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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)

#101

Post by pfdietz »

MrVandemar wrote: post #91
TravisCooper wrote: post #55

Earlier quoted context omitted.

Strange that an uncoordinated, random walk of mutations would keep a profound number of changes in tact, ready for some other random bit to take place and it all just "fall into place". The eye didn't evolve. Hearing didn't evolve. Smell didn't evolve. This line of thinking is just hopeful projections of desired causality.

> The eye didn't evolve. Hearing didn't evolve. Smell didn't evolve. I don't know if you're being somehow pedantic for some definition of "eye" or "evolve", or if you're one of those "Intelligent Design" creeps.

I think people are misled because it's difficult to really grasp the very high dimensionality of the space ("morphospace") in which organisms sit. There are many, many directions for incremental change to go in, and evolution just needs there to be an improving step at each point along the path. In a low dimensional space it would be easy to get stuck in local minima, but as the number of dimensions increases that's harder and harder.

Evolution can be very easy given time. Trees independently evolved from non-tree plants something like 100 times, for example.

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

#102

Post by Sprocklem »

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'm not sure how exactly the circulatory system developed in our ancestors, but I will add that simpler circulatory systems do exist in animals today, including the open circulatory systems that are found in, e.g., arthropods. In these animals, blood is pumped across an body cavity by a heart, before flowing back through the fluid-filled body cavity itself, outside of any blood vessels. It is definitely possible to have "partial" circulatory system that functions fine while lacking some of the components present in humans.

Similarly, simpler versions of, e.g, eyes have been observed in nature with structures that are thought to be analogous to those of our early ancestors when eyes were first developing.

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

#103

Post by pfdietz »

mlcrypto wrote: post #14

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

There's a reason religious types recoiled from Darwin's idea. It paints God as a vivisectionist on the grandest scale.

Darwin experienced this as a father, watching his oldest child die slowly and horribly (probably from cerebral tuberculosis). It would not be a stretch to imagine this experience soured him on traditional religious dogmas.

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

#104

Post by theGnuMe »

ta8645 wrote: post #19
boredgargoyle wrote: post #7

Earlier quoted context omitted.

There are probably thousands (and my guess would be much more) viruses that that dance on the information playground that is our genome, metagenome, and the genomes of the organisms we host. Fighting a few of them is probably not going to be a significant issue. Having more individuals around by itself would also lead to mutations which the environment may select for in the future. By itself there is no such thing as…

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.

Super powers would be sensory I think unless we sprout wings or gills. So things we've probably seen already in another species like infrared vision or what not... but we do have technology to do that already so the question is how does that influence the evolutionary landscape.

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

#105

Post by [deleted] »

pfdietz wrote: post #103
mlcrypto wrote: post #14

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

There's a reason religious types recoiled from Darwin's idea. It paints God as a vivisectionist on the grandest scale. Darwin experienced this as a father, watching his oldest child die slowly and horribly (probably from cerebral tuberculosis). It would not be a stretch to imagine this experience soured him on traditional religious dogmas.

[deleted]

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

#106

Post by pi-e-sigma »

lynguist wrote: post #100
derac wrote: post #74

Earlier quoted context omitted.

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

And 30% to a tomato. So what? The basics of cellular respiration are always the same on this planet.

https://en.wikipedia.org/wiki/Sulfate-reducing_microorganism

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

#107

Post by ceejayoz »

zakki wrote: post #88
deadbeeves wrote: post #75

Earlier quoted context omitted.

>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…

> If the life formed by randomness, according to this old Discovery video[1], it defies law of probability.

Evolution is not random. The mutations that make it possible are, but natural selection makes it a non-random process.

If you make a random number generator, but keep more of the odd numbers, you'll get a non-random result set.

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

#108

Post by BurningFrog »

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.

That's a different kind of percentage. The terminology is unfortunate and confusing.

I'm taking about the sense in which you share 50% of the DNA with a sibling or payment.

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

#109

Post by deadbeeves »

zakki wrote: post #88
deadbeeves wrote: post #75

Earlier quoted context omitted.

>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…

There are crappy combination padlocks that can be picked by turning the combination wheels and pulling on the shackle. When you've turned a wheel into its unlocking position the shackle will shift open slightly, signalling that you've cracked that digit. So a padlock with 3 digits could be opened in at most 30 moves, instead of 1000.

When you have a selection mechanism, the randomness of mutations becomes kind of moot. Each step of the way that produces a new adaptation only has a handful of optimal (or optimal-enough) solutions. Now, suppose that we're an underwater species that's in the process of developing light-sensitive cells, and from our present genome there are 2^64 possible genes that will produce a good protein for the transduction step (of converting light into some other form of energy). Do we need to mutate 2^64 times to find the "correct" gene? No, all of those 2^64 genes are "correct". Our descendants should not fall into the trap of thinking that because they got gene #5541741487894936799 that it was a special outcome. They could have just as easily gotten gene #5541741556614413535.

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

#110

Post by vlovich123 »

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.

The person making the claim gets to present the data supporting it.

It depends on what you mean by collapse. Is it that population will decline globally for a bit to a new equilibrium point? Sure I can believe that because boomers were a huge population bubble after WWII and there have been lots of living standard advancements since then (a huge one being family planning options being more and more available to the world’s population). It’s also important to remember that the population bubble was also driven by significant life extension and health advancements in medicine and nutrition without any real birth control being available so the lag until birth control became available results in another population bubble.

None of that is particularly dire. And btw, it’s not even clear to me that the population will actually start decreasing. And even if it does, believing it’s some runaway effect that can’t be fixed within 20 years once we notice it seems myopic as well.

The position you’re taking though, that population will not only decline but that there’s no bottom to it and society will collapse, is the Elon Musk doomer talking point that this somehow portends the end of countries or civilizations or humanity itself. There’s simply no evidence and no realistic mechanism of action for something that extreme. Human populations have always ebbed and flowed and the exponential growth we’ve seen since the Industrial Revolution is not the norm nor is it sustainable.

> 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

Again - you’ve stated something quite extreme without providing any support and then tried to shift the responsibility for providing evidence to the person doubting your wild claim. That’s not how it works, sorry. It is a hypothesis that there’s demographic collapse until it’s either happened or there’s credible evidence it will happen. Right now afaik neither is true.

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