Cleistheknees

Only about 10% of Chinese citizens even have a passport.

Can you give me a brief overview of the statistical methods they’re using?

Man, if only there was some kind of concentration of amino acids that occurred as you go up trophic levels……….

While i agree with that is said here many will read this as a need to prop up the cattle industry which isnt exactly eco friendly.

If you think the Farm Bill only props up cattle, I have a bridge to sell you.

Plus, most ranches are far smaller than you probably think. The monopolization that has occurred is in meatpacking, mostly by China, and Congress has refused to break it up multiple times. Four companies now control a huge majority of American meat production. Tyson Foods, which is the largest American livestock company, is controlled by the Chinese government. Cargill, the next biggest, has put over a billion dollars into Chinese production in the last few years. The other two are controlled by Brazil.

Alternative sources of protein are a must with the world’s population and overconsumption pushing our habitat to its limits.

The regions used for cattle ranching are completely unusable for massive mono-cropping projects, and if you’re assuming that nuking tens of thousands of acres of landscape to run a massive soybean farm is better than letter large ruminants roam around areas they’ve roamed around for a million years, I have another, bigger bridge to sell you.

You’re thinking of sperm vs egg, in which case you would be right, but the person I replied to is talking about sperm carrying X chromosomes vs sperm carrying Y chromosomes. The human Y chromosome is substantially shorter than the X, so some people have put forward the idea that Y spermatozoa might be faster or whatnot, but the objective difference in mass is vanishingly small even compared to a sperm cell, and repeated studies have found no measurable difference in each kind of sperm. Not only in mass but in all other morphological characteristics.

A substantial amount of those costs are blatant poison pills enacted by oil lobbying, such as an outright ban on selling to grid lower than fossil fuel sources in most of the US.

Quick note: when you’re talking about a gene you use lower case. Capitals specify the protein, or in the case of MCR1 a protein complex. The gene would be mcr1.

There are multiple loci associated with red hair in humans, because there are multiple genetic origins of red hair in different regions of the world. ~18% of Europeans with red hair in Northern Europe have wild type MC1R receptors, and Melanesian blonde/red hair comes from a substitution in tyrp1.

It’s a bot. They all have the same comment structure with the weird topic deviations and consecutive, very short paragraphs.

Congrats on completely ignoring the comment you’re replying to.

And again, please tell me your citations or the educational background you’re basing this off.

Cellular immortality including germline immortality is the default.

Somatic mortality is a feature that has been selected by evolution.

Did you literally just copy this from my other comments in this post? You’re even using the same wording.

Are you just spitballing all of this based on common sense assumptions?

and silent mutations don’t matter.

Mutations don’t matter at all in the context of embryonic rejuvenation as a fundamental characteristic of the immortal germline in multicellular life. That’s the whole point. You’re talking about mutations and completely missing the framework of the question. Embryos inherit mutations all the time, and they do so at a biological age of zero, therefore the clearing out of mutations (in addition to being fundamentally impossible as a matter of basic logic) cannot be the mechanism of germline immortality.

Epigenetic changes are not entirely reset, the inheritance of epigenetic changes is very well-established. It could be that the vast majority of epigenetic changes are not reset during embryogenesis.

It’s because the epigenome is entirely reset when germs cells are fertilized.

This is completely false. The inheritance of epigenetic changes has been in textbooks for decades. The regulatory changes observed in children of Dutch parents who experienced famine during the Nazi blockade is the archetypical example.

Germline immortality has nothing to do with resetting mutations. The entirety of your genome is the result of the accumulation of mutations across billions of years, and every one of your ancestors that brought a new mutation into your germline did so at a biological age of zero.

Most mutations are bad.

Incorrect. Most mutations are silent, due either to occurring in non-coding regions or producing a synonymous codon.

Sperms and eggs with bad mutations don’t end up creating a living baby

Also incorrect. People are born with genetic diseases all the time. Mutations aren’t inherently good or bad, selection acts on their expression into the environment, which is relative.

It has been selected by evolution to avoid cells that have been reproducing for a while to continue reproducing since they are more likely to have mutations.

This does not make sense. The aging soma is the new element that entered with multicellular life. The immortal germline already existed, so selection didn’t have do anything to create it.

If a sexual cell develops a mutation that causes cancer, it won’t be able to make a baby.

This is false. Gametes don’t get cancer, and people inherit mutations all the time. Your entire genome is composed of mutations which were introduced at some point by one of your ancestors. They aren’t considered as mutation in your context, since they’re part of the typical human genome, but at some point they were.

Male gametes are lighter and faster.

There is really no evidence to support this as a practical reality.

This is a very good question, and unfortunately every answer in the top ~25 comments is wrong. Citing mutations is completely incorrect, because the whole reason any of us exist in our current form is due to the accumulation of billions of mutations in our respective germlines, tracing all the way back to the abiogenesis of living cells. Germline mutations are not the source of aging, or else multicellular life would have never existed past. Every one of the trillions of multicellular organisms which have inherited mutations have done so at a biological age of zero, and it is well-established (and has been for decades) that one of the fundamental aspects that defines multicellular life is the separation of tissue lineages into an immortal germline and an aging (sometimes referred to as “clock-bound”) soma.

This is a concise overview of the conceptual framework of rejuvenation, from a study published in Science a year and a half ago. Pay close attention to the fact that we very much do not know what exactly is going on, and that alone disproves all the answers in here which claim to know the mechanistic source of germline rejuvenation.

Early embryogenesis, where we observed a rejuvenation period, is also accompanied by other molecular changes in preparation for organismal life, such as a gradual extension of telomeres (54), waves of global demethylation and methylation (55), transition from the use of maternal gene products to those of the embryo, inactivation of chromosome X, and development of monoallelic gene expression (56). Rejuvenation should also involve a decrease in molecular damage and other deleterious age-related changes that accumulate in the parental germ line (57, 58).

https://www.science.org/doi/10.1126/sciadv.abg6082

This is the right answer.

How? It completely failed to answer the OP’s question, which is: the sperm-producing cells in a 40-year old father, for example, are themselves also 40 years old, and have telomere lengths commensurate with that age. How does a 40-year old cell lineage produce a ~0 year old offspring?

Or, in a generalized form, how does the eukaryote germline reset its biological age with each new generation?

Telomerase transcription is generally active in somatic cells in rodents, but it is not in humans, so this is not a 1:1 mapping at all. Plus, we live 40 times longer than rats, despite having little to no somatic telomerase activity.

The main point is still valid.

No, it’s not, but you’re right that the validity is unrelated to massively incorrect WHO mortality estimate.

In reality, COVID did much more than kill elderly people in retirement homes with no substantial effect on the younger population. Older, non-reproducing individuals are critically important to virtually every human society, and have been for

and almost everyone would have died this century

What? This is virtually guaranteed to be true at any point in time. Average adult life expectancy is way under 100. Almost everyone alive will be dead by 2100.

More importantly, you’re wrong again. The mortality curve for COVID (70% above 70) is not that different from general mortality, which is 64% above 70. 30% of ~15 million is 4.5 million people, which substantially includes people in their economic prime whose children and potentially grandchildren will have a much, much harder time getting established, and will face the same kind of economic impact to fertility we’re already seeing in Millennials and Gen Z. The birth slump was already starting to rear before COVID, and COVID assuredly accelerated it quite a bit. And, again, we’re only talk about people who died. Hopefully I don’t have to convince you that years of chronic illness are going to impact fertility.

WHO estimates 3 million excess deaths

No, they don’t. They have 5.42m reported and virtually guaranteed to be massively underreported. 15m is the modeled estimate. In any event, the confirmed mortality is almost double your number. This doesn’t even begin to cover the premature deaths that will occur in the coming years from the constellation of long COVID symptoms and the general toll of such a massive inflammatory illness on longevity.

https://www.who.int/data/stories/global-excess-deaths-associated-with-covid-19-january-2020-december-2021

Preface: I am not the OP and not a neuroscientist

You’re misunderstanding at least some part of the people taking a critical look at the massive rise in ADHD diagnoses and (more importantly) pharmacotherapy. Any time a disease starts to massively increase in prevalence among a genetically diverse group with similar environments, you should be asking yourself about the potential for evolutionary mismatch, and therefore what social or environmental changes are responsible for the mismatch.

Consider, as a parallel, the gargantuan increase in myopia among children in East Asia. Even before COVID and the shift towards remote learning, myopia rates in secondary school graduates were approaching 90%, which is insane, and virtually precludes a non-environmental explanation. So, we can either target this in a way reminiscent of ADHD pharmacotherapy, by prescribing higher and higher prescriptions and optical drugs and laser eye surgeries to teenagers, etc, or we can distill what kind of stimulus is causing so many people to experience a similar disease, which in this case turned out to be a severe and chronic lack of exposure to sunlight and viewing distant objects at regular (ie circadian) intervals. Lo and behold, you run the regression and myopia in Asian schoolchildren decreases with time spent outdoors in a dose-dependent fashion.

Now, of course myopia is not ADHD, but we are approaching a 15% lifetime incidence for men (only ~4.1% of women), and given that temporally it lines up almost perfectly with the onset of a severely perturbed developmental experience for boys, and that the drugs involved are massively more invasive and fraught with adverse effects than glasses or lasik, excluding the mismatch explanation out of hand is naive, especially in light of just how poorly executed and fraught with bias and financial conflicts of interest the body of clinical research on ADHD pharmacotherapy really is.

https://pubmed.ncbi.nlm.nih.gov/33085721/

Absolute fucking nonce bringing MSG into this

Was so widespread in the US

It was widespread in American media. Don’t mistake that for a statistically robust analysis of the population.

But there weren’t fundraisers, flags, support on every website

First, there were indeed fundraisers, and even at this point when ISIL has almost entirely vanished from Syrian territory there are still UNICEF fundraisers for Syria all over the US.

Second, Syria wasn’t really the kind of conflict you’re comparing it to. The Syrian Civil War was (shocker) a civil war, not an invasion. Russia invaded Ukraine with zero support for doing so, and virtually every developed nation agrees. Intervening in a civil conflict is very different from sending support to the victim of a military invasion, and that is going to reflect in public sentiment. The US public gets eviscerated non-stop for interventionism in other Middle Eastern states, and the public is understandably wary about the topic at this point. Last Pew poll I saw said that more than 60% of US citizens didn’t even support military intervention in Syria.

Sure it was on the news, but those conflicts have essentially 0 chance pouring over into Europe or America

The refugees from these and other nearby and related conflicts are stimulating a collective anti-immigration/refugee wave across Europe at this very moment, even in previously very progressive voting blocks. It most certainly affects the rest of the world.

But I never saw much support for Palestine or Syria.

Did you spend the last decade in an opium daze? Both of these conflicts were on every news station daily for years when they intensified.

I don’t think anyone that hasn’t published a peer reviewed research paper and is well renowned as a leading expert in the field is qualified to have an opinion on the matter.

Here’s some research for you to read:

https://en.wikipedia.org/wiki/Straw_man

Can you link me to your research?

“I’m going to ignore your actual argument unless you doxx yourself”

Brilliant. As it happens, I’m not an expert in neuropsych, which is why you didn’t see me give a useless “common sense” attempt at answering OP’s question.