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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)

#81

Post by tanepiper »

safety1st wrote: post #72
lo_zamoyski wrote: post #49

Earlier quoted context omitted.

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 w…

I'm downvoting this because of the arrogant and dubious notion that people who've chosen not to have children are somehow morally flawed. The fact of the matter is that successfully raising, educating etc. a child is dramatically more expensive than it was a few generations ago. While we can debate the various reasons for the decline in the reproduction rate there's no doubt that this is a big one, not as many people…

It's not just economics. I earn a good salary and own my house, but I'm on my second marriage as both my partner and I have ADHD and Autism and in our 40s.

It's not fair to try raise a child in those conditions, so we choose not to for their sake more than ours.

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

#82

Post by NortySpock »

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…

I'm currently more focused on spreading good memes to the next generation.

Memes like kindness, empathy, planning ahead, being honest with yourself (and preferably others), communicating your intentions clearly ahead of time, and how good parenting takes more emotional labor and emotional intelligence than, say, the kind of parenting that solely consists of yelling when the parent does not receive the desired response from the child.

Genes are not the only thing the next generation needs.

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

#83

Post by inciampati »

derac wrote: post #74
BurningFrog wrote: post #60

Earlier quoted context omitted.

Ants and bees in a hive have very similar genetics. Typically 75%, and sometimes 100%, if I remember. This means that a hive in some ways is best thought of as a single organization, which happens to have a "distributed" body. In that view, the non reproducing individuals are propagating their DNA in the same sense that human liver cells do, even though they don't have the direct involvement that down and egg cells d…

Human beings are 99.9% genetically similar to each other. Also, we're about 99% genetically similar to chimpanzees.

In the euchromatic regions, yeah, it's about that. Elsewhere (e.g. centromeres) we are all quite diverse. This is recent news due to long read sequencing and complete genome assembly. The human pangenome project is touching on this, if still reticent to make clear claims about the centromeres.

I'm not sure that "99%" similar is the right way to think about chimpanzees and humans. We have a different chromosome number. Our chromosome 2 is a roberstonian fusion of two acrocentric chromosomes found in all other great apes, including chimpanzees and bonobos.

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

#84

Post by overtomanu »

zpeti wrote: post #63
vlovich123 wrote: post #58

Earlier quoted context omitted.

No humans aren’t bees or ants. We’re social animals and you can’t ignore society and culture as aspects of evolution. Regardless, you’ve taken this whole thing in a weird direction bringing up a demographic collapse that is a fringe theory at the moment. As for that hypothesis, there’s no actual indication that humanity is in any danger of a collapse just because the boomer generation is passing and our numbers retur…

> demographic collapse that is a fringe theory at the moment Show me the actual numbers where this isn't a massive change in humanity in the future? This is not a fringe theory. The effects of the collapse we can theorise on, but the collapse will happen now. It's not a question or a theory.

My theory is that, as of now population might be above a "equilibrium". Since it is above equilibrium, it causes increased economic competition to raise kids. So only few economically well off couple have kid's.

After few generations, population comes back to some level where economic competition to raise kids is reduced. Also, most of the lineages of people who chose not to have kids would have been wiped out or atleast somewhat reduced (Natural selection at play). So the people living in the future are likely to have kids on the condition that there is no economic penalty.

So humanity extinction due to demographic decline is less likely. Instead it might happen due to something like nuclear war. More details: https://en.wikipedia.org/wiki/Fermi_paradox#It_is_the_nature...

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

#85

Post by _0ffh »

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…

Here's another, superficially quite perplexing one: Your female ancestors vastly outnumber your male ancestors.

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

#86

Post by overtomanu »

_0ffh wrote: post #85
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…

Here's another, superficially quite perplexing one: Your female ancestors vastly outnumber your male ancestors.

For those wondering, I think this is mostly because of men having multiple wives.

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

#87

Post by overtomanu »

TravisCooper wrote: post #47
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]

You can take evolution of eye for example, see https://en.wikipedia.org/wiki/Evolution_of_the_eye

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

#88

Post by zakki »

deadbeeves wrote: post #75
TravisCooper wrote: post #69

Earlier quoted context omitted.

>An appeal to incredulity is not an argument. It IS strange, using the evolutionary framework itself, that useless mutations will hang around for thousands or millions of years (countless generations) before dropping perfectly into an extremely complex system, that itself is but a small part of a larger complex system. Evolution teaches that small, immediately useful mutations build upon one another, reinforcing the…

>They're each extremely complex Yes. Now . Not when they first emerged. >but useless without the other two Unsubstantiated assertion. >How would evolution slowly build a heart with no blood or blood vessels? How would evolution slowly build blood but no blood vessels or heart? How would evolution slowly build a network of blood vessels but no blood to carry or heart to pump? You start with a fluid-filled body cavity…

I guess I can see where the parent thinking you replied came from. If the life formed by randomness, according to this old Discovery video[1], it defies law of probability.

If each step from simple to complexity is using this randomness evolution, it will be more and more defies law of probability.

Wikipedia said earth had water 4.4B year ago. The first cell formed 3.8B years ago. This PBS video[2] said multicellular life emerged 1B years ago. Other source said 1.7B years ago. And then the first modern human appeared around 300 thousands years ago. So the question is: is 700M-1400M years enough time for the probability to create human?

[1] https://youtu.be/z2_-h3I_WXQ

[2] https://youtu.be/0TgKW-dj-wo

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

#89

Post by safety1st »

eks391 wrote: post #80
safety1st wrote: post #72

Earlier quoted context omitted.

I'm downvoting this because of the arrogant and dubious notion that people who've chosen not to have children are somehow morally flawed. The fact of the matter is that successfully raising, educating etc. a child is dramatically more expensive than it was a few generations ago. While we can debate the various reasons for the decline in the reproduction rate there's no doubt that this is a big one, not as many people…

I don't believe whether ones finances allowing someone to have children is the factor for whether they will. From my observation (i have not researched this; this is anecdotal), wealthier people opt to have fewer or no kids, and larger families are usually those of lower income, like there's an inverse relationship between wealth and desired number of children. Even I used to want a large family until I acquired a hi…

There used to be some truth to that but not so much anymore. It's historically correct that the poor used to have more kids (and I think are still a bit more likely to have them than the middle class). But what started to happen about 10-15 years ago was that everyone became less likely to start a family except for rich people. To be precise if a woman is rich enough to afford childcare she's much more likely to have kids.

Here's an article on the topic: https://www.theguardian.com/lifeandstyle/2014/oct/25/women-w... - that's about a decade old and the evidence/trend has only grown.

Children are just another one of those things that is increasingly out of reach for the American middle class, along with property ownership, health care etc. For the poster I responded to to ignore the economic data and paint the middle class and ordinary human beings as being selfish and immoral is perverse.

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

#90

Post by Dalewyn »

eks391 wrote: post #80
safety1st wrote: post #72

Earlier quoted context omitted.

I'm downvoting this because of the arrogant and dubious notion that people who've chosen not to have children are somehow morally flawed. The fact of the matter is that successfully raising, educating etc. a child is dramatically more expensive than it was a few generations ago. While we can debate the various reasons for the decline in the reproduction rate there's no doubt that this is a big one, not as many people…

I don't believe whether ones finances allowing someone to have children is the factor for whether they will. From my observation (i have not researched this; this is anecdotal), wealthier people opt to have fewer or no kids, and larger families are usually those of lower income, like there's an inverse relationship between wealth and desired number of children. Even I used to want a large family until I acquired a hi…

>wealthier people opt to have fewer or no kids, and larger families are usually those of lower income, like there's an inverse relationship between wealth and desired number of children.

I've also noticed this trend, richer societies have less children and poorer societies have more children.

Absolutely no politician (aka the people charged with population and demographic concerns) actually points this out, though. Probably because it goes against a lot of narratives and the simple solution it implies is brutally unpalatable for pretty much everyone.

I also notice that every single would-be or could-be parent inquired says they can't afford it, while also clearly enjoying many luxuries that being poor would actively prohibit. I presume they all keep claiming the issue is money because who doesn't like free handouts from the government just by saying you'll have kids? Get 'em while the getting's good. I'm not talking about just the US, either.

Anyway, I believe the only true solution to declining birth rates is simply to become poor again as a society. It's the only logical solution when becoming richer clearly leads to less children.

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