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Ken Fabian

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Everything posted by Ken Fabian

  1. Storm in teacup. People devoted to Feminist or Race Studies will tend to make every issue they explore about patriarchy and misogyny and racism. As Socialist idealogues make everything that is wrong about Capitalists and Capitalist ideologues make everying wrong about Socialists. A lot of the media can't help themselves; they trawl for people saying stupid or outrageous things that press people's buttons, in order to press people's buttons. Otherwise no-one would care what those people say, certainly not chemistry faculties. Encouraging participation in chemistry irrespective of gender or race or religion is mainstream reasonable and widely supported.
  2. Many inland peoples (eg African Bushmen, Australian desert Aborigines) who lived for many generations without any access to sea-foods have been healthy with fully working brains; the idea that early hominids couldn't develop large brains without an aquatic lifestyle sounds doubtful to me.
  3. I was referring to outgoing IR, ie from sun warmed ground radiating heat upwards. Optical depth in the IR band decreases with higher GHG concentrations, a bit like a fog getting thicker; more outgoing IR is captured at lower altitude with stronger down radiation. 50% upwards, 50% downwards is an alternative way to think of re-radiating equally in all directions; I've seen it described that way but it may be an approximation. For incoming solar IR high in the atmosphere - it isn't a large part of incoming solar radiation but it is there - about 50% re-radiates back to space and the rest adds it's energy to the atmosphere. Not sure if that is changed by having more CO2; it should be absorbed a bit higher up, yes, but not more - unless slower re-radiation (due to lower temperature) allows atmospheric circulation to carry a bit more of what energy is absorbed to lower altitude, before it re-radiates, ie retains a bit more in the atmosphere, ie a bit of warming. What happens at the bottom of the atmosphere is significant to surface temperatures but it is really just moving the same total amount of energy around - it isn't changing the amount of energy in the climate system. What happens at the top of the atmosphere is affecting the rate of outgoing IR reaching space and that is changing the overall balance between incoming and outgoing. That changes the total amount of energy. Top of atmosphere change is what makes heat accumulate.
  4. No, you need a lot better designed experiment than that and begin by showing that what happens with a glasshouse is the same thing (at smaller scale) as The Greenhouse Effect. It is not. What you will "prove" is that a glasshouse does not work like The Greenhouse Effect. Both get their heat primarily from visible light heating light absorbing materials - ground, water, plants etc including in the TGE case, absorption by clouds. A glasshouse works primarily by confining heat transfer by convection to a small volume, preventing loss of that heat to the greater atmosphere by that route. The Greenhouse Effect works by absorbing Infrared and re-radiating it. At the bottom of the atmosphere radiated heat is absorbed in the atmosphere above it, with about 1/2 of that radiating back downwards; more GreenHouse Gases means it is absorbed at lower altitude and down radiation is increased. At the top of the atmosphere the IR out to space is slowed by increased by more GHG's - it has to radiate from higher altitude to escape to space but the air is colder and it radiates less. A few metres of optical depth within a glasshouse is not equivalent to 20,000m in the atmosphere, even at 3,000 ppm of CO2. You would need concentrations in the hundreds of thousands of ppm to have equivalent IR absorption - and you still have to address the differences from convection. The question remains - why do you assume decades of top level science based studies and reports are wrong?
  5. Yes, it was the technology for successfully faking the Apollo moon landings that didn't exist 50 years ago. Not sure it exists now, but good enough for successfully faking a story about the moon landings being faked - good enough for the gullible, a low bar to step over - sure. @PeterBushMan - Was that the best you've got? I seriously doubt the production equipment used for making model T Fords exists anymore and lots of the documentation for that equipment is likely lost too but that doesn't mean model T Fords were fake. Anyone making a model T Ford now will use different methods.
  6. These kinds of options appear to offer ways to reduce the harms from the enhanced greenhouse effect but they don't address the emissions and the enhanced greenhouse effect that are the source of the problem, which are cumulative and get progressively more serious the longer emissions are not addressed. They also tend to not actually exist as actual, viable options. It is always worthwhile to explore all options, including the big geoengineering ones, but not as alternatives to addressing the emissions themselves using the capabilities that we have now and/or are within our grasp. Building clean energy that displaces fossil fuel use isn't hypothetical and at this moment in time isn't even a more expensive option. As I see it we should allow nothing to divert the primary focus of our efforts away from shifting our primary energy supply to non-emitting alternatives. In large part the current global growth of wind and solar, around and above 20% pa - I haven't checked but expect that solar alone is being added to the world's inventory faster than fossil fuel power plants were ever added. Largely the current growth is due to becoming cost competitive with fossil fuels without emissions considerations, but I believe a true zero emissions goal requires more foresight and commitment with greater growth of low emissions/no emissions alternatives than leaving it up to "free" markets that continue to give unfair advantage to fossil fuels, including by the enduring amnesty on climate accountability they enjoy. I don't think "free" ever truly meant free from accountability, nor that requiring it is anti-capitalist. The current market advantage of RE is far from absolute or happening everywhere and there are potential resource constraints and other bottlenecks - although I expect the worst of them will come from nationalistic geo-political gamesmanship, more akin to the denying supply that features with fossil fuels than any genuine resource shortages. It is still remarkable how well RE/EV's/batteries are doing, especially given that fossil fuels have powerful advantage from pre-existing incumbency - they are what energy companies and banks and energy planners know best and what cashed up fossil fuel companies lobby for relentlessly. And there is that enduring amnesty on any accountability for externalised climate harms, ie they continue to (mostly successfully) avoid accountability and they socialise those emerging costs to sustain exceptional corporate profitability, usually with systematic and successful tax avoidance thrown in. And if anyone can mass manufacture low cost, ultra safe, reliable, low cost modular nuclear that are low cost (did I mention low cost?) and conservative-right politics support for climate action comes out from behind their fossil fuel defending Wall of Denial we may see nuclear options become more widely used as well. But I don't expect much actual stratospheric aerosol injection, or Direct Air Capture or other CCS that isn't tied to efforts to extend the use of fossil fuels.
  7. I don't see how any solar IR absorption in the atmosphere could result in anything other than adding some energy into the atmosphere, ie add to warming. Affected incoming solar IR at the top of atmosphere should result in about 1/2 re-radiated back to space, from being absorbed from one direction and re-radiated equally in all directions, approximately half going up, half going down, with a net gain in energy in the atmosphere. IR from ground level mostly doesn't make it to space in one go. It has been a common misconception that CO2 should block incoming solar IR, as it blocks outgoing but that isn't the case; any energy absorbed within the atmosphere becomes energy inside the climate system. To "block" incoming IR takes reflection, not absorption.
  8. If it were absorption within the atmosphere that energy would be added to the atmosphere. It isn't absorption. This appears to be the correct option. As I understand it gaseous Sulphur Dioxide is the precursor to droplets of sulphuric acid that are reflective to sunlight. Being initially gaseous probably makes it easier to get pushed high in the atmosphere by volcanoes and for the resulting droplets to linger there, up to 2 years and global in effect. Human sources ie from fossil fuel burning rarely make it that high and have residence times of a few days and is more regional in effect. From NASA - This source doesn't specify the altitude of the clouds, but sounds like it has a reflective cooling effect. Regarding the initial question(s) - First, we don't know how to get volcanoes to erupt on demand or continuously. There are proposals for deliberately adding sulphate aerosols to the stratosphere but with (usually) aircraft, not via volcanoes. Sulphate aerosols aren't dust. Not sure dust is such a highly significant factor - probably doesn't linger long enough. But, to echo MigL, massively increasing volcanic activity seems counterproductive. The cooling effect of aerosols depends on the rate you keep adding, whereas global warming is dependent on the accumulated total of CO2 (over the timescales that matter). It doesn't fix the cause, just masks the effects - and the consequences are more complex than simply reducing global warming, ie may induce significant unwanted regional climate changes. My view is that - given existing climate politics - anything gives the illusion that we can keep burning fossil fuels at high rates and avoid the climate consequences is unhelpful - even where those attempts are sincere. Whether intended as an adjunct to commitments to building an abundance of clean energy and reducing emissions it will be used by opponents - and the apathetic - to reduce those ambitions.
  9. "Wheels" as a lasso style arrangement of tail or tentacle or flagellum type structures seems hypothetically possible to me - they wouldn't have axles or need them but could rely on twisting back and forth within each appendage itself to maintain near continuous motion. Near continuous because (off the top of my head) it seems to require a momentary "skip" on each turn, for the appendage to recover from the winding motion. No such structures have been observed to my knowledge. Wheels work best on smooth open ground with either low or no vegetation; only in a few habitats would wheels provide significant advantage.
  10. If we are chasing conspiracies, maybe it was developed in the USA on President Trump's order and deliberately released in Wuhan at the wet market near the lab ahead of the President's accusation/suggestion it came from the Wuhan lab. China would be hurt by the virus and by the accusation and America would be fine, having the world's best healthcare system and America will be great again... 😉 There is as much evidence for that theory as for Alfred's "must have come from the Wuhan Lab" theory - more "evidence", since we know Donald Trump could, unlike the scientists in Wuhan, be capable of that level of dangerous stupidity.
  11. Above - Should have been "achievable" not "achievement". I need to proofread before posting. I think over-population is a more intractable problem than decarbonising energy; I think we can educate and make contraception available and encourage but not regulate, not without costs that go beyond merely economic. Doing the best we can for the population we have and expect to have has to continue, even at risk of failure but the trade offs between the economic development that makes fertility a choice and resource constraints that make overpopulation a problem... is a problem.
  12. Availability of education, healthcare and contraception with a minimum of basic needs being met seems to be the most effective way to reduce population growth. Reducing population deliberately takes us into crimes against humanity territory - and almost inevitably means preferentially reducing numbers of people who aren't like us. Even schemes involving random selection are bound to include exceptions, for people like us. Problems like global warming being framed as overpopulation problems leads to presumptions of either solutions being unachievement (so don't bother) or else that anyone who is genuine must inevitably support policies that promote or lead to tyrannical control over people's lives (so must be opposed). Whereas I think it is more correctly framed as a dirty energy problem - so that when our primary energy is zero emissions even high populations with high energy use will have low emissions. It doesn't make solutions easy but it doesn't make them unachievable or tyrannical.
  13. A rise in the total atmospheric water vapor content due to warmer air holding more water vapour is being monitored and is occurring but relative to ocean volume it isn't nearly enough to counter the effects of warming on sea levels. A doubling of atmospheric vapor would be about 25mm of sea level, at current rates of change maybe 5 years worth, but that much increase hasn't happened and isn't expected. If anything increase in water vapor is happening slower than expected. But the most significant effect in climate change terms is the water vapor feedback, that effectively amplifies the warming from other causes - because water vapor is a greenhouse gas and warmer air takes up and holds more of it. A bit of warming increases water vapor content and that causes more warming.
  14. Other apes have fur from birth until sexual maturity; having fur during the juvenile stage isn't a secondary sexual characteristic but would be a normal juvenile trait. Not having it is the peculiarity. The furlessness doesn't go away with puberty. But it could be a delay or missing out of an earlier growth stage than that. When puberty starts does appear to vary between populations - the duration of the furless childhood stage might change but otherwise it looks like the same pattern of long hair on head and only fine vellus hairs elsewhere is universal. And yes, Heterochrony, including Neotony - changes to timing, rate and duration of growth - has been suggested as involved in furlessness and I'm inclined to agree, but it looks more complicated than just that. The gain in follicular nerve supply doesn't appear to be a consequence of a change in timing. Going by Montagna it sounds like it is an exceptional change, but I'm not sure anyone knows; I'm not sure we'll see the kinds of comparative anatomy that Montagna did, that included examination of human and animal skin samples, repeated or extended. Maybe genetics will end up telling us to what extent the factors that affect the size of the hair shafts affected the nerve supply - and what was the result of other evolutionary changes.
  15. It would be very odd for a trait that appears to offer no special advantage and considerable disadvantage except in exceptional circumstances would be selected for repeatedly in widely different environments and result in all populations evolving the exact same trait, all very recently, all since speciation. I would expect it to be expressed with significant variation in separate human population if that were so but it isn't; it seems to be a trait that has effectively been unvarying - irrespective of how varied adult hairiness is (a secondary sexual characteristic) childhood furlessness is universal. A trait shared universally by all members of a species will almost certainly go back to common ancestors. I think we really do have greater sensitivity than related apes - and by implication, than our shared ancestors. I can't prove that of course. Doing experiments with chimps and bonobos to compare to humans to determine relative sensitivity seems difficult but doable - they are our best stand-in for our common ancestors but that can't deliver certainty. The late Mr Montagna seems to have thought the sensory sensitivity of human skin via hairs/hair follicles was exceptional. My own experience is of high sensitivity - but that is subjective. That so many people fail to notice the difference between the sensations from hairs and sensations from direct skin contact and appear to believe they add nothing at all is maybe a question for Psychology. Arriving at any definitive conclusions is probably expecting too much - I don't claim to have any, barring being confident that we can rule out sexual selection because... the furless child. I have some hopes that delving into DNA might shed light on it.
  16. Their children were presumably furless when humans left Eastern Africa. (I prefer that to hairless, because hairs are still there, just smaller... and with better nerve supply). That every human child is furless in modern humans means it is a homologous trait that goes back to (at the least) the emergence of homo sapiens as a species. Montagna, approaching it from comparative anatomy asked - Furlessness - the furless child - was part of homo sapiens first. Variations like that greater adult hairiness came later. If it is beneficial to adults it will be beneficial to children. Furred animals pretty much all have furred young. Smaller body size usually means greater heat loss and susceptibility to cold and human babies are especially vulnerable. Also more susceptibility to overheating - which would be more pronounced without the furlessness in combination with greater ability to sweat for cooling. Do children make more internal body heat than adults? They are often very active. Mistermack mentioned lion cubs dying from cold during wet weather - but having fur that is soaked and stays wet may be a greater risk for hypothermia than having no fur. Similar to wet clothing raising hypothermia risk. I think it's a case of sometimes it will be a benefit and sometimes it won't. Humans - and our hominid ancestors - were better capable of finding fixes and workarounds than any other species.
  17. @mistermack - I am not disagreeing that fire and shelter and maybe clothing too would have been important to the success of early furless hominids, and ever since. It could be a significant reason the furless trait could be sustained rather than taken back out of the gene pool even if, for a time, for some reason or reasons, it was a common variant. The timing isn't entirely clear but fire use goes back at least that far. Evidence of early shelter making is harder to establish, but very possible, even very likely they were used very early on. A maybe on clothing because shelter and fire would probably be sufficient in a warm climate - as is the case with modern humans, including well outside the warm tropics going by Australian Aborigines, who often wore little more than versions of loincloths, with kids going naked most of the time. Animal skin cloaks and wraps were used in colder places in cold conditions. Oiling the skin of children in Winter was apparently practiced in some colder regions too - I surmise for being water repellent to reduce cold from prolonged time being wet. It is the use of these as the primary cause for evolving furlessness that I disagree with. But not vehemently; I expect multiple factors at play, not all at the same time. I think there are some sub-questions that might be answered - was it a progressive loss of fur over many generations? Or was it a distinct furless variant - furless individuals born to furred parents via specific mutation - that swept through the population because it gave survival advantage? Was it sexual selection for attractiveness or natural selection for survivability? Or a dominant genetic mutation that gave no advantage but was survivable, that induced clever tool making problem solvers to rely on and develop better shelter and clothing, that gave a thermo-regulatory advantage far beyond what any fur, even seasonally shedding, can deliver? And there is still the gain in sensory sensitivity of hairs in humans to explain, that has nothing to do with thermo-regulation. I had thought maybe the sensitivity gain was "spandrel" - the hair shaft size shrank but the follicular nerve supply of much larger hairs remained. Except that Montagna's comparative anatomy makes clear there is a significant increase over what the (larger) hair follicles of related apes have. It may be invisible but that looks as profound a difference between us and our primate relatives as being visibly furless is. I think not progressive fur loss - because... the furless child. There is no - or very little - variability of furlessness in childhood and if it were a trait subject to incremental change it ought to show variation. Not sexual selection because... the furless child; furlessness has to already be in place in children for preferentially choosing youthful, pre-pubescent furlessness in a sexual partner.
  18. @mistermackDepends on the climate, surely. Keeping active by day, huddling together by night would do in milder climates. Hominids have been clever tool users and problem solvers for a very long time - even dragging vegetation over themselves can provide insulation. But, yes, clothing and shelter and fire may well have preceded furlessness and made it easier to cope with when it happened and perhaps those were used or known but not used all the time; furlessness could make their use more of a necessity. But I don't see how they would lead to the evolution of the furless child; where is the selective advantage? I think just not needing fur to keep warm when fur does provide significant benefits - even if not all the time - isn't going to be enough for a species to lose it. As an aside I've heard it said that hiking in cold, wet conditions without clothes is less likely to result in hypothermia than wearing wet clothes; my own experience hiking in swimming shorts in the rain seems to support that - like swimming, as long as I kept moving I wasn't cold - but I haven't done that outside a mild climate or in extreme conditions.
  19. It seems more likely to me that use of clothing was a response to being furless rather than inducing furlessness - a parental response to their furless children suffering from cold perhaps. It is certainly possible the use of clothing and shelter and fire came before the loss of fur and gain in sensory sensitivity but I don't see how it would lead to evolving furless children. I have dogs that are very pleased to wear warm jackets in winter but I don't expect dogs to evolve furlessness as a consequence. There has been more going on than reduced hair size. Skin has gotten tougher and makes more perspiration and gained (variably) resistance to UV. Hairs gained sensory sensitivity. Seems unlikely they happened simultaneously or for the same reason. Abebe Bikila famously won back to back Olympic Marathons with bare feet. I don't see any fundamental problem with running long distances without shoes. Australian desert Aboriginals traveled long distances in harsh conditions without footwear but I'm not aware of persistence hunting as a usual hunting method. Sneaking up on prey and using spears or hunting boomarangs seems more usual. Chasing down wounded prey no doubt happened - but I expect marksmanship would be criticised; a few times and young hunters would learn the worth of taking prey down quickly, to avoid all that chasing after them. African Bushmen however, are noted for long distance running and persistence hunting - the Kalihari Desert is a unique and challenging environment. More usually a variety of hunting methods were used, from snares and traps to ambushes at water holes or river crossings (which the Kalihari doesn't have). But I also have some reservations about reliance on persistence hunting of large prey as the primary source of high protein food, but conceivably at some extreme bottleneck - where the very survival of the species was in doubt such as due to extreme anf persistent drought - it may have been so... if an ability to sweat profusely had already developed and overlapped with individuals having loss of fur. There are some furry primates that sweat a lot.
  20. Only the adults have more (as in larger) body hairs. The children are as furless as children everywhere else. I think that is a significant observation that has been largely overlooked in developing plausible explanations for how we got to be a furless ape. It tells us that greater adult hairiness within some groups must have evolved later than the childhood furlessness that is universal across our species. All the variations of hairiness in adults, barring perhaps some dimorphic (male vs female) differences, would have arisen after speciation. If I could write academic style papers I would address this, along with the sensory function of hairs - "hairlessness" itself is in my view better framed conceptually as a developmental trait and might be better described as a furless childhood condition than as a species with furless adults. Which means any hypothesis for childhood furlessness based on sexual selection has serious problems; how does choosing a less hairy adult mate lead to children having no fur? The childhood furlessness has to pre-exist for sexual selection to be able choose less hairiness in adult mates.
  21. Yes, I am inclined to think that there were times and circumstances where being able to keep going in hot conditions would be significant and other times and circumstances where having reduced exposure to parasites would be significant. I don't think it will be down to any one thing except perhaps the presence of a furless mutant variant at the right time. But then it could be the other way around - that body hairs staying small was driven by parasite - and parasite borne disease - avoidance and the increase in sweat glands came later and turned it into a significant heat dissipation advantage. Susceptibility to extant parasite borne disease and the presence of mutations that reduces it would have a very strong selective effect, even within a single generation; the furless mutant types, despite the problems - with the problem solving, tool using capacity to work around the problems
  22. And I'm intrigued by the evolution of a significant gain in sensory sensitivity in humans via those changes to patterns of hair growth. Enough to wish I could write something publishworthy about it. Having small hairs means it takes less to disturb them. Being effectively sparse - hairs not laid against each other - means there is less dampening of their movement should something deflect or vibrate the hair shafts. That was my initial thinking for why my body hairs seemed so especially sensitive - able to feel the air vibrations off a fly that does a close pass, without any physical contact. Or to notice an Australian Paralysis Tick bumping hairs on it's way up my leg, enough look and pick it off before it dug in. Anyone who said body hairs serve no useful purpose hasn't avoided the painfully itchy bites of an Australian Paralysis Tick. Clearly not 100% effective, but there's that ability to get so deep in concentrated thought as to ignore our senses; maybe our ancient ancestors paid more attention. On the other hand having very sensitive hairs make busy, buzzy flies almost unbearable; they prompt humans to take significant actions, besides swipe and swat and swear. Anything that can provoke children to screams of "get it off me, get it off me!" is not a functionless leftover. As an aside - or even more aside - I even wonder if the most common sensations hairs make being irritation is a subconscious part of the appeal of body hair removal. It was a few years before I encountered William Montagna's "Evolution of Human Skin" and learned that human hair follicles, no matter where or how small, are especially rich with nerves in comparison to the hairs of other extant apes - more like the vibrissa, the dedicated feeler hairs than their ordinary hairs - If nothing else, this seems relevant to any ecto-parasite hypothesis for how we got the particular patterns of hair growth that humans do.
  23. @mistermack - Fire was also used to drive prey animals towards hunters and burning of dry grass and vegetation around camps was done to make them safe from wildfires. That kind of burning also results in fresh green plant growth as the area recovers and that attracts grazing (prey) animals.
  24. An ongoing interest of mine has been what is usually (misleadingly) named human hairlessness - notably smaller hairs that leave human skin exposed and visible over most of the body, which is so different to related apes and primates. But it also comes with a greatly increased follicular nerve supply ie increased sensory sensitivity of those hairs. That is not a visible trait but is something subjectively experienced, presumably by every human barring those that for some reason have no body hairs, or they don't have nerve connections. How furlessness (I prefer that term) evolved has been an ongoing puzzle that has engaged the minds of many serious contributors to science but the greater puzzle to my mind has been how so many people attempting to explain it could entirely overlook that sensory function - many to the point of claiming our fine body hairs serve no useful function at all, despite living immersed in the sensations they provide. Busy, buzzy insects, puffs of breeze, slide of cloth as we move, close passes by hard objects - sensory awareness of them is a useful function. I have a picture in my mind of Charles Darwin in short sleeves, deep in thought and unthinkingly swiping at annoying flies tickling the hairs on his arms as he composes the line "No one supposes that the nakedness of the skin is any direct advantage to man: his body, therefore, cannot have been divested of hair through natural selection." Which I think is both false - he admits as much in his response to a naturalist named Belt who did suppose that by suggesting ease of finding and removing skin parasites as an advantage - and an example of "not even wrong" type of wrong; it casts the question as one of the advantages of absence of hairs, when hairs are not absent, but are small with high sensory sensitivity. That capacity for such deep thought and concentration that we can lose awareness of our senses has to be unusual in the animal kingdom - I do that too - but that so many people who were seriously attempting to understand how human furlessness evolved could have such a big blind spot is intriguing.
  25. The false perception that we are perceiving and thinking and acting in the present when there is actually a significant time lag has intrigued me - a little bit, or maybe a lot of predictive power needs to be involved in doing that.
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