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CharonY

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Everything posted by CharonY

  1. If I remember correctly the issue is that cotton actually does retain water rather well. Once wet, they do not provide thermal insulation. In contrast, contrast, wool can wick moisture due to capillary actions fairly well. Also, hydrophobic materials do actually work well as undergarments- a lot of thermal underwear is made with synthetic and synthetic mixes. I think one of the things we were told was to slowly warm up persons, starting with the core (not the extremities, due to the reasons you mentioned).
  2. You are not my boss, you cannot tell me what to do! I think most good ways to maintain temperature are actually the obvious ones (wear layers, cover exposed skin, shelter from wind, etc.). Many others things offer temporary relief, but once we are past the -20C (and wind chill!) things get rather complicated (or easy, depending on perspective).
  3. In addition, carbon production is a decent indicator of resource use, which in turn in related to things like habitat loss. Moreover, often habitats are not destroyed to fulfil the immediate needs of the local population, but in order to produce goods and food items for rich countries. The average US-American consumes 20 times the amount of meat as the average Ethiopian. So following this logic The most effective way is to abolish lifestyle and reduce populations of affluent nations first.
  4. Often these arguments are just a poor excuse not to do anything. E.g. the thought that any reduction of emissions is meaningless, as China is producing so much. Often sprinkled with bigoted sentiments (we are not the problem, those folks are). Thereby we are repeatedly shooting ourselves in the foot in an effort to sit an on an issue up until we are forced to do something. Seems to the modus operandi for a lot of population-wide issues, including the pandemic, for example.
  5. Missing a bus and waiting for ~30 mins at around -35 C was fairly unpleasant.
  6. That does not work. DNA/RNA does not provide information on the cellular environment as such. I.e. you cannot use genetic information to create cells. You will have to start with whole cells to begin with (if we want to ignore some sci-fi element that makes it magically possible that is).
  7. A few things here: as TheVat mentioned, birth control is not the sole issue, improving standard of living is one of the drivers of reduced birth rates. Also, the number of people will continue to increase due to demographic momentum. The only way to reduce the number of folks is to actually kill people off. And also the focus on population alone is very misleading. Countries that have positive population growth tend to use much fewer resources than their counterparts with declining or stabilizing populations. Each Canadian has the CO2 footprint of about 200 Somalians, for example. Sorry to hear that it happened to you, too. Now talking to folks from way back, these types of gaslighting were shockingly common. There is a bit of a momentum in various health system to combat that, but despite improvements, there are still rather horrific cases out there.
  8. I think this looks like extra privilege as it lacks the added context why it is important to show being inclusive. The issue is that studies have shown that in many countries the health system underservices minority patients. Especially, but not limited to indigenous persons. These issues also overlap with socio-economic factors so by paying that extra care the hope is to raise the level of health outcomes to at least something approaching that of majority patients. If we are talking about anecdotes, I have somethin to share specifically in that area. When my father fell ill and was extreme pain he was diagnosed with home sickness and the MD told him that he just wants to get back to his home country. While he narrowly avoided losing the use of his legs, and he managed to continue working until retirement, he is in constant pain. The disease itself is easily diagnosed if just the same level of care had been given as to a majority patient. Also, it was not just one MD. After the first made his ridiculous diagnosis it was impossible to get a dissenting second opinion. Now, this was quite a long time ago, but these attitudes were extremely prevalent. So the course correction you mentioned there is not extra privilege. It is a countermeasure to be being treated extra-shitty.
  9. There is even more to it. You need basically a kind of cellular environment for it to its proper thing. You can (to some extent) throw together RNA, ribosomes, enzymes, amino acids and the proper buffer together to produce proteins, but those would not do much. They need other proteins, all kind of metabolites membranes etc. to sustain function. So it is exactly right that we actually need functional cells to actually do something.
  10. Absolutely. The problem with these types of questions is that they are very difficult to test. Therefore, narratives alone are pretty much worthless, which is why folks advocating thermoregulation created some models to check whether they make sense (and there has been some back and forth). But as always, the situation is highly multifactorial and a lot of things can play a role, including stochastic effects (e.g. drift) or something that occurred during that time, but for which we won't find any fossil evidence for. For example, one could speculate that at some point there was some extremely severe skin disease or parasite where somehow loss of functional hair provided a benefit. We cannot prove it either way, but clearly it does require some level of substantiation. Similarly, sexual selection has been mentioned by some, but as these also do not leave records, it is not a terrible useful model.
  11. So based on your hypothesis, the orangutans who are able to shield themselves form rain would soon be naked? Each species history is unique and comparisons would only make sense if we find equivalency in critical aspects. One argument for heat sensitivity of humans is that the human brain is quite large and is very sensitive to overheating. Quite a few animals have for example a carotid rete, which helps cooling the brain especially during bursts of activity. We don't have that, for example. And I will again point to folks living in savannas who often only cover their lower body parts and somehow are still alive. Many animals in that habitat reduce activity during the day or have some other physiological adaptations to deal with heat.
  12. External parasites are indeed one of the hypotheses. Another one is sexual selection. The others have been previously mentioned. By taking into account where our ancestors (australopiths) lived it was suggested that heat load reduction is more important when foraging in tropical habitats. There is also a suggestion that bipedalism evolved because of thermoregulatory benefits (https://doi.org/10.1016/j.jhevol.2016.02.006). These were more important to our ancestors as they moved from forest environments into more open habitats. Conversely it would mean that clothing likely only became more relevant when moving out of tropical climate zones. There are a range of suggestions on what behavioral adaptations might have occurred to protect from cold, but they appear to be fairly minor, especially concerning our physiological abilities to deal with heat. So far the strongest evidence we have point toward thermoregulation as one of the major influences.
  13. That is a good question and which is why it is necessary to gather information, such as - what is the timeline of hair loss? Was it rapid, or gradual? - how much fitness loss is associated with a given loss? - what kind of protection was feasible at any given point in human development (in terms of tool use and needs, hunting behaviour etc.) and how much of it could it offset the above fittness loss? - what are the benefits of mutations? If it requires so much effort to counteract its negative effects, why did it became dominant in the first place? Again, coming into a situation where certain traits are not needed does not make them magically disappear. As noted, the evidence so far to not seem to support the development of clothing before hair loss. I.e. hypotheses need to conform with existing knowledge. In that regard, persistence hunting was one of the hypotheses that tried to explain benefits of hair loss. I will also note that tentative evidence for man-made fires seem to predate tentative evidence for man-made clothing. Also, I note that the San people referenced earlier often wear very little clothing (up to somewhat recently) so it certainly does not seem to be that detrimental in climates where our ancestors lived.
  14. I think the issue is that it is very easy to make some sort of grand hypothesis in terms of evolution just by conjuring a scenario that somehow provides some kind of selective pressures that seemingly make sense. Things like the aquatic ape hypothesis are rightly criticized because of those. So if we think that we can come up with something better, at lease some level of evidence should be provided that whatever we come up with is in line with what we know (or at least have some sort of evidence). Fundamentally I find narratives that some species did this and this is why the lost a particular genetic trait problematic, as it conjures the idea that once a species did a thing, it resulted in genetic changes. The reality is the opposite of course. Mutations for hair loss occurred, likely somewhat frequently, but their frequency only increased when they either were not detrimental or became under positive selection. I was typing the comments below, when I noticed that joigus provided a similar reference so I am just keeping it brief and just state that the timeline when changes in hair patterns happened predated any evidence of potential tools that could be used for making some sort of warming clothes. So things like simple shelters or rain protection obviously had low impact on those mutations as all our relatives are still fairly hairy. But what the drivers are to keep hair loss around is still up to debate and as joigus pointed out, far from resolved.
  15. It is a bit funny to start with valid criticism, but then falling into the pit of, well, making things up. For example, if loss of hair was due to the wearing skin cloaks, then why did our presumably hairy ancestors start with that practice in the first place? How would they prepare skins to wear and is there any evidence to that end? I doubt that they would just wrap themselves in putrefying carcass (at least non of our cousins are doing it).
  16. I am not sure whether I understood the instructions, but I am licking coffee from the whiteboard now.
  17. You have to look out for migrating cells with flip charts. They are almost impossible to get rid of and cause inflammation responses everywhere.
  18. May I interest you in de-differentiation? A process where a differentiated cell decides to try something new and becomes a state that has higher flexibility and then changes again to a new job- but slightly different then those that differentiated directly into the role? I assume it is a process exclusively developed to annoy the heck out of cell biologists.
  19. It should also be noted that at least in US Colleges can only use factors such as race in admission only in a fairly limited sense. Specifically, they are only allowed to use it in order to create a diverse learning environment. While it can (and hopefully) does help underprivileged groups, I *think* they are not allowed to use that as justification. While only tangentially relevant, it should also be added that a minority of colleges use such mechanisms and it is banned in a few states for quite a while already. At the same time, if you ask folks some think that this is a dominant selection mechanism. I.e. similar to other efforts of equity, folks overestimate what is actual done (i.e. the level of course correction) relative to what is actually happening. And certain news outlets heavily use the assumed impact and treat it as reality to manufacture outrage. Edit: I should add that there is apparently a playbook/script of sorts by conservative groups that try to associate e.g. critical race theory and affirmative action with racism, gender identity to sexual exploitation/grooming and so on. While this was the purview of the extreme fringe, they have gotten sufficient traction that they have entered the mainstream (as evidenced by politicians espousing such rhetoric). So it is not just shitty reporting, as my post might have suggested.
  20. Well, authors are often very busy and most are unlikely to answer anything that can be (mis)construed as medical advice of any sorts. Complicated open ended questions are also less likely to be answered.
  21. In human fossils significant bran growth was seen around 2 million years ago. While cooking would be difficult to pinpoint as the relevant factor, a study in 2004 (Stedman, H., Kozyak, B., Nelson, A. et al. Myosin gene mutation correlates with anatomical changes in the human lineage. Nature 428, 415–418 (2004) https://doi.org/10.1038/nature0235) has found a mutation in a gene that leads to weaker jaw muscles, estimated to have occurred about 2.4 million years ago. In related primates, the jaw muscles are connected to large skull crests, which are absent from modern humans. Thus, the author speculate that when our jaw muscles stopped putting stress on the skull, the crests were not important anymore and might have opened the way to further skull growth. However, it has also been argued that some fossils still showed small brain sizes as recent as 1.8 million years ago (early Homo erectus). Now I don't know much about the consensus in terms of first fire use, but using wiki a range of 1.7 - 2 million years ago are mentioned. While the evidence from that time does not seem definite, it would line up with the fossil data for brain growth and myosin gene mutation. It does appear that fire use 1 million years ago is rather certain, so if we used this time point the largest discrepancy between fire use and brain growth would be around 1 million years ago (though certainly not millions). I have also read that folks speculate that beyond cooking meat, the simple act of pre-processing food (e.g. mashing and cutting) could have contributed to the lack of need of large jaw muscles and such tools were around since at least 2.6 million years.
  22. CharonY

    Political Humor

    Of course there are dozens of grifters waiting to take his spot, though.
  23. In addition, the gastrointestinal system for herbivores often is often complex and have sophisticated systems to extract nutrients efficiently (e.g. longer intestines, multiple stomachs), which require more space, too. Different belly size within a species are obviously caused by different reasons.
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