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How the placenta evolved from an ancient virus (2020)

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Re: How the placenta evolved from an ancient virus (2020)

#41

Post by nostrademons »

jmyeet wrote: post #28
mlcrypto wrote: post #14

Kinda morbid thinking about all the failed mutations as laying eggs evolved into the placenta

Here's another sobering thought: you represent an unbroken chain from the universal common ancestor of successful reproduction going back billions of years and probably trillions of generations (given that many of those were as a single-celled organism). Every one of those generations a success. So if you fail to reproduce you will break that billion year old chain of evolutionary success. Here's another: you have 2…

I suspect a lot of the "woe, things are way harder for Millennials than past generations, I'm too poor to have a family" zeitgeist is actually this phenomena + literal survivorship bias. Every single person alive today came from parents that successfully reproduced. When you're a kid, it's very natural to think that having kids and a family of your own is the default state of being. After all, all of your friends have parents who successfully reproduced too.

But that's because you tend to have much closer relationships with your family and peers than with childless adults. When I change my sample from "my friends growing up" to "my parent's friends when they were growing up", a lot of them never had children. By the numbers, the percentage of households that are families with children has gone down, but it's gone from about 55% in 1970 to 40% in 2022, which is a much less drastic fall than most people would suspect. Being childless is far more normal than children believe.

Re: How the placenta evolved from an ancient virus (2020)

#43

Post by qup »

vlovich123 wrote: post #34
ta8645 wrote: post #19

Earlier quoted context omitted.

You're really missing the point -- there's no way to know the future. Maybe your optimism is warranted, but maybe we stamped out a virus that would have given us a superpower. The argument is _not_ that we should change our strategy of doing the best we can with the information we have. Just that we should have some humility about what we can and can't actually predict, or say with certainty.

Our superpower is developing technology. It’s unlikely evolution could ever outperform that as it operates on much slower time scales for adaptation. So any viral mutation now will only really manifest at population scale after hundreds of thousands of years whereas technology can do it within years or decades.

Additionally, the tech level will eventually allow us to discover and implement any/all available superpowers.

Re: How the placenta evolved from an ancient virus (2020)

#44

Post by dirtyhippiefree »

Think about it.

The species that is now Mitochondria was an entirely different species.

We carry Mitochondrial DNA, while the human side is Nuclear DNA…nucleus of every cell.

Birth as we know it wouldn’t have happened without a third species invading our cells. We know it as placenta.

Profound that we fight microbes, but without two (that we know about), our species literally (accurate use) would not exist.

At all.

Just, wow.

Re: How the placenta evolved from an ancient virus (2020)

#45

Post by [deleted] »

jmyeet wrote: post #28
mlcrypto wrote: post #14

Kinda morbid thinking about all the failed mutations as laying eggs evolved into the placenta

Here's another sobering thought: you represent an unbroken chain from the universal common ancestor of successful reproduction going back billions of years and probably trillions of generations (given that many of those were as a single-celled organism). Every one of those generations a success. So if you fail to reproduce you will break that billion year old chain of evolutionary success. Here's another: you have 2…

[deleted]

Re: How the placenta evolved from an ancient virus (2020)

#46

Post by ta8645 »

vlovich123 wrote: post #40
ta8645 wrote: post #39

Earlier quoted context omitted.

You're doing a lot of work to continue to miss the point. The point is not that we should embrace viruses in order to reap the benefits. Just that it is _POSSIBLE_ that a virus would turn out to be very beneficial to humanity, in the long run. We know this to be a fact, because of the article we're reading above. The only point I'm hoping people will take, is that we shouldn't be so quick to make categorical statemen…

No, you’re assuming a counterfactual that isn’t necessarily true. If the virus hadn’t come along, humanity as it stands today may not exist but whatever animal was infected could potentially have kept reproducing / another virus would accomplish what happened anyway. Those are far more likely scenarios. You’re taking an impossible to prove hypothetical that would require omniscient level reasoning and predictive powe…

> No, you’re assuming a counterfactual.

I'm not assuming anything. I'm following the science as reported in the article above. That in FACT a virus lead to an important part of human development. And was in FACT beneficial. Those are true facts, if you trust the science.

> If the virus hadn’t come along, humanity as it stands today may not exist but whatever animal was infected could potentially have kept reproducing / another virus would accomplish what happened anyway. Those are far more likely scenarios.

You literally immediately launched into assuming a counterfactual (that didn't happen, you just made it up).

> You’re taking an impossible to prove hypothetical that would require omniscient level reasoning

Yes, and I made it clear that's what I was doing. And I explicitly said it was an imaginary situation that would never happen. I was using it for illustrative purposes for people who are flexible enough in their thinking. I'm sorry that isn't you.

Re: How the placenta evolved from an ancient virus (2020)

#47

Post by TravisCooper »

zakki wrote: post #22

If every part of a human coming from evolution, how it synchronize between each part? Is there any books explaining evolution in detail? How cell formed? How they found a way to multiply? How they choose DNA to store the information? And so on.

[flagged]

Re: How the placenta evolved from an ancient virus (2020)

#48

Post by wruza »

jmyeet wrote: post #28
mlcrypto wrote: post #14

Kinda morbid thinking about all the failed mutations as laying eggs evolved into the placenta

Here's another sobering thought: you represent an unbroken chain from the universal common ancestor of successful reproduction going back billions of years and probably trillions of generations (given that many of those were as a single-celled organism). Every one of those generations a success. So if you fail to reproduce you will break that billion year old chain of evolutionary success. Here's another: you have 2…

So if you fail to reproduce you will break that billion year old chain of evolutionary success.

True to an extent. What you really break in this case is the last inch change that your parents happened to merge in. Your extended families are still there with almost the same genotype.

Re: How the placenta evolved from an ancient virus (2020)

#49

Post by lo_zamoyski »

vlovich123 wrote: post #32
jmyeet wrote: post #28

Earlier quoted context omitted.

Here's another sobering thought: you represent an unbroken chain from the universal common ancestor of successful reproduction going back billions of years and probably trillions of generations (given that many of those were as a single-celled organism). Every one of those generations a success. So if you fail to reproduce you will break that billion year old chain of evolutionary success. Here's another: you have 2…

Humans are social animals. It’s myopic I think to only evaluate based on reproduction and genetic propagation. For example, most bees and ants are not involved in reproduction but they are all involved in helping the species survive into the future. So even if you don’t reproduce you have a critical role to play in society (helping it stay cohesive, helping productivity, helping through your work efforts, helping you…

The OP was making an observation. But I'll bite.

First, human beings are not bees or ants. Our nature vis-a-vis reproduction is quite different. Most human beings do reproduce as that is our nature, or certainly most of us used to with the exception of periods of social collapse (think of Rome). We're in that sort of condition now, where we are having little or no children in the developed world. This does not bode well and at some point the decline of such a society will become irreversible.

Of course, you are right that not everyone must reproduce, that there is no particular obligation for anyone to reproduce, and that those who do not can still contribute to the well-being of their families, the human species, and the common good. And indeed, if you are, say, a Catholic, you would say that while having children is the natural course and the normal path for most people, a small minority are called to sacrifice this natural end for the sake of a higher supernatural, spiritual end, e.g., the priesthood, by which one becomes a spiritual parent in place of a biological one. Certainly, we can be parental figures in non-biological ways as well. Even biological parents do that.

But that's not that we're seeing behind the present demographic decline. Something like the priesthood is an exception, not the rule. Most who can have children of their own are not having them, or many of them, not because of some kind of exceptional higher calling, but rather for morally dubious reasons. Children are demanding. They require sacrifice. They demand the love known as charity. A consumerist is going to view a child not as a gift, but a burden. Furthermore, our society demonizes families, especially large families (perhaps in part stemming from Protestant attempts to restrict Catholic populations in the US). Having many children used to be seen as a blessing, a privilege. Today, we both think we're entitled to having children (IVF is a testament to that), and refuse to have them.

Re: How the placenta evolved from an ancient virus (2020)

#50

Post by mrphoebs »

vlovich123 wrote: post #37
mrphoebs wrote: post #35

Earlier quoted context omitted.

I doesn't seem like the above commenter was making a value judgement.

> So if you fail to reproduce you will break that billion year old chain of evolutionary success. I’m responding to this and saying that’s not an accurate way to frame it. I’m saying you are participating in evolutionary success even if you don’t reproduce. For example, a more social family where there are siblings that don’t reproduce and instead invest in the success of the reproductive sibling’s offspring is still…

My mistake, I presumed incorrectly, that the argument you were making came from a place of defensiveness, rather than a more holistic framing of evolutionary success. Thanks for providing further clarity.
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