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August 24

Another question about ice halos

Is there any specific resource I can visit to learn more about ice halos, how they form, all the different types, and find pictures of them all? The sole picture of a subparhelic circle at Subparhelic circle is not very good, and is also the sole picture I’ve been able to find on Wikipedia containing diffuse arcs, a type of halo the article for which is a red link.

I feel like Wikipedia/Wikimedia Commons are not sufficient resources to pursue the level of knowledge about halos I’ve been interested in obtaining ever since one random fall down a Wiki-rabbit hole. Any good suggestions? (Kind of like Wikipedia, but about ice halos, if that exists?) Thanks! Cheers, 𝔰𝔥𝔞𝔡𝔢𝔰𝔱𝔞𝔯 ^{(𝔱𝔞𝔩𝔨)} (any/all) In solidarity. 08:42, 24 August 2026 (UTC)

This site is fairly comprehensive. {The poster formerly known as 87.81.230.195} ~2026-43920-01 (talk) 13:33, 24 August 2026 (UTC)

Thanks; that’s just the kind of thing I was looking for! Cheers, 𝔰𝔥𝔞𝔡𝔢𝔰𝔱𝔞𝔯 ^{(𝔱𝔞𝔩𝔨)} (any/all) In solidarity. 22:16, 25 August 2026 (UTC)

August 27

Charles Darwin

One argument against evolution is that Charles Darwin renounced evolution on his deathbed. Is that true? Loksha (talk) 04:38, 27 August 2026 (UTC)

The evolution theory as Darwin described it has long been outdated, and whether a model is useful or not does not depend on the opinions of its inventor.

e.g., if Einstein renounced relativity on his deathbed, general relativity will still be a highly useful model to describe the observable universe. 海盐沙冰 _{/ aka irisChronomia / Talk / Uploads} 05:41, 27 August 2026 (UTC)

Rather than painting Darwin's description as being "outdated", I'd say that the scientific theory developed by Darwin has been enriched in the so-called "Modern synthesis" by adding more elements, such as Mendelian inheritance, itself enriched by the discovery of the molecular biology of DNA as being the repository of genetic information. The core element of the theory of evolution, also as it is understood today, was, is and remains the theory of natural selection, independently conceived by Darwin and Alfred Russel Wallace, but largely popularized by Darwin (see also Development of Darwin's theory).  ​‑‑Lambiam 08:39, 27 August 2026 (UTC)

And in any case it's not true. {The poster formerly known as 87.81.230.195} ~2026-43920-01 (talk) 06:26, 27 August 2026 (UTC)

That sounds like something put about by mischievous fundamentalists, but Jesus also had his doubts in the end. Shantavira|^{feed me} 07:10, 27 August 2026 (UTC)

Evolution is a demonstrable fact. ←Baseball Bugs ^{What's up, Doc?} carrots→ 07:48, 27 August 2026 (UTC)

And the renunciation appears untrue, as examined in this reference supplied by antievolutionists: Morris, John D. "Did Darwin Renounce Evolution on His Deathbed?". www.icr.org. Graeme Bartlett (talk) 08:34, 27 August 2026 (UTC)

No, he did not; at the very most, he may have somewhat "given up" on championing Natural Selection by the time he died. Evolution gained near-universal acceptance by natural scientists very quickly after Darwin's and Wallace's papers on evolution by natural selection were published and Darwin's book the following year. Natural Selection as the mechanism had very little support at that time. The favoured mechanism was what is now (somewhat misleadingly) called "Lamarckian evolutionary theory" - heritable acquired characteristics (now almost entirely rejected - but see epigenetics).

Darwin himself never completely ruled out acquired characteristics as a contributing mechanism. Wallace categorically rejected it.

Neither Darwin nor Wallace particularly thought that the degree to which the human brain had evolved could be explained by natural selection. Darwin put forward that humans' heavy use of their brains caused them to get bigger over generations. Wallace proposed a supernatural cause. Darwin thought that Wallace making such a suggestion would be the final nail in the coffin of their theory.

Their theory gained acceptance some decades after Darwin's death, after the discovery of Mendelian genetics. ~2026-46623-92 (talk) 07:10, 28 August 2026 (UTC)

Since no-one has linked the actual article - the evangelist who claimed to have visited Darwin on his death bed and heard his recantation was Elizabeth, Lady Hope, and there's lots of information about it there. Darwin's family have said she never actually visited him, there's no evidence that she did, and even other evangelists have publicly called her a liar. Smurrayinchester 07:33, 28 August 2026 (UTC)

It should also be noted that the validity of a scientific theory isn't determined by 'renouncements', any more than it is by endorsements. If Darwin had renounced it (which he didn't) it might have led people to look at the evidence again, but it wouldn't have affected the evidence. Which is utterly overwhelming... AndyTheGrump (talk) 14:15, 28 August 2026 (UTC)

FYI, OP has been blocked.

However, I like the discussion anyways. 海盐沙冰 _{/ aka irisChronomia / Talk / Uploads} 14:18, 28 August 2026 (UTC)

It's not true that Darwin renounced evolution on his deathbed; and it's also not true that, even if he had done so, that would be an "argument against evolution." Take your pick. in solidarity Chuntuk (talk) 14:31, 2 September 2026 (UTC)

August 28

How many dinosaur species survived the asteroid, esp. until today?

As we all know, the Cretaceous–Paleogene extinction event wiped out the dinosaurs - except some lines, at least parts of which evolved into modern birds. This raises two somewhat obvious questions:

1. How many species of dinosaur alive at the time of the impact did survive? The number depends on answering when the last common ancestors of the subgroup of birds lived. This must be done over the molecular clock in their genomes, but in many cases is hard to decide whether this last ancestor lived before of after the impact. Still, I assume that there are estimations?
2. How many dinosaur species do we know of that survived the impact and for sure did not evolve into modern bird species? What was the most distant relative of birds of them?

--KnightMove (talk) 08:42, 28 August 2026 (UTC)

Some Dinosaurs Survived the Asteroid Impact describes the work of Jim Fassett of the U. S. Geological Survey, who has contraversially identified some bones of a hadrosaur as post-dating the extinction event, but the jury seems to be still deliberating. Alansplodge (talk) 13:56, 28 August 2026 (UTC)

1) Birds were already a distinct group within dinosaurs before the extinction event. It's not that surviving dinosaurs evolved into birds, its that birds were the dinosaurs that are known to have survived. 2) whether any non-bird dinosaurs survived the extinction event is unclear for several reasons. Do you mean the actual impact and the immediate days after? Or could the "extinction event" be a change in the environment that lasted a few tens of thousands of years? This would be a long time by human standards, but almost instantaneous by geologic standards. Aside from that, not all species alive at any one time will actually show up in the fossil record. This famously leads to "Lazarus taxa" like the coelocanth that are found alive even though they had disappeared from the fossil record tens of millions of years ago. Finally, bones found in rocks younger than the extinction event have to be shown to most likely not be secondary burials out of previously eroded materials. --User:Khajidha (talk) (contributions) 19:45, 28 August 2026 (UTC)

1. I'm fairly certain that the last common ancestor of all birds was quite a long time before the K/T extinction event..for instance, owls already supposedly existed as a distinct group before that event took place, and owls are in the Neoaves group, while other groups, the fowls and the Palaeognaths, branched off before the last common ancestor of all Neoaves. So I would guess the last common ancestor was likely at least 100 million years ago. Molecular dating isn't very reliable for giving precise absolute dates; it is more useful for telling which groups diverged before which other groups, but the exact when lacks in precision. As for the number of species that existed 66 million years ago and werent made extinct by that event, that is not a question that it is possible for anyoneto ever find out the answer.

2. None. All remaining dinosaurs except birds went extinct at that time. Along with many other groups of animals. And all tetrapods larger than 50 lbs that existed at that time, with the sole exception of sea turtles, went extinct at that time. ~2026-46623-92 (talk) 20:12, 28 August 2026 (UTC)

Question 2 does allow for clades of birds that survived the impact, but died out later. That could include a clade that branched off 67 million years ago, produced a dozen species and went extinct 63 million years ago. I don't know whether science knows any of those. PiusImpavidus (talk) 11:13, 29 August 2026 (UTC)

Exactly. Only the tiniest fraction of organisms fossilize. Even from the most fossil-rich periods, we have fossils of only a tiny fraction of taxa -- the ones that happened to live in locations with conditions (or subject to disasters) that favor fossilization.

It's quite conceivable that small populations of many types of dinosaurs straggled on for years, decades, millennia, even some millions of years after the impact -- but fizzled out due to harsh conditions or too-small and isolated populations subject to the negative effects of genetic bottlenecking. But we haven't found their fossils yet. -- Avocado (talk) 14:44, 29 August 2026 (UTC)

Not a single fossil of a non-avian dinosaur has ever been found above the KT boundary. Cretaceous–Paleogene extinction event#Birds states that at least the duck (Anseriformes ), chicken (Galliformes), and ratite lineages predate the KT event. It is suspected that the Telluraves also arose shortly before the event. Abductive (reasoning) 10:23, 30 August 2026 (UTC)

Fwiw, I'm not suggesting birds evolved only after the impact. I'm suggesting that if one in a million (it's probably even less than that) vertebrates who die end up fossilized, it's quite likely that there are entire genera from both before and after the impact that we have absolutely zero record of. That we have no record of them doesn't mean they didn't exist.

This source suggests it's one bone in a billion, so that's more on the order of 1 in 10 million individuals even if each bone is from a different individual. And of course, the sampling is not random -- context heavily biases the sample. (The article indicates fossils survive of only 0.1% of all species to have lived, though one has to assume vertebrates are represented at a much higher rate than purely soft-bodied organisms.)

It seems reasonable to assume that there were at least some habitats that did not favor fossilization or discovery of fossils, and that did favor or permit survival -- at least for a while -- of some small number of dinosaur species. Just because we haven't found the fossils doesn't mean they don't exist, and just because fossils don't exist doesn't mean the critters didn't. -- Avocado (talk) 14:25, 30 August 2026 (UTC)

But here's the thing: they were all annihilated within hours. There were no warm-blooded animals over 25 kg left. Abductive (reasoning) 00:48, 31 August 2026 (UTC)

Citation needed. The section Cretaceous–Paleogene extinction event § Duration has this to say:

"The extinction's rapidity is a controversial issue because some researchers think the extinction was the result of a sudden event, while others argue that it took place over a long period. The exact length of time is difficult to determine because of the Signor–Lipps effect, where the fossil record is so incomplete that most extinct species probably died out long after the most recent fossil that has been found.^[189] Scientists have also found very few continuous beds of fossil-bearing rock that cover a time range from several million years before the K–Pg extinction to several million years after it.^[34]"

 ​‑‑Lambiam 07:08, 31 August 2026 (UTC)

No amount of typed words here will change the fact that they all died, and not one dinosaur was born, after the meteor hit. The 1982 article you think means something is an artifact of hidebound thinking, as stated in Chicxulub crater article: "The Alvarezes' impact hypothesis was rejected by many paleontologists, who believed that the lack of fossils found close to the K–Pg boundary—the "three-meter problem"—suggested a more gradual die-off of fossil species" Abductive (reasoning) 09:08, 31 August 2026 (UTC)

How do you know this for a fact? I don't see why this would be so. In fact, it seems extremely unlikely to me that it is true. Some groups of non-avian dinosaurs (for example the mosasaurs) almost certainly went extinct because of the collapse of the food chain, which would hve been far more gradual. We know some mammals and avian dinosaurs survived. What is so different about non-avian dinosaurs that would have caused their collective instant death?  ​‑‑Lambiam 21:06, 31 August 2026 (UTC)

Agreed. Our bias towards thinking of dinosaurs being 'large' is skewed by the fact that smaller animals fossilise less often (because they are more apt to be eaten whole or consumed by scavengers after death) and less well. The avian dinosaur (bird) lineages that survived were likely smaller than some that didn't, but there were likely equally small non-avian lineages too.

Perhaps surviving small mammals' homeothermy proved too great an advantage, and they quickly ate all the small dinosaurs that couldn't fly during cold snaps in the unstable weather following the impact – although like the birds, any small non-avian dinosaurs might have already been homeotherms too.

A recent analysis has proposed that the immediate after-effects of the impact caused the entire upper atmosphere to glow red hot for several hours, effectively roasting any creatures on the surface: only those who chanced to be in burrows, caves or similar shelters could have survived. Thus survival would have depended on individual species' habits, and/or chance. {The poster formerly known as 87.81.230.195} ~2026-43920-01 (talk) 04:49, 1 September 2026 (UTC)

The bias is pure wishful thinking by humans who liked dinosaurs as kids. They all died. Not one fossil has been found above the boundary. The devastation was beyond most peoples' imagining. Abductive (reasoning) 11:59, 1 September 2026 (UTC)

And no coelocanth fossils appear in a many millions of year stretch of deposits. You are making too broad of an assumption. What you say here sounds a lot like the hyperbolic statements you would hear on a cable television special on dinosaurs. --User:Khajidha (talk) (contributions) 17:54, 3 September 2026 (UTC)

The problem with homeothermy being the reason (or the main reason) is that animals we would call "dinosaur" rather than "bird" if they lived today, such as Velociraptor were at least somewhat warm-blooded. The differences between, say, Dromaeosaurids and early birds was pretty thin: both had feathers, both were warm-blooded, etc. Matt Deres (talk) 15:27, 1 September 2026 (UTC)

August 30

wedding rings and trust

i saw a post on Facebook that said people trust others more who wear wedding rings but i can't determine anything from Google on this besides women "do not find men signaling engagement, or being perceived as having a partner, more attractive or higher in socioeconomic status. Furthermore, signs of engagement did not influence the women's reported willingness to engage in short-term or long-term relationships with the men." . Our article on wedding ring is missing perceptions of wedding rings which could be a section. any help? 781h (talk) 21:43, 30 August 2026 (UTC)

I did not readily find any mention of a scholarly study confirming this. Of course, there are countless reports of sociological studies trumpeting this or that result based on a shoddy set-up and dubious use of statistics that cannot be replicated, so we cannot eliminate the possibility that the post was based on an actual study. But, at least as likely, the author of the study just happened to believe this but presented it as an established fact, rather than their belief. In any case, the statement would require cultural context.  ​‑‑Lambiam 06:58, 31 August 2026 (UTC)

@781h I regret to inform you that Facebook is full of cr*p. Shantavira|^{feed me} 07:53, 31 August 2026 (UTC)

A peer-reviewed study in a reliable published source that reports objectively about "Perceptions of wedding rings" could justify a new section on this subject. Without such a source, WP:NOS forbids the original work of synthesizing such a section. ~2026-39925-22 (talk) 11:14, 31 August 2026 (UTC)

The OP's question does contain statements of perceptions that can be backed up by peer-reviewed studies, but it appears that the particular perception of trust the OP asked about cannot be backed up that way.  ​‑‑Lambiam 20:46, 31 August 2026 (UTC)

August 31

Bypass PCV in Mazda Skyactiv engine

The PCV in the Mazda Skyactiv engine puts a lot of gunk in the air intake that goes straight into the throttle body valve, which causes extreme soot buildup on the inside of the valve. Knowing this, I remove the throttle body and clean the inside of the valve when I change the oil. It made me wonder if there was something else I could do - which takes this into Science territory... Is there a filter I can use to remove combustible particles from the air intake? A standard air filter won't do it (so there no point in moving the PCV to the other side of the air filter). Is there a material that attracts little carbon and oil particles that I can run the PCV through? I'm thinking an S turn to get as much collected before going into the main air intake and then I can just pop that off and clean it out periodically. In older engines with port injection, this wasn't a big deal because gasoline vapors swirled inside the throttle body and kept it mostly clean. The Skyactiv is direct injection, so there's pretty much no gasoline vapors running around. So... perhaps a solution is to artificially introduce gasoline vapors into the air intake. ~2026-46630-01 (talk) 12:51, 31 August 2026 (UTC)

I verified that if I move the hose to the other side of the air filter, I get an error code from the monitor (similar to simply removing the hose). So, I'm looking at making the hose so it tries to collect fumes before they enter the air intake. I'm still thinking that I will need an S-bend with a material that readily collects gas and oil fumes. ~2026-46630-01 (talk) 13:28, 1 September 2026 (UTC)

Dumping all the PCV fluids into the air filter is not good, don't do that. It seems a bit odd to mess with a Mazda engine. Having said that some variants get an air/oil separator in the PCV line. Does yours? Greglocock (talk) 07:00, 2 September 2026 (UTC)

The Mazda engine (skyactive) has a PCV hose connected to the air intake between the air filter and the throttle body. I didn't do it. It came that way. When I discovered that it cakes soot on the inside of the butterfly (a pain to clean), I disconnected the hose and the engine threw many error codes. I put it back and it ran fine. So, I'm trying to find a way to remove pollutants from the air going into the throttle body before they turn into black soot. ~2026-46630-01 (talk) 14:18, 2 September 2026 (UTC)

This website says that this problem can be caused by a faulty PCV valve, or by using cheaper low-quality engine oils rather than synthetic. MinorProphet (talk) 01:02, 3 September 2026 (UTC)

September 1

Chemical smell on new clothes

I’m trying to find out what is causing a chemical smell that I’ve been noticing in many new products over the past several years, particularly clothing and bedding. The smell does not go away even after washing it a couple times.

One thing that makes me especially curious is that products from completely different brands seem to have a very similar smell. It isn’t just one particular type of clothing or one manufacturer. I can buy different clothes from different places and they can have what seems to be the same chemical odor.

I have also spoken with other people who have noticed this. For example, someone I know who works at a large department store that sells clothing and many other types of merchandise has noticed the same change and agrees that products did not used to smell this way.

In the last couple months I have started noticing what seems to be the same type of chemical smell on other products as well, including paper products such as napkins and paper towels, and even the plastic housing of an inhaler I received. I cannot use these products because the odor triggers my asthma.

Some people have suggested that the smell might be formaldehyde. I’m not convinced that is the explanation. I have encountered what I believe was the smell of formaldehyde at a funeral facility, and the smell seemed quite different from the odor I am finding on these newer products. I also understand that formaldehyde or formaldehyde-based treatments have been used in textiles in the past, yet I do not remember older clothing having this kind of strong, persistent smell.

So what I would really like to understand is what has changed.

Is there a particular chemical or group of chemicals that is now being used much more widely in clothing, bedding, paper products, plastics, or other consumer products and could explain this similar odor? Is it actually a new chemical, or could it be an older chemical being used in a different way or in a higher concentration?

I’m also wondering whether this could have something to do with changes in manufacturing and quality control since the COVID lockdowns. Could a problem with the manufacturing process, such as using too much of a chemical, an incorrect mixture or formulation, or inadequate processing or curing, produce a much stronger odor than the same type of treatment used in the past?

I would like to know what the chemical is. I’m trying to find out whether anyone with knowledge of textile chemistry, chemical manufacturing, or industrial processes can identify what might be responsible and explain why this seems to have become so much more common in recent years. Kitchensink1 (talk) 06:35, 1 September 2026 (UTC)

All smells are due to chemical compounds. Are there any familiar smells of known substances that you can compare this one to?  ​‑‑Lambiam 09:46, 1 September 2026 (UTC)

Pesticides maybe? To prevent the spread of invasive species, shipping containers are routinely treated with pesticides, which may leave a smell on the goods inside. If the pest control department of the port of Shanghai changes procedures, the whole world can smell it.

Hanging your textiles on a line in sun and wind for a couple of hours (like many people do to dry their clothes after washing) may be more effective than washing. PiusImpavidus (talk) 09:47, 1 September 2026 (UTC)

Much of the smells found in sealed plastic items comes from the speed of the assembly line. In the past, items were produced. They aired out to release the gasses absorbed during manufacture. Then, they were sealed in plastic that has also set out to release gasses. But, everything is faster now. The manufactured items go straight into packaging and the packaging goes straight from production to use. It isn't that some chemical is being added. It is that the chemicals we used to not notice because they were released before packaging are now trapped inside the packaging. ~2026-46630-01 (talk) 11:20, 1 September 2026 (UTC)

September 2

Plant crossing

I'm bad at botany, and trying to link the word "plant hybrid" / "crossing" (to describe hybrid grape in Concord grape) is giving me headaches.
From what I can find, all of the following seem to be a viable link target:

• Propagation of grapevines#Terminology
• Hybrid (biology)#Animal and plant breeding
• Plant breeding <-- Can't find an immediately relevant section

海盐沙冰 _{/ aka irisChronomia / Talk / Uploads} 07:01, 2 September 2026 (UTC)

Not a botanist either, but IMO it depends on whether you're linking "hybrid" or "hybrid grape" (second for the first, first for the second, never the third). Clarityfiend (talk) 13:13, 2 September 2026 (UTC)

September 3

Questions for older people: on the 1970s and 1990s: color vision.

In 1942, a Dr. Walls came out with a book that said cats and dogs are both colorblind. It wasn't until 1989 that some professors published a paper that dogs can, indeed, see some color, mostly blue, yellow, and brown. However, a lot of people don't actually know this, a lot of people that I've asked, still believe dogs are completely colorblind. But it isn't like that for cats, a lot of people know cats can see some color. I asked ChatGPT, when was it discovered that cats can see some color, and the answer is 1970.

N. W. Daw & A. L. Pearlman (1970), “Cat colour vision: evidence for more than one cone process,” Journal of Physiology 211:125–137.

Regarding 1989 dog article, that article must have been low key. Meaning, it wasn't advertised on TV, so it was only known to the particular scientific community, such as optometrists and such. My guess was, it wasn't like this with cats, and 1970. Does anyone think that when cats were discovered to see color, this new discovery was broadcasted all over on TV, and talked about, so the generations after were taught cats can see color, but it didn't happen with dogs? ~2026-47920-23 (talk) 01:38, 3 September 2026 (UTC).

I'm also wondering about children's books. Does anyone know of any children's books that said things like "dogs cannot see color, but cats can?" ~2026-47920-23 (talk) 01:40, 3 September 2026 (UTC).

I wouldn't be surprised if many adults still think that bulls can see red. ←Baseball Bugs ^{What's up, Doc?} carrots→ 01:56, 3 September 2026 (UTC)

Here are links to recently published texts, written for children, that state this:

• Dogs cannot see color. They are color-blind.
• Cats (and dogs) cannot see color.

 ​‑‑Lambiam 07:25, 3 September 2026 (UTC)

I found on my shelf a children's book published in 1984, stating (amongst other things) that

• the primary colours for bees are ultraviolet, yellow and blue;
• bulls are assumed to be colourblind and don't attack the cloth because it's red, but because it moves;
• many animals, like cats, dogs and horses, are assumed to be colourblind and see the world in shades of grey and pale shades of colour;
• fish, reptiles and birds that are active during the day can see colours.

I note that the book doesn't give a precise definition of seeing colours. In particular, it doesn't discuss dichromats.

As I understand it (and already understood it when I was 10), bulls can see red light (bees can't), they just can't discriminate it from other colours. After learning a bit more, I get that the word "colourblind" isn't only used for animals (and humans) who can't discriminate colours at all, but also for those that do so poorly from the point of view of us trichromats. Dichromats are, from our point of view, colourblind, although not as badly as monochromats. And as I understand it, most mammals (including bulls) are dichromats, old-world monkeys, apes and humans are trichromats, some nocturnal mammals and sea mammals are monochromats, having sacrificed colour vision for low-light vision. I expect that most people, when asked the question "Can cats/dogs/whatever see colour?", would answer "I don't know." PiusImpavidus (talk) 11:20, 3 September 2026 (UTC)

@~2026-47920-23 It's complicated, because it all hinges on what exactly you mean by color blindness. See Color_vision#Color_vision_in_nonhumans. Shantavira|^{feed me} 07:38, 3 September 2026 (UTC)

Yes, came here to say this. The term "colour blindness" is a holdover from when the science of vision was much less developed and the term gets used for anything from people who literally experience the world in greyscale to people who merely have poor fashion sense. It's not great when trying to extend the usage into animals. For the OP's questions, as an old fart from the time period in question, I think it was broadly understood that both dogs and cats didn't see colour or at least didn't see it well, but there were different contexts: cats are largely crepuscular/nocturnal; kids books that discussed myths about their vision would usually focus on debunking the idea that cats could see in complete darkness. They can't, but the myth was widespread because they do indeed need very little light to get by. As creatures associated with daytime, dogs' lack of colour vision was perhaps more noteworthy and jokes about that have persisted for a long time; they show up in Family Guy for example. Matt Deres (talk) 12:54, 3 September 2026 (UTC)

Wow, Lambiam hit some things right on the nail with those test-prep books. Shame on those publishing companies for not proofreading. If this is the mid-1970s, then the only way you would know cats were recently discovered to see color, is if you directly found those published papers in the literature. So I guess that means we rely on things like Encyclopedia Britannica to update with information. And Matt_Deres brings up a good point, I didn't even think about TV shows. ~2026-47920-23 (talk) 13:54, 3 September 2026 (UTC).

Shame on those publishing companies for not proofreading.

With no email and no web search, it could take the publisher considerably more time and effort than it would now. Even finding out who to ask was much less efficient, unless someone already knew. Not only that: they knew that the time and effort it would take most users of their books to fact-check the content was much higher still, so there was less financial incentive to avoid such mistakes. TooManyFingers (he/him · talk) 18:35, 3 September 2026 (UTC)

As a former (30+ years ago) school textbook editor, I would make two observations.

(1) Proofreading is a matter of catching printed accidental deviations from the intended final text: fact-checking takes place much earlier in the editorial process, and usually involves discussions with the author(s) to agree amendments or re-wordings.

(2) Texts for children are in most respects deliberate over-simplifications, because the world is more complicated than is useful for teaching new concepts initially; the same is true of books aimed at non-expert adults, just at a higher level.

Successive 'levels' of textbooks often 'creep up' on the latest current thinking, often following the historical progress of knowledge, and mindful that what we now think about something may well be refined or changed in the future.

This simplification of facts and concepts has sometimes been called Lies to Children. This reflects necessity, not deception: children have to be taught simplified/incorrect/'lying' versions of reality to prepare their minds for more advanced analyses that they would be too young to grasp: you don't try to teach six-year-olds about the Sun by presenting them with the Proton–proton chain, for instance.

Unfortunately, many adults who finished their education at a certain point wrongly think that they had then reached the 'acme of truth', and are resistant to further refinements and new discoveries. {The poster formerly known as 87.81.230.195} ~2026-43920-01 (talk) 02:02, 4 September 2026 (UTC)

Interesting, that lies to children article seems to list majority college-age examples. But for elementary school kids: growing up as a kid, I always thought winters is where Earth is farthest from sun and summers is where Earth is closest to sun in their orbit, but it's actually the opposite. So I always thought explaining seasons to elementary school kids is a hard subject. ~2026-47920-23 (talk) 11:04, 4 September 2026 (UTC).

It depends which hemisphere you're living in, northern vs. southern. ←Baseball Bugs ^{What's up, Doc?} carrots→ 12:48, 4 September 2026 (UTC)

I meant whether the Earth as a whole is in aphelion or perihelion. The hemispheres has to do with what direction they are pointing. ~2026-47920-23 (talk) 14:20, 4 September 2026 (UTC).

Summer and winter occur at opposite times of the year depending on whether you're in the northern or southern hemisphere. Perihelion occurs in January and aphelion in July. That's winter and summer respectively in the northern hemisphere, whereas they are summer and winter respectively in the southern hemisphere. ←Baseball Bugs ^{What's up, Doc?} carrots→ 15:55, 4 September 2026 (UTC)

Yes, to quote it directly "In the northern hemisphere, summer occurs at the same time as aphelion," which means it is farther from the sun, contrary to what we would think. ~2026-47920-23 (talk) 23:34, 4 September 2026 (UTC).

The difference from the mean distance is only around 1 percent, as I recall, so it's not nearly the effect that the earth's tilt on its axis has. ←Baseball Bugs ^{What's up, Doc?} carrots→ 00:02, 5 September 2026 (UTC)

That crack about the "acme of truth" makes me think of flat-earthers who chant "Water seeks its level !!!", which they learned as children, while denouncing the indoctrination of schools. —Antonissimo (talk) 18:34, 4 September 2026 (UTC)

"Water finds its level" is a very old saying. Good even for us round-earthers. :) ←Baseball Bugs ^{What's up, Doc?} carrots→ 18:45, 4 September 2026 (UTC)

The trouble is that they think only a plane can be "level". —Antonissimo (talk) 04:02, 6 September 2026 (UTC)

The concept of Spherical geometry would probably blow their minds. ←Baseball Bugs ^{What's up, Doc?} carrots→ 05:39, 6 September 2026 (UTC)

• The source is much debated and disputed, but the old saw goes that if you can't explain a scientific concept to a six-year-old/a barmaid/your grandmother in their level of language, you don't fully understand it yourself. How does this square with the Lies to Children ethos? -- Jack of Oz ^{[pleasantries]} 20:20, 4 September 2026 (UTC)

  It's precisely the point. That 'level of language' will not include Quantum chromodynamics or other advanced mathematics that are our actual current levels of relevant scientific understanding of the subject, because no six-year-old (and most grannies) do not yet have the foundational background necessary to understand them.

  Also, while a slightly more advanced understanding might be accessible to some six-year-olds, imparting it to them would take up a disproportionate amount of the limited time available in a normal pedalogical situation. {The poster formerly known as 87.81.230.195} ~2026-43920-01 (talk) 02:10, 5 September 2026 (UTC)

  I observe that the balance between informativity/specificity/technical-correctness and accessibility is what brings us the Simple Wikipedia versus e.g., Sage.

  the primary colours for bees are ultraviolet, yellow and blue

  I find it oddly comedic to have ultraviolet be listed as a colour, in hindsight. Modern cognitive neuroscience has decoupled conscious experience from its underlying physiology; "redness" is no longer just "cone cells responding to 450 THz waves", but "the feeling of seeing red", and qualia turned from a philosophical concept into a scientific question to be experiemented. By doing so, we kind of made the statement "colour of ultraviolet" null. 海盐沙冰 _{/ aka irisChronomia / Talk / Uploads} 15:11, 6 September 2026 (UTC)

September 4

What does GTL stand for in this diagram?

The best-fitting entry on the GTL disambiguation page is gas to liquid, but I'm not sure if that's what this diagram means by GTL. The file name seems to refer to a "GTL Program", but I don't know what that is. – MrPersonHumanGuy (talk) 18:57, 4 September 2026 (UTC)

It's a research programme - "DOE developed a forward-thinking program called Genomics: GTL (formerly Genomes to Life). The immediate goal of Genomics: GTL is to understand biological systems well enough to predict their behavior accurately with mechanistic computational models; the long-term goal of the program is to be able to develop microorganisms with capabilities for producing alternative energy sources, cleaning up the Cold War legacy of contaminated waste sites, and elucidating carbon cycling and sequestration.". DuncanHill (talk) 19:02, 4 September 2026 (UTC)

Now the context is clear. I came across it in the Earth system science article. – MrPersonHumanGuy (talk) 19:14, 4 September 2026 (UTC)

September 5

Untreated type 2 diabetes

A 77-year old woman with type 2 diabetes is in denial and refuses medical advice to change her diet. How much does this shorten her life span? JRSpriggs (talk) 22:22, 5 September 2026 (UTC)

Wouldn't that depend on the individual? ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:29, 5 September 2026 (UTC)

Of course. I was just hoping for an estimate which I could use to persuade her friends to stop enabling her. JRSpriggs (talk) 00:58, 6 September 2026 (UTC)

The Wikipedia Reference Desk rules state "Legal or medical advice is prohibited". If 'her friends' won't believe what qualified medical practitioners familiar with her case directly tell her/them, they will not be swayed by your second-hand reports of the opinions of anonymous, unqualified, uninformed responders on the Interwebs. {The poster formerly known as 87.81.230.195} 04:58, 6 September 2026 (UTC) ~2026-43920-01 (talk) 04:58, 6 September 2026 (UTC)

I assume the diagnosis has been made by a qualified physician; most symptoms of T2DM can also be due to other causes. Physicians should have access to statistical tables comparing the expected outcomes of treatment with those for untreated patients – at least my physician could supply me with this kind of information.

Expected benefits of treatment in terms of an increased quality of life will for some individuals be a more persuasive argument. Nature Reviews has a primer on type 2 diabetes with a section on quality of life (doi:10.1038/s41572-026-00687-w). It stresses the importance of the management approach being person-centred and broader than just treatment.  ​‑‑Lambiam 08:27, 6 September 2026 (UTC)

At her age, it's possible she doesn't like others telling her what to do. ←Baseball Bugs ^{What's up, Doc?} carrots→ 13:23, 6 September 2026 (UTC)

Like many of the people in the senior living facility we are in, she and her friends have memory loss. They have been told directly about the T2DM problem by the nursing staff, but they do not remember from one day to the next. In her case, she cannot remember for more than five minutes. The serving staff does not give her ice cream and certain other foods, but her friends subvert that by sharing theirs with her. I have tried telling them that this is wrong and violates the rules, but they are not swayed by that. So I want to be able to say that they are helping her shorten her life by such-and-such an amount. JRSpriggs (talk) 14:01, 6 September 2026 (UTC)

Or you could be a little more blunt, and ask those "friends" why they're trying to kill her? ←Baseball Bugs ^{What's up, Doc?} carrots→ 14:30, 6 September 2026 (UTC)

or as the poem says " "do not kill, but do not strive officiously to keep alive". Is it better to look after the friendship or to extend the life of someone losing their memory? Moral choices aren't always easy. NadVolum (talk) 17:54, 6 September 2026 (UTC)