Wikipedia:Reference desk/Archives/Science/2019 August 16

= August 16 =

Pigeon Toes
Having lived and working in London for many years there is a quandary that has been bothering me for some time. I have noticed that the vast majority of the Pigeons have less that the naturally prescribed number of toes. It is unclear if this is a birth defect or if this is due to recurrent injury or another cause. I would assume that there is some Pigeon fancier’s association which would be tracking this sort of thing but have not been able to find anything through my searches. Please would you be able to provide the following information. A.	What is the cause of the missing toes? B.	What is the cure to resolve this problem and C.	Is this a common feature in other major cities in the world. Thank you. Anton 81.131.40.58 (talk) 10:11, 16 August 2019 (UTC)


 * Theories seem to be A) Falcon attacks; B) Cats; C) Pigeons getting their feet caught in things like wire mesh and losing a toe while trying to break free. So that's the answer to your first question. Answer to the second is keep your cats indoors and maybe don't have things outside that a wild animal could get stuck in, though not much to be done about the falcons. Answer to the last question is yes.. Someguy1221 (talk) 10:25, 16 August 2019 (UTC)


 * This makes me wonder if pigeons lose their toes like lizards lose their tails: . That is, as a defense mechanism (better to lose a toe than their life.). SinisterLefty (talk) 11:05, 16 August 2019 (UTC)


 * This is a commonly observed effect in UK pigeons nationwide and is seen as one of the differences between verminous city pigeons and the elegant rural pigeon. I live in a village and although we have many pigeons, they are plumpy well-fed and have dainty well-formed toes. In contrast to the small city nearby, and even their pigeons are in better shape than those in the larger cities.
 * It's often put down to inbreeding, as city populations are often relatively insular. I don't believe the wire mesh claim, as our village shops have an ongoing battle with the pigeons (it's such a joke that the local Facebook groups have banned pigeons as the one unmentionable topic). Wire mesh and pigeon guards are rife, which the pigeons seem to regard as cat-proof nesting verandahs instead, and cheerfully nest inside the wire. Yet there's no fot damage evident. Andy Dingley (talk) 11:27, 16 August 2019 (UTC)
 * Footless Urban Pigeons are unable to groom head and neck feathers that the bill can't reach, and with unrepaired plumage they are disadvantaged in flight, are less able to keep warm, waterproofed and free of parasites, and are less attractive as mates. Beside mechanical causes, it is reported that deformities may be hereditary. DroneB (talk) 12:58, 16 August 2019 (UTC)


 * This pigeon rescue site says it's a condition called "stringfoot", which is caused by urban birds using non-natural nest materials that get tangled round the feet and cause constriction and then infection. PaleCloudedWhite (talk) 13:01, 16 August 2019 (UTC)


 * This is a huge problem, . 2A00:23C5:3186:E600:3D9B:C5C7:2662:1431 (talk) 14:27, 20 August 2019 (UTC)
 * For those seabirds maybe. Regarding city pigeons, I doubt they're an endangered species. ←Baseball Bugs What's up, Doc? carrots→ 15:16, 20 August 2019 (UTC)

Brief Observations on Common Mortars...
I have a citation:



So far I have found two parts, and details of a third:


 * Volume ?? pp. 227-253 (Commons file)
 * Volume 21 pp. ?-383
 * Volume 22 pp. 1-26 (Google Books)

How many parts were there in total? What is the missing metadata? Are the other part(s) online? Andy Mabbett ( Pigsonthewing ); Talk to Andy; Andy's edits 10:57, 16 August 2019 (UTC)


 * I wonder if the first one was actually from the 1842 reprint, which placed Totten's essay near the end of the 256-page issue . Someguy1221 (talk) 11:04, 16 August 2019 (UTC)
 * Perhaps. The two files start with the same sentence ("During the progress of operations..."). Table LXV (for example) on page 7 of the Google Books file is the same as table LXV on page 236 on Commons. However, the final paragraphs of the file on Commons do not match the final paragraphs of the Google Books (vol 22, pp. 1-26) file. The Google Books file ends with "...half as strong as this sandstone", but the Commons file continues (p. 252) beyond that. So what was "Vol. 21 pp. ?-383"? Andy Mabbett ( Pigsonthewing ); Talk to Andy; Andy's edits 11:31, 16 August 2019 (UTC)

I have now been referred to another part:


 * Volume 26, pp.145-147 (continued from p.26) Archive.org

this contains the material that is in "Volume ?? pp. 227-253" but not "Volume 22 pp. 1-26", to which I referred in my previous comment. Andy Mabbett ( Pigsonthewing ); Talk to Andy; Andy's edits 12:02, 16 August 2019 (UTC)


 * The 1838 edition of the same work linked above is here but it only gives the pp. 227-253 section that you have already found (not much help I'm afraid). Alansplodge (talk) 17:38, 16 August 2019 (UTC)
 * Journal of the Franklin Institute, Volume Volume XXI (Jan-Jun 1838 has a French article translated by Totten in monthly instalments, but not anything by Totten himself (I have scrolled through the whole thing). Alansplodge (talk) 18:19, 16 August 2019 (UTC)

What is the difference between allotropy and polymorphism (materials science)?
Reading both linked articles does not clear that up for me. (It says allotropy is a form of polymorphism, but does not give an example of non-allotropy polymorphism.) Tigraan Click here to contact me 13:26, 16 August 2019 (UTC)
 * Both articles state that allotropy only refers to chemical elements. PaleCloudedWhite (talk) 13:32, 16 August 2019 (UTC)
 * Polymorphism refers to a situation where two different physical phases of the same substance exist in the same state of matter. That is, if a substance exhibits two different solid forms, it exhibits polymorphism.  Allotropy is just polymorphism in a chemical element.  For example, carbon has three common allotropic forms: diamond, graphite, and fullerene.  However, compounds also exhibit polymorphism, for example the compound calcium carbonate has multiple solid forms: calcite and aragonite.  One of the most famous fictional examples of polymorphism is Ice-9 from Kurt Vonnegut's classic novel Cat's Cradle.  -- Jayron 32 13:48, 16 August 2019 (UTC)
 * So... if I understand correctly, it's only allotropy when you change the arrangement of chemical bonds? In which case ice phases are not allotropes (since it changes hydrogen bonds, not the O-H covalent bonds), right? Tigraan Click here to contact me 14:05, 16 August 2019 (UTC)
 * No, no. Isomerism is when you change chemical bonds, for example the difference between cyclopropane and propene.  Allotropy only refers to chemical element differences.  Furthermore, allotropy can refer to both differing arrangements of actual chemical bonds (like ozone and dioxygen) AND different arrangements of the atoms/molecules (like in white phosphorus vs. red phosphorus).  Water is NOT a chemical element, so differences in arrangements of water molecules is NOT allotropy.  It would be a form of polymorphism.  The different phases of solid ice are known as "different phases" or "crystal phases" or something like that, if you didn't want to use the word "polymorphism".  But they are definitely not allotropes.  -- Jayron 32 15:36, 16 August 2019 (UTC)

Alumen
What is the loss of alumen? — Preceding unsigned comment added by Ganesh dhar dwivedi (talk • contribs) 14:14, 16 August 2019 (UTC)
 * It's when your supply runs out. ←Baseball Bugs What's up, Doc? carrots→ 14:38, 16 August 2019 (UTC)
 * (ec)In which context did you encounter the phrase "loss of alumen" ? All I can find is the latin or portuguese word. https://en.wiktionary.org/wiki/alumen. Or did you mean loss of albumin? This article talks about "natural alumen", in case it is relevant. --Lgriot (talk) 14:42, 16 August 2019 (UTC)
 * @Lgriot what they mean is this: alum

type I renal tubular acidosis
I don't understand why hyperchloraemia occurs in type I renal tubular acidosis. A bit of googling and several youtube videos later and I'm still perplexed! I know the answer is something to do with those pesky alpha intercalated cells in the collecting ducts. From what I understand, there is a failure to excrete H+, leading to acidaemia (easy enough to understand). I know that there is a HCO3-/Cl- exchanger on the basolateral membrane of the alpha intercalated cells. In RTA type I there is reduced bicarbonate re-absorption into the blood (due to reduced H+ excretion) so I'm guessing this would prevent the excretion of chloride via this HCO3-/Cl- exchanger. However, I also note there is another Cl- channel on the basolateral membrane that allows chloride back into the blood from the cell anyway, so I don't see how chloride can be excreted even when the HCO3-/Cl- exchanger is working normally! I hope this question makes sense. Many thanks, RichYPE (talk) 19:54, 16 August 2019 (UTC)
 * our article doesn't mention symptom hyperchloraemia, and hyperchloraemia doesn't mention this cause (but that is not so much a surprise, if there are so many cause for hyperchloraemia, all won't be in the article). Gem fr (talk) 20:52, 16 August 2019 (UTC)
 * One obvious thing is, if less H+ are out, for electrical balance either more (anything)+ (Hypokalemia is mentionned) or less (anything)- also must be. Cl- is the most obvious candidate Gem fr (talk) 20:52, 16 August 2019 (UTC)