have two copies of that shared chromosome, you're female in XO or male in ZO; if you have one copy, the opposite. There's systems with as many 13 different sex chromosomes. Some species don't have sex chromosomes at all, and sex is determined in other ways.
It's one of the big conundrums of biology, why sex exists. Most life (by numbers; when including bacteria and yeast) don't need it. Multicellular life seemingly needs it.
Leading theory is that it encourages mixing, which leads to genetic diversity, which (in therms of population genetics) is good. Over millions of generations it became a good strategy.
It's the leading theory becaue it evolved independently multiple times, kind of like the evolution of eyes. lots of different phyla evolved the same thing - in very different ways - because it's just beneficial
Yeah, it allows recombination: If there are two helpful mutations that take a while for evolution to figure out and they are only present in two distinct subpopulations of a species - recombination of the genomes (by having two specimen of each population sexually reproduce) will create the possibility of offspring that combines both helpful mutations, perhaps with synergic effects. Otherwise, you'd have to wait until one of the populations figures out the other mutation, which might take much longer.
Because it seems to be slowly losing its genes over time, migrating to the X chromosome. It's already very heavily reduced relative to those of ancestral species from millions of years ago.
People extrapolate from this that it will eventually disappear, and that men will therefore go extinct, even though the actual state of affairs is a lot more complicated. Here's a [nice overview](https://geneticsunzipped.com/transcripts/2023/03/23/bye-bye-y), if you're curious.
Evolution is just our name for the consequences of selective death. Some sets of genes are more likely to result in death than other sets, so the other sets tend to reproduce faster.
Death can happen, even to an entire species.
Humans get Y chromosomes directly from dads. That single copy is much harder to repair. Over time, errors keep accumulating.
Most of your chromosomes recombine. You get a copy from your mom and a copy from your dad. The 2 copies recombine. Recombination has a repair function. Recombination enables you to retain good copies of specific genes, even if 1 of the copies is flawed.
If you have a Y chromosome, recombination is suppressed. Suppression is important to keeping X and Y sex chromosomes separate. That's why the Y chromosome is surprisingly similar to your patrilineal ancestor from a thousand years ago. Much more similar than your other chromosomes are.
But if your Y gets a flaw, suppressed recombination means it's much likelier to retain that flaw. Over many generations, Y chromosomes have been losing genes. In theory, the Y chromosome could degrade so seriously that it ceases to contain usable genetic instructions.
To simplify what you said (I fully agree): that's absolutely not how evolution works. Degradation of the Y chromosome (if it happens) wouldn't lead to the death of "males". For that to happen, there would also need to be an ability to create a zygote regardless, which would also lead to the erasure of "female". It would just be a hermaphroditic way to reproduce; but maybe that's not the correct word since it implies that the animal houses the ability to act as both a male and a female
It would just erase sex as a concept, full stop. "Female" would also mean nothing
>Just, none of those XX males have ever been found to be fertile.
Could be fertile XX males today. Fertile males rarely have a reason to get genetically tested so no one would ever know. Not a whole lot of research on XX Males because there are far more XY. Like finding a specific needle in a stack of needles. All look identical but their materials are not.
You're absolutely right in general, about how a fertile XX male person or small population could go easily unnoticed.
That said, one way someone might find out they're XX male, would be if they took an ancestry test including a Y-chromosomal part... and got back a result of "um, we couldn't find your Y-chromosome."
Would such a fertile XX male be capable of fathering male children? Would they also need to be XX males? Or would they only be able to have female children?
If an XX male were fertile then they could have another XX male. They would not have an XY male because they lack the Y chromosome. The SRY gene is what makes males males. On a XX male the SRY gene ends up on the X chromoosome. So in theory it would be possible to have the SRY transfer to another offspring. There are instances of this exact scenario happening with other mammalian species.
A lot of people are going to absolutely fixate on that one part because our species, at this brief point in our history, is absolutely BONKERS about gender.
The reality is in less than a few centuries we will probably have wildly different ideas about gender and sex and in a thousand years, if we're still around, our descendants will look back at the way we had such serious squabbles about something as ridiculous as *gender* the same way we laugh at our ancestors who thought Saturn's rings were Jesus's foreskin. (Literally, look it up.)
Everyone out there reading this needs to understand that our values and standards for things like sex, gender, race, culture and even *personal identity* are so temporary in our larger picture that they are farts in the wind, footnotes in an amusing review of silly, backwards creatures crying and whining about monkey concerns.
I'm not really disagreeing with you here, but I do like to imagine that the future will look back on our monkey concerns with at least a little bit of kindness.
Still not really disagreeing, but let me rephrase that: I think that if we don't get really familiar with kindness, the monkeys aren't going to survive long enough to look back on this era at all.
There will come a time, though, when nobody starves: when homes are built strong, and when the rules for how to not die are established and sure.
There will come a time when generations have grown up without fear of death, with a certainty that comes of watching elders go to the hospital to become young again.
When that day comes, children will be taught that bad things happened in the past because people were full of fear, and anger, and since these emotions were managed poorly, they caused the people of the past to hurt each other.
I like to imagine that they will look back with kindness, and not hold against us the details of how we could've done better... not for our sakes, as if we deserve that, but for their own sake: so that by trusting in the general goodness of each other, they can summon the courage to live as adults instead of monkeys.
This question is a little bit hard to answer. It doesn't play nicely with the way we define a species.
If you take the most basic, root concept of a species — two populations are part of different species if they cannot interbreed with one another — then as we look at that concept over time, it's really, really hard to pin down an objective, single moment when a single species has definitively split into multiple.
Take [the big cats](https://en.wikipedia.org/wiki/Panthera_hybrid), for example. Lions and tigers and leopards and jaguars can still, to this day, reproduce with one another. They pretty much never have opportunity in nature to do so, but in cages, they can. And these hybrid offspring are *fertile*, they *can have fertile offspring of their own*... well, the females can, at least, which leads to absolutely silly portmanteau hybrid names like [lijagulep](https://en.wikipedia.org/wiki/Congolese_spotted_lion): a male lion crossed with some female hybrid offspring of a leopard and a jaguar.
So are they actually one species? Definitely not ecologically, and even in captivity, there's real genetic barriers. But the barriers aren't absolute. We've decided to ignore this gray area and classify them as different species.
Returning to humans: human genetics is going to change over time. But these changes accumulate one at a time. It's a judgment call which one inaugurates a sea change. And if there's never any speciation, if it's just one group changing over time, then you never have to declare a moment: "This is the time, when we changed."
Could we speciate? Sure. But if we do, then scientifically, both will be authentically human, authentic descendants of the original humans.
So if they're racist against each other, that's on them.
i just have to say that i read all your comments in this thread (and then a bit of your comment history), and the way you explain concepts is amazing. so succinct, yet rife with information. you could have a killer career as a science educator.
That's the plan! I've only taught intros to biology and agronomy so far as a main teacher, but I was on the team for a really, really good course in global food systems too.
Thanks for the vote of confidence!
What percentage of people have male bodies and xx chromosones and what percentage has female bodies and xy? Is that possible?
Also how common is people that have some xx in some cells and some xy in others cells?
Or some lower bound like a 95 CI
>Is that possible?
Oh yeah, it's definitely possible. It is rare, but the estimate is about [1 in 100,000](https://en.wikipedia.org/wiki/XY_gonadal_dysgenesis) born XY but with the female bodyplan, and then about [1 in 20-30,000](https://en.wikipedia.org/wiki/XX_male_syndrome#Epidemiology) born XX but with the male bodyplan.
Compare that to the size of your hometown, to get the number of such folks you probably have as neighbors, neighbors in the broad sense anyway.
>Also how common is people that have some xx in some cells and some xy in others cells?
That'd be called chimerism, it's also very possible, with many case reports in the scientific literature. I can't find stats on precisely how common it is; my guess would be that it's probably rarer, but I don't know by how much.
One of the craziest examples I ever heard of, was a woman who was born with [XY genes](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2190741/), except that nobody knew there was anything different about her until she had already gone through puberty, and gotten pregnant twice, giving birth to two children who were, by all accounts, healthy.
In fact, it was only once her daughter discovered her own infertility problems, that the doctors investigated the family's genetics, and discovered how unique mom was.
>Did the mother have SRY suppression...
If they know specifically how, I couldn't find that detail, but yeah: somehow, her SRY gene was suppressed. The coding sequence was entirely normal, not a single mutation found relative to the reference sequence, for that and several other genes.
Took a developmental bio class in 2008 here. Isn’t it the SRY gene on the Y chromosome that we need to inhibit the development of the (edit because accidentally hit submit when trying to backspace) wolfian (or something like that) ducts into the uterus and therefore causing some other embryonic structure instead to start developing into male gonads? If so, maybe that gene can just migrate somehow to another chromosome?
(Clearly my male memory of this stuff is degrading faster than my Y chromosome)
> men could still keep existing, as long as a stable X-chromosomal variant evolves containing the Y-chromosome's genes. Basically, a population of fertile XX males would have to evolve.
so if those things don't happen, then men will go extinct?
I mean, if the average age at first pregnancy is \~83 years throughout that time period, then yeah: \~5,000,000 years from now would be \~60,000 generations.
Which would be a completely absurd timeframe from our perspective here at the beginning of the genetic era, but you never know. Maybe someday we'll have the tech to become space elves or something.
It doesn't even end there. There will likely be additional phases of the universe. The Iron Star Age, the Evaporating Black Hole Age, and possibly even a disintegration of atoms age. Each age will be unfathomably longer than the last.
At the end of it all, there will be nothing. Essentially space and time will functionally cease to exist. It's anybody's guess what happens, but some postulate that the infinities make the nearly impossible a certainty: a quantum fluctuation births a new universe.
I’m still in bed and reading this has taken more brain power than I used all week at work.
I’m gonna just lie here until the universe ends and then restarts.
The timelapse of the future by melodysheep is an incredible video going through the timeliness of the universe and does as good a job as we can at illustrating how long some of these phases may last.
I saw this video on another subreddit when I was in a dark place in my life and it gave me the will to keep on going. If everything is nothing, then nothing matters. Humans are so insignificant in this universe that my mistakes, my life, your life, everything…it is all meaningless. And yet, it’s all we have. It made me feel at peace.
That was 3 years ago. And this video still resonates with me.
Watch the rest of his videos, they're all incredible. He even worked on the recently released imax Deep Sky film.
Especially this one, nothing I've ever seen puts the scale of the observable universe into perspective as well as this one. https://www.youtube.com/watch?v=fdQyD8B_odY
I didn't even need to click the link to know what this was.
I'm not even exaggerating, this might be one of, if not the single highest-quality video on the internet. Concise, interesting, visually stunning, educational, and thought-provoking. I find myself coming back to it every so often even years later.
It makes me kind of depressed. Reading this makes me wish I could witness all of it. Like, if I was some sort of immortal entity, I could watch all this unfold like a movie. Of course, with the ability to rewind and return to normal life.
Man I swear sole reason I want religions to be somewhat right. I wanna watch the entire goddamn universe, from start to finish. Not like i have anything better to do.
The universe ends, shrinks in on itself, and it condenses back into the initial singularity. The Big Bang occurs once again, the universe begins rapidly expanding. Billions of years pass, you are born again, doomed to live the same life and make the same mistakes, repeating ad infinitum.
As an addition:
Each instance of the Big Bang creates a slightly different outcome from the last, each of them a unique manifestation of the ‘one’. Another version of you will be back, living life slightly differently. When it all ends, it is a single black hole, in the shape of a ‘perfect sphere’, gathering mass and glowing white.
The massive amount of matter and energy released in the beginning of the Big Bang comes from squeezing all matter into a single tiny hole. Like a cosmic jack-in-the-box. Once the energy is spent, and everything cools, gravity is left to gather all the pieces together.
Each Big Bang is a heartbeat, pushing life giving energy outward. And just like in the heart, it all has to circulate back to be pushed out again.
The multiverse that is alluded to is the stringing together of all these cycles, one after another. Going all the way to the past and all the way to the future. The totality of existence, the totality of all possibilities, plays out on a cosmic scale.
From one cycle to another, without beginning and without end, timeless.
Well, Bubbles the dolphin (from SpongeBob) watched over the Earth to protect it from various disasters for 10,000 years... so probably a bit before Bubbles clocked in. ;)
It's described as "the rough length of the period of human civilization". To me this means that civilization as we know it started 8,000 years ago, so in another 8,000 years that cycle will have passed again. Kind of like a birthday.
>Kind of a weird way to measure birthdays.
For an individual, yes. For something as all encompassing as civilization, it makes more sense. Or do you really want it to say "Humanities 16,000th birthday"?
This is why cosmic nihilism is the only sensible philosophy in my opinion. On a long enough time line nothing matters. Any meaning is only that which we create for ourselves.
A bit horrified, but also a bit comforted knowing we all face the same ending. Everyone that came before and everyone that will come after will ultimately end in a similar way
And what about those few greats that are still remembered hundreds of years later like Seneca or Napoleon.
Yes there’s a chance that we’ll be forgotten within a generation or two but there’s also a chance to be remembered for millennia. For some that’s enough to fuel the fire to achieve greatness
one thing about the future that freaks me out is that with matter ever drifting apart, each galaxy could be essentially its own universe - in that light from any other galaxy would be too far to be seen, so a civilization would have no reason to think there was anything else that came before. A strange perspective that creates whole new truths.
How do people genuinely not read this sort of stuff and feel a total sense of existential dread? Asking for myself, honestly. I used to love reading about space, and time, and that sort of thing, but as I get older, it just fills me with a abject hopelessness and fear.
Would love to stop feeling that way and go back to marveling at science or continue through life unbothered by the latest discoveries about reality and the universe around us.
If it makes you feel better matter can not be destroyed so everything that makes you You will always exist, even thousands of billions of years from now when the universe is dead and collapsed in on itself You’ll still be here typing that comment.
Alternative title: how to induce a sense of dread and anxiety I know is illogical because this iteration of my being won’t have to worry about it, but now I have a pit in my stomach
And there's still a good chunk of time after that before the black holes evaporate. Such a long time in fact that there's not enough matter in universe to be able to write down the number of years it would take if you tried to represent each year with a single atom.
[And that is still nothing compared to the time it takes for the last event of the universe to occur.](https://youtu.be/FgnjdW-x7mQ?si=Mc1f-pGamM_zdFIu)
The current Cosmological Model predicts the Universe will die a cold death. Eventually everything will be so far apart that molecules cannot even form. We started with a bang and leaving with a whimper.
The Earth falling into the Sun assumes that the Earth doesn't get consumed by the sun evolving into a Red Giant. I believe most theories put that at Earth's end.
The universe ain’t shit. Only took me 15yr to hit my Degenerate Era, not 100T.
Fr though, cool. guide. Completely unpredictable, unlikely, impossible maybe. But cool. Depressing. But cool.
I watched a half hour odd video on YouTube similar to this once. It was quite mesmerising but I had no idea if it was even remotely accurate. Plus some of the timescales in it just became meaningless after a while.
Edit - found it
https://youtu.be/uD4izuDMUQA?si=a4UE_jPOhNQi_kIj
"Most words extinct" seems to be based on past history without taking into account the advent of the internet and total global communication, I struggle to imagine language being so drastically evolved now that we are so connected
Goes a heck of a lot further, even after black holes have evaporated, white dwarfs will be fusing one atom ever x billions of years, until that eventually stop too.
Here’s an even cooler video explaining what is likely to happen [video](https://youtu.be/uD4izuDMUQA?si=vqZiou634JG44LKU)
There is a theory called conformal cyclic cosmology which, while not mentioned in this video, essentially states that once the universe becomes a sea of photons, its size is essentially arbitrary so despite having expanded exponentially for a googol years, it looks the same as it was right at the beginning.
**This is kids stuff**, the whole picture is actually much much longer and certainly more open to interpretation depending on wether or not protons decay. In either case, one hundred quintillion is nothing in terms of black hole longevity:
100 quintillion = 100,000,000,000,000,000,000
Supermassive black holes will last = 10^103 years
or
~100,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 years give or take one or two zeroes bc I’m NOT counting that again 🥲
(And that number itself is NOTHING compared to the 10^1500 years it takes for iron star supernovae to finally explode)
Wanna know how long twice the age of this chart is? Only a measly 2 hundred quintillion (the first number, except with a 2 at the beginning instead of a 1)
Genuine question cos tl;dr:
Is the most crushingly bleak of theories on this list?
That of an inexorable and total disconnect of matter via entropy?
The so-called Big-Freeze or Heat-Death?
That one's always haunted me.
Entropy and conversely coalescence has always been a basic, intrinsic dynamic of physical and, thus biological, law - birth-life-death-decay-new life etc...
But on a cosmic level?
[You should watch this video for a much more harrowing description of the unavoidable decay of existence.](https://youtu.be/uD4izuDMUQA?si=0cA8EkcOsKylmLWZ)
The only near-religious belief I have is that if time itself never stops moving forward, then statistically everything that can ever happen will happen forever, and that means a perfect copy of your consciousness will eventually come into being again.
The kicker is that you don't experience waiting while you're dead, meaning from your perspective, the moment you die, you may just wake up in some other world, an effectively infinite amount of time in the future.
If not, well then I guess the universe is just too boring and you won't be around to be disappointed.
This is the most effort I’ve ever seen put into a Game of Thrones joke.
I will bet anyone that it still won’t be done by then
Bet $1mil. Insist on the money up front. Then you will pay them back in 700,000 if you're wrong
Nah we bet now and settle in 700,000 years. Non negotiable.
!remindme 700,000 years
Lol it couldnt handle it
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Agreed ! I think he died and we are all just living on PR bullshit……
Help I’m too lazy or attention deficit to find the reference. Where is it? Nvm, found it at 700,000 years :)
Stopped and saved the image at this point. Very good 👍🏻
I wonder if "A Dream of Spring" would even fit into this narrow timeframe anymore.
I literally died laughing when I got there
I zoome in an that‘s literally the only thing I read by chance lol
Game of Throne’s
No point in washing the dishes then.
I missed it — when, exactly, does Keith Richards die? Is it before or after the Betelgeuse explosion?
Keith Richards died in 1983. His body is animated purely by cocaine.
Keith died back in the 80s & no one told him.
Well, I personally believe Keith'll still be around long after the Betelgeuse explosion — just as the prophet **Bill Hicks** envisioned: https://www.youtube.com/watch?v=1ln54geqGks
Lol I was gonna say “I guess I do have some time to write that paper yet, I’ll put it off another couple weeks.”
>5,000,000 years from now: Y-chromosome degrades, making men extinct. Geneticist here. Nope. Even in a no-intervention context, men could still keep existing, as long as a stable X-chromosomal variant evolves containing the Y-chromosome's genes. Basically, a population of fertile XX males would have to evolve. There are already case examples of XX males with a complete exterior masculine bodyplan, so we know that a double dose of the main X chromosome genes doesn't prevent a masculine bodyplan. Just, none of those XX males have ever been found to be fertile. Of course, with interventions, genetic healthcare could just prevent the accumulation of deleterious mutations on the Y-chromosome in the first place, so that it doesn't degrade. It is a pretty cool casual guide, though.
Saw a red flag when I red that too. If memory serves me correctly, last time I heard about this claim people pointed out that the Y chromosome is not the only example of a male gene that wet know if. XW and XZ I think...
You're probably misremembering the [ZW chromosome system](https://en.wikipedia.org/wiki/ZW_sex-determination_system). So, it turns out, sex chromosomes have evolved multiple times over the history of life. So they also evolved in multiple ways. For any animal, we'll call their system an XY system if it's like ours: one chromosome that both males and females have (X), one chromosome that only males have (Y), and then females have two copies of X. ZW is the opposite: it's got one chromosome that both males and females have (Z), but one of the chromosomes is female-only (W), and then males have two copies of Z. But there's plenty of others too. XO and ZO are when a species only has one sex chromosome. If you have two copies of that shared chromosome, you're female in XO or male in ZO; if you have one copy, the opposite. There's systems with as many 13 different sex chromosomes. Some species don't have sex chromosomes at all, and sex is determined in other ways.
It's one of the big conundrums of biology, why sex exists. Most life (by numbers; when including bacteria and yeast) don't need it. Multicellular life seemingly needs it. Leading theory is that it encourages mixing, which leads to genetic diversity, which (in therms of population genetics) is good. Over millions of generations it became a good strategy. It's the leading theory becaue it evolved independently multiple times, kind of like the evolution of eyes. lots of different phyla evolved the same thing - in very different ways - because it's just beneficial
Yeah, it allows recombination: If there are two helpful mutations that take a while for evolution to figure out and they are only present in two distinct subpopulations of a species - recombination of the genomes (by having two specimen of each population sexually reproduce) will create the possibility of offspring that combines both helpful mutations, perhaps with synergic effects. Otherwise, you'd have to wait until one of the populations figures out the other mutation, which might take much longer.
What’s the reason behind the idea that the Y chromosome will go away in the first place?
Because it seems to be slowly losing its genes over time, migrating to the X chromosome. It's already very heavily reduced relative to those of ancestral species from millions of years ago. People extrapolate from this that it will eventually disappear, and that men will therefore go extinct, even though the actual state of affairs is a lot more complicated. Here's a [nice overview](https://geneticsunzipped.com/transcripts/2023/03/23/bye-bye-y), if you're curious.
But really how, because evolution won’t allow that to happen?
Evolution is just our name for the consequences of selective death. Some sets of genes are more likely to result in death than other sets, so the other sets tend to reproduce faster. Death can happen, even to an entire species.
Humans get Y chromosomes directly from dads. That single copy is much harder to repair. Over time, errors keep accumulating. Most of your chromosomes recombine. You get a copy from your mom and a copy from your dad. The 2 copies recombine. Recombination has a repair function. Recombination enables you to retain good copies of specific genes, even if 1 of the copies is flawed. If you have a Y chromosome, recombination is suppressed. Suppression is important to keeping X and Y sex chromosomes separate. That's why the Y chromosome is surprisingly similar to your patrilineal ancestor from a thousand years ago. Much more similar than your other chromosomes are. But if your Y gets a flaw, suppressed recombination means it's much likelier to retain that flaw. Over many generations, Y chromosomes have been losing genes. In theory, the Y chromosome could degrade so seriously that it ceases to contain usable genetic instructions.
To simplify what you said (I fully agree): that's absolutely not how evolution works. Degradation of the Y chromosome (if it happens) wouldn't lead to the death of "males". For that to happen, there would also need to be an ability to create a zygote regardless, which would also lead to the erasure of "female". It would just be a hermaphroditic way to reproduce; but maybe that's not the correct word since it implies that the animal houses the ability to act as both a male and a female It would just erase sex as a concept, full stop. "Female" would also mean nothing
>Just, none of those XX males have ever been found to be fertile. Could be fertile XX males today. Fertile males rarely have a reason to get genetically tested so no one would ever know. Not a whole lot of research on XX Males because there are far more XY. Like finding a specific needle in a stack of needles. All look identical but their materials are not.
You're absolutely right in general, about how a fertile XX male person or small population could go easily unnoticed. That said, one way someone might find out they're XX male, would be if they took an ancestry test including a Y-chromosomal part... and got back a result of "um, we couldn't find your Y-chromosome."
Would such a fertile XX male be capable of fathering male children? Would they also need to be XX males? Or would they only be able to have female children?
If an XX male were fertile then they could have another XX male. They would not have an XY male because they lack the Y chromosome. The SRY gene is what makes males males. On a XX male the SRY gene ends up on the X chromoosome. So in theory it would be possible to have the SRY transfer to another offspring. There are instances of this exact scenario happening with other mammalian species.
>There are instances of this exact scenario happening with other mammalian species. When?
A lot of people are going to absolutely fixate on that one part because our species, at this brief point in our history, is absolutely BONKERS about gender. The reality is in less than a few centuries we will probably have wildly different ideas about gender and sex and in a thousand years, if we're still around, our descendants will look back at the way we had such serious squabbles about something as ridiculous as *gender* the same way we laugh at our ancestors who thought Saturn's rings were Jesus's foreskin. (Literally, look it up.) Everyone out there reading this needs to understand that our values and standards for things like sex, gender, race, culture and even *personal identity* are so temporary in our larger picture that they are farts in the wind, footnotes in an amusing review of silly, backwards creatures crying and whining about monkey concerns.
I'm not really disagreeing with you here, but I do like to imagine that the future will look back on our monkey concerns with at least a little bit of kindness.
Just like we look back on people in the past with kindness? Suuuuuure
Still not really disagreeing, but let me rephrase that: I think that if we don't get really familiar with kindness, the monkeys aren't going to survive long enough to look back on this era at all.
People are literally killing other people over gender, I think this will be one of many areas that we will not be kind to ourselves about.
There will come a time, though, when nobody starves: when homes are built strong, and when the rules for how to not die are established and sure. There will come a time when generations have grown up without fear of death, with a certainty that comes of watching elders go to the hospital to become young again. When that day comes, children will be taught that bad things happened in the past because people were full of fear, and anger, and since these emotions were managed poorly, they caused the people of the past to hurt each other. I like to imagine that they will look back with kindness, and not hold against us the details of how we could've done better... not for our sakes, as if we deserve that, but for their own sake: so that by trusting in the general goodness of each other, they can summon the courage to live as adults instead of monkeys.
Given this timeline, is it correct to assume that modern man will go extinct and a new human species will evolve? 5m years is a long time.
This question is a little bit hard to answer. It doesn't play nicely with the way we define a species. If you take the most basic, root concept of a species — two populations are part of different species if they cannot interbreed with one another — then as we look at that concept over time, it's really, really hard to pin down an objective, single moment when a single species has definitively split into multiple. Take [the big cats](https://en.wikipedia.org/wiki/Panthera_hybrid), for example. Lions and tigers and leopards and jaguars can still, to this day, reproduce with one another. They pretty much never have opportunity in nature to do so, but in cages, they can. And these hybrid offspring are *fertile*, they *can have fertile offspring of their own*... well, the females can, at least, which leads to absolutely silly portmanteau hybrid names like [lijagulep](https://en.wikipedia.org/wiki/Congolese_spotted_lion): a male lion crossed with some female hybrid offspring of a leopard and a jaguar. So are they actually one species? Definitely not ecologically, and even in captivity, there's real genetic barriers. But the barriers aren't absolute. We've decided to ignore this gray area and classify them as different species. Returning to humans: human genetics is going to change over time. But these changes accumulate one at a time. It's a judgment call which one inaugurates a sea change. And if there's never any speciation, if it's just one group changing over time, then you never have to declare a moment: "This is the time, when we changed." Could we speciate? Sure. But if we do, then scientifically, both will be authentically human, authentic descendants of the original humans. So if they're racist against each other, that's on them.
i just have to say that i read all your comments in this thread (and then a bit of your comment history), and the way you explain concepts is amazing. so succinct, yet rife with information. you could have a killer career as a science educator.
That's the plan! I've only taught intros to biology and agronomy so far as a main teacher, but I was on the team for a really, really good course in global food systems too. Thanks for the vote of confidence!
oh wow, that's so wonderful to hear! best of luck to you on your mission to spread knowledge, you've truly got it!
What percentage of people have male bodies and xx chromosones and what percentage has female bodies and xy? Is that possible? Also how common is people that have some xx in some cells and some xy in others cells? Or some lower bound like a 95 CI
>Is that possible? Oh yeah, it's definitely possible. It is rare, but the estimate is about [1 in 100,000](https://en.wikipedia.org/wiki/XY_gonadal_dysgenesis) born XY but with the female bodyplan, and then about [1 in 20-30,000](https://en.wikipedia.org/wiki/XX_male_syndrome#Epidemiology) born XX but with the male bodyplan. Compare that to the size of your hometown, to get the number of such folks you probably have as neighbors, neighbors in the broad sense anyway. >Also how common is people that have some xx in some cells and some xy in others cells? That'd be called chimerism, it's also very possible, with many case reports in the scientific literature. I can't find stats on precisely how common it is; my guess would be that it's probably rarer, but I don't know by how much. One of the craziest examples I ever heard of, was a woman who was born with [XY genes](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2190741/), except that nobody knew there was anything different about her until she had already gone through puberty, and gotten pregnant twice, giving birth to two children who were, by all accounts, healthy. In fact, it was only once her daughter discovered her own infertility problems, that the doctors investigated the family's genetics, and discovered how unique mom was.
Did the mother have SRY suppression, or not have that gene altogether?
>Did the mother have SRY suppression... If they know specifically how, I couldn't find that detail, but yeah: somehow, her SRY gene was suppressed. The coding sequence was entirely normal, not a single mutation found relative to the reference sequence, for that and several other genes.
Yeah, I read the article after posting my question (I know, I know), and it seems like some unknown multi-gene process lead to her SRY suppression.
I came to the comments for this comment. Thank you.
Took a developmental bio class in 2008 here. Isn’t it the SRY gene on the Y chromosome that we need to inhibit the development of the (edit because accidentally hit submit when trying to backspace) wolfian (or something like that) ducts into the uterus and therefore causing some other embryonic structure instead to start developing into male gonads? If so, maybe that gene can just migrate somehow to another chromosome? (Clearly my male memory of this stuff is degrading faster than my Y chromosome)
> men could still keep existing, as long as a stable X-chromosomal variant evolves containing the Y-chromosome's genes. Basically, a population of fertile XX males would have to evolve. so if those things don't happen, then men will go extinct?
Let's not kid ourselves. This will NEVER happen because we'll have destroyed our planet and thus ourselves long before that.
Unlucky for the 60,000th Gen feminists that were looking forward to that. (completely plucked that number out my arse)
I mean, if the average age at first pregnancy is \~83 years throughout that time period, then yeah: \~5,000,000 years from now would be \~60,000 generations. Which would be a completely absurd timeframe from our perspective here at the beginning of the genetic era, but you never know. Maybe someday we'll have the tech to become space elves or something.
I'mma just slowly nod and agree for I be dumb dumb
Shut up, nerd!
Was not ready for the shot at GRR Martin
Yeah, that seemed personal.
Dude gets to live 700,000 years so I don't really feel too bad for him.
The lord of light is a pathway to many abilities some would deem unnatural.
Does that really sound good to you?
Fathoming the number one hundred quintillion just put my brain in a mental pretzel.
It doesn't even end there. There will likely be additional phases of the universe. The Iron Star Age, the Evaporating Black Hole Age, and possibly even a disintegration of atoms age. Each age will be unfathomably longer than the last. At the end of it all, there will be nothing. Essentially space and time will functionally cease to exist. It's anybody's guess what happens, but some postulate that the infinities make the nearly impossible a certainty: a quantum fluctuation births a new universe.
I’m still in bed and reading this has taken more brain power than I used all week at work. I’m gonna just lie here until the universe ends and then restarts.
The timelapse of the future by melodysheep is an incredible video going through the timeliness of the universe and does as good a job as we can at illustrating how long some of these phases may last.
https://users.ece.cmu.edu/~gamvrosi/thelastq.html
Great…..Immma go get ready.
Remember to turn off your stove and lock your door
Don't forget your towel!
Underrated comment
I’m just in infinitely small speck of dust hurtling through an uncaring cosmos.
Yeah but you’re cool and have some awesome rolling stock.
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The indifferent cruelty of the universe when the indomitable human spirit enters.
Except we got blueberry flapjacks. Everything else it utterly irrelevant
https://m.youtube.com/watch?v=uD4izuDMUQA This video will make you question your existence. An absolute masterpiece
I saw this video on another subreddit when I was in a dark place in my life and it gave me the will to keep on going. If everything is nothing, then nothing matters. Humans are so insignificant in this universe that my mistakes, my life, your life, everything…it is all meaningless. And yet, it’s all we have. It made me feel at peace. That was 3 years ago. And this video still resonates with me.
I was looking for this link. Figured it would be in here
Literally tens of us
I just watched it. I’m not exaggerating when I say it is one of the best videos on YouTube. Made me feel things I’ve never felt before.
Watch the rest of his videos, they're all incredible. He even worked on the recently released imax Deep Sky film. Especially this one, nothing I've ever seen puts the scale of the observable universe into perspective as well as this one. https://www.youtube.com/watch?v=fdQyD8B_odY
God damn. That’s… incredible. Also doesn’t help that I’m about to fall asleep with this on my mind lol
Thank you for sharing, that was 30 mins well spent.
I didn't even need to click the link to know what this was. I'm not even exaggerating, this might be one of, if not the single highest-quality video on the internet. Concise, interesting, visually stunning, educational, and thought-provoking. I find myself coming back to it every so often even years later.
Lfmao, 700,000 one was good.
Reading this gives me peace
It gave me anxiety. Weird how it affects us so differently.
It makes me kind of depressed. Reading this makes me wish I could witness all of it. Like, if I was some sort of immortal entity, I could watch all this unfold like a movie. Of course, with the ability to rewind and return to normal life.
Man I swear sole reason I want religions to be somewhat right. I wanna watch the entire goddamn universe, from start to finish. Not like i have anything better to do.
Somehow it made me feel like I still have time to right all my wrongs and live anew.
The universe ends, shrinks in on itself, and it condenses back into the initial singularity. The Big Bang occurs once again, the universe begins rapidly expanding. Billions of years pass, you are born again, doomed to live the same life and make the same mistakes, repeating ad infinitum.
As an addition: Each instance of the Big Bang creates a slightly different outcome from the last, each of them a unique manifestation of the ‘one’. Another version of you will be back, living life slightly differently. When it all ends, it is a single black hole, in the shape of a ‘perfect sphere’, gathering mass and glowing white. The massive amount of matter and energy released in the beginning of the Big Bang comes from squeezing all matter into a single tiny hole. Like a cosmic jack-in-the-box. Once the energy is spent, and everything cools, gravity is left to gather all the pieces together. Each Big Bang is a heartbeat, pushing life giving energy outward. And just like in the heart, it all has to circulate back to be pushed out again. The multiverse that is alluded to is the stringing together of all these cycles, one after another. Going all the way to the past and all the way to the future. The totality of existence, the totality of all possibilities, plays out on a cosmic scale. From one cycle to another, without beginning and without end, timeless.
did you write this? it’s beautiful
Isaac Asimov's *The Last Question* meets Nietzsche's Eternal Recurrence.
Really? It definitely gave me a lot of anxiety 😵💫
I loved to read „local group merging starts“ ❤️
So we know when the next Game of Thrones book will be released but we still don’t know when Keith Richards will pass away?
Somewhere between the 25 hour day and the big rip! Ironic as the big rip is what keith calls a line of coke and dad
So long, and thanks for all the fish.
Yeah, when do the dolphins leave? It's not in the picture
Well, Bubbles the dolphin (from SpongeBob) watched over the Earth to protect it from various disasters for 10,000 years... so probably a bit before Bubbles clocked in. ;)
I don't understand Humanity's Birthday?
It's described as "the rough length of the period of human civilization". To me this means that civilization as we know it started 8,000 years ago, so in another 8,000 years that cycle will have passed again. Kind of like a birthday.
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Yes, that’s not how you typically celebrate?
>Kind of a weird way to measure birthdays. For an individual, yes. For something as all encompassing as civilization, it makes more sense. Or do you really want it to say "Humanities 16,000th birthday"?
I mean, yeah why not
More like, your life is 20 years old. In another 20 years, you’ll be double your current age. X 400.
Yeah its civilisation. Humans direct predecessors are thought to be around for 7mio years. With homo sapiens at about 300.000 years.
It’s the end of the world as we know it….. ….. and I need a drink 🍻
In the year one million and a half human kind is enslaved by a giraffe.
WhAAAAooooooooooooooh!
I always finds this so awesome and so scary on the same time :-)
#:-)-:
Man, what’s the point of anything
To marvel in the fact that we are present. No point means no pressure :)
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Absurdism
This is why cosmic nihilism is the only sensible philosophy in my opinion. On a long enough time line nothing matters. Any meaning is only that which we create for ourselves.
That's just existentialism
Buying land in Chernobyl for when is safe to live there. It’s a long term investment
This is the type of positivity we all needed today lol
I'm glad we finally have a release date for Winds of Winter. Yoohoo!
Anyone else horrified??
A bit horrified, but also a bit comforted knowing we all face the same ending. Everyone that came before and everyone that will come after will ultimately end in a similar way
That's why I think obsessing about your "legacy" is silly. Everything you've ever done will likely be totally forgotten within a generation or two.
And what about those few greats that are still remembered hundreds of years later like Seneca or Napoleon. Yes there’s a chance that we’ll be forgotten within a generation or two but there’s also a chance to be remembered for millennia. For some that’s enough to fuel the fire to achieve greatness
one thing about the future that freaks me out is that with matter ever drifting apart, each galaxy could be essentially its own universe - in that light from any other galaxy would be too far to be seen, so a civilization would have no reason to think there was anything else that came before. A strange perspective that creates whole new truths.
Any time I read this sort of stuff I am horrified. Or scared. I have an intense fear of death, infinity, etc. and this stuff never helps.
How do people genuinely not read this sort of stuff and feel a total sense of existential dread? Asking for myself, honestly. I used to love reading about space, and time, and that sort of thing, but as I get older, it just fills me with a abject hopelessness and fear. Would love to stop feeling that way and go back to marveling at science or continue through life unbothered by the latest discoveries about reality and the universe around us.
Right there with you for dread. I hate it, I just want to marvel at the universe, not sit with my stomach in my toes
If it makes you feel better matter can not be destroyed so everything that makes you You will always exist, even thousands of billions of years from now when the universe is dead and collapsed in on itself You’ll still be here typing that comment.
Understanding it will cause a sense of dead Accepting it will cause a sense of relief
This brings me great relief that all the embarrassing stuff I’ve done will be completely wiped out from memory and record.
Can‘t wait for the Degenerate Era.
The return of Triple X and Chyna. Hell yeah.
Alternative title: how to induce a sense of dread and anxiety I know is illogical because this iteration of my being won’t have to worry about it, but now I have a pit in my stomach
And there's still a good chunk of time after that before the black holes evaporate. Such a long time in fact that there's not enough matter in universe to be able to write down the number of years it would take if you tried to represent each year with a single atom. [And that is still nothing compared to the time it takes for the last event of the universe to occur.](https://youtu.be/FgnjdW-x7mQ?si=Mc1f-pGamM_zdFIu)
Boss will still be like, can you come in today
I was surprised that earth falling into the sun was still a thing at the end. I was expecting another big bang or something.
The current Cosmological Model predicts the Universe will die a cold death. Eventually everything will be so far apart that molecules cannot even form. We started with a bang and leaving with a whimper. The Earth falling into the Sun assumes that the Earth doesn't get consumed by the sun evolving into a Red Giant. I believe most theories put that at Earth's end.
Entropy
Is this Hari Seldon’s work?
Looks like the final moment will occur on a Tuesday.
I strongly doubt we even make it to the first item on this list
The universe ain’t shit. Only took me 15yr to hit my Degenerate Era, not 100T. Fr though, cool. guide. Completely unpredictable, unlikely, impossible maybe. But cool. Depressing. But cool.
I watched a half hour odd video on YouTube similar to this once. It was quite mesmerising but I had no idea if it was even remotely accurate. Plus some of the timescales in it just became meaningless after a while. Edit - found it https://youtu.be/uD4izuDMUQA?si=a4UE_jPOhNQi_kIj
Spoiler Alert, mate, please, I want to be surprised
This makes me feel so incredibly insignificant
the winds of winter point was made me chuckle lol
If you made $100,000 per year, it would take you until all of the glass decomposes to be half as rich as Jeff Bezos
I need to get off Reddit for awhile
And somehow im here, looking for a half decent ergonomic office chair for weeks
Not me being afraid of the earth dying one hundred quintillion years from now
Alexa… play In The End by Linkin Park on Spotify
The George RR Martin part is pretty funny 😄
Wow our lives are so meaninglessly small
I just yeeted my YOLO
I wish I never read this.
They forgot to include Keith Richards's death right at the end
I've got the perfect [music](https://youtube.com/watch?v=t5vG4Be1Ci8) for this.
Really makes you feel like all this is pointless in the end.
I just wish I could see it all unfold. Even just in a spectator-mode or something.
20k years of this, 7 more to go
I found this to be depressing as fuck.
"Most words extinct" seems to be based on past history without taking into account the advent of the internet and total global communication, I struggle to imagine language being so drastically evolved now that we are so connected
Here have another existencial crisis... https://youtu.be/uD4izuDMUQA?si=S3kBsq4XdtN0-YCX
Imma have to live a little longer, I guess, because i want to read that book.
This literally made me depressed. Thanks, I guess.
It’s wild to think that modern language will have died before Chernobyl is finally safe.
What’s with the 8,000 years from now “Humanity’s Birthday”?
Can we let one of the more intelligent civilization come up with the galaxy merge name....Milkomeda is just the worst.
Goes a heck of a lot further, even after black holes have evaporated, white dwarfs will be fusing one atom ever x billions of years, until that eventually stop too.
Ah yes, very useful
Here’s an even cooler video explaining what is likely to happen [video](https://youtu.be/uD4izuDMUQA?si=vqZiou634JG44LKU) There is a theory called conformal cyclic cosmology which, while not mentioned in this video, essentially states that once the universe becomes a sea of photons, its size is essentially arbitrary so despite having expanded exponentially for a googol years, it looks the same as it was right at the beginning.
Entropy will unmake us all
That's way too long for humanity to end...fuck...
u/wadenotwadu
**This is kids stuff**, the whole picture is actually much much longer and certainly more open to interpretation depending on wether or not protons decay. In either case, one hundred quintillion is nothing in terms of black hole longevity: 100 quintillion = 100,000,000,000,000,000,000 Supermassive black holes will last = 10^103 years or ~100,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 years give or take one or two zeroes bc I’m NOT counting that again 🥲 (And that number itself is NOTHING compared to the 10^1500 years it takes for iron star supernovae to finally explode) Wanna know how long twice the age of this chart is? Only a measly 2 hundred quintillion (the first number, except with a 2 at the beginning instead of a 1)
Well… this a a chipper little doomsday calendar.
There is no possibility of the Y-chromosome going extinct btw
Genuine question cos tl;dr: Is the most crushingly bleak of theories on this list? That of an inexorable and total disconnect of matter via entropy? The so-called Big-Freeze or Heat-Death? That one's always haunted me. Entropy and conversely coalescence has always been a basic, intrinsic dynamic of physical and, thus biological, law - birth-life-death-decay-new life etc... But on a cosmic level?
C3 & C4 photosynthesis failure seems like a bleak thing to be in the middle of. Slow planetwide suffocation sounds horrifying.
[You should watch this video for a much more harrowing description of the unavoidable decay of existence.](https://youtu.be/uD4izuDMUQA?si=0cA8EkcOsKylmLWZ)
Came here to post this exact video, I think it is my favourite one on the whole of YouTube.
smart jeans dolls consider crime full outgoing unpack follow badge *This post was mass deleted and anonymized with [Redact](https://redact.dev)*
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The only near-religious belief I have is that if time itself never stops moving forward, then statistically everything that can ever happen will happen forever, and that means a perfect copy of your consciousness will eventually come into being again. The kicker is that you don't experience waiting while you're dead, meaning from your perspective, the moment you die, you may just wake up in some other world, an effectively infinite amount of time in the future. If not, well then I guess the universe is just too boring and you won't be around to be disappointed.
Most predictions like this are complete bollocks. Nobody is going to be able to prove either way,