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May 2

Intelligence of magpies

Something I remember reading about once. You know how magpies like to bury pieces of food for later retrieval? Apparently some magpies will only pretend to hide the food if they notice that another magpie is watching them, because they figure that the other bird will just steal it as soon as they're gone. So they hold it in their mouth or swallow it (birds can easily regurgitate things), take it away and try to lose the observer. Apparently this is a sign of significant intelligence that very few animals (and not all humans) possess? What's the name for it, anyone know?

Yaknow, it's like "I know that he will do this because I would do the same to him if he were in my place and I know that he also knows this - but I also know that he can be fooled". That thought process. Knowing that another individual has intelligence, the same as you do. --Iloveparrots (talk) 20:50, 2 May 2022 (UTC)[reply]

Or learning through bitter experience. --←Baseball Bugs ^{What's up, Doc?} carrots→ 21:27, 2 May 2022 (UTC)[reply]

There is actually a thing though. The ability to speculate what another individual knows, or doesn't know. There's an experiment they can do with people. Put two people in a room with a scientist and an object in front of them, ask one person to leave the room while the scientist hides the object somewhere. Then ask the second person where the first person will start looking for the hidden object, when instructed once he/she returns to the room. Apparently quite a few people answer that the first person will start looking in the place where the scientist hid the object, despite them not being there to witness this and having no way of knowing. This apparently demonstrates something (the correct answer is supposed to be "they'll start looking from the place where they last saw the object"). --Iloveparrots (talk) 23:38, 2 May 2022 (UTC)[reply]

See Theory of mind in animals. AndyTheGrump (talk) 23:41, 2 May 2022 (UTC)[reply]

Thanks, i knew the concept, not the name. Greglocock (talk) 23:43, 2 May 2022 (UTC)[reply]

If its not in the Deception in animals article, then it should be. A cursory scan didn't find anything, but its a fairly long article. --2603:6081:1C00:1187:910F:9107:F1C7:15E1 (talk) 23:35, 2 May 2022 (UTC)[reply]

The section Deception in animals § Tactical deception mentions common ravens and Eurasian jay preferentially caching their food out of sight of other birds, but not deceptive fake-caching. --Lambiam 07:59, 3 May 2022 (UTC)[reply]

Here we are told that black-billed magpies hold the food to be deposited in a cache in a small pouch under their tongues, and that after hammering the ground to form a small hole into which the food can be deposited, they may move the food to another location if other magpies are watching. --Lambiam 07:59, 3 May 2022 (UTC)[reply]

May 4

Soft oranges

I've seen non-frivolous webpages that claim that a soft spot on an orange indicates rotting/fungi. Is it really that serious? Seems a bit extreme to throw out any citrus that's not firm all over. Could it be something else, like dehydration? Imagine Reason (talk) 16:02, 4 May 2022 (UTC)[reply]

Can you please direct us to a link we can assess. "I've heard that" or "I've seen that" is not a reliable source, and if we're going to provide you with additional reliable sources, we're going to need to see where you are reading this information. --Jayron 32 16:08, 4 May 2022 (UTC)[reply]

Of course not all soft spots are caused by infection, if you bruise a citrus fruit enough you can make it soft. That said, infections are relatively common and many manifest as soft spots. http://ipm.ucanr.edu/PMG/C107/m107bpfruitdis.html#SOFT 64.79.120.146 (talk) 18:25, 4 May 2022 (UTC)[reply]

Per 64.79, risk assessment would tend to say that the value lost by throwing away a harmless, but soft, orange is much less than the value gained by not getting food poisoning. Which is to say that while most soft oranges are probably fine to eat, some are very much not, and 1) if you're checking the orange at the grocers, don't buy it if it is soft, because why spend money to take that risk and 2) if it's in your fruit bowl at home, and it's gone soft, the cost of an uneaten orange may be miniscule compared to the potential cost (in either real doctor's bills or in the value of "pain and suffering") of food poisoning. --Jayron 32 18:34, 4 May 2022 (UTC)[reply]

The old adage, "If in doubt / Throw it out." --←Baseball Bugs ^{What's up, Doc?} carrots→ 20:56, 4 May 2022 (UTC)[reply]

May 5

Paralyzed individuals

Curious: if a person is paralyzed, do they maintain functioning of the genitals / sex organs? Specifically, penis/testicles, vagina, anus, etc. In other words, can/do they have sex (in the traditional way we think about sex) ... and can/do they maintain bathroom / excretory functions (urine, defecation, etc.)? Can they get erections, ejaculate, have orgasms, etc.? Menstruate? I assume each individual is different ... as each injury is different. But, generally speaking, I refer to patients paralyzed "entirely" or paralyzed "from the waist down". Thanks. 32.209.55.38 (talk) 17:43, 5 May 2022 (UTC)[reply]

It really depends on the type and nature of paralysis. Some such individuals may retain partial or total control over some or all of those functions, and others may not. This paper, for example, describes the impact of spinal cord injury on sexual function in men. That's just one cause of paralysis, and one function you are asking about. It's really an extremely varied question you are asking, so general that it is impossible to speak in general terms. There are many causes, many types, and many effects of paralysis. It's just too broad of a topic. --Jayron 32 18:19, 5 May 2022 (UTC)[reply]

We do, however, have Sexuality after spinal cord injury as a Wikipedia article. WP:WHAAOE it seems. --Jayron 32 18:21, 5 May 2022 (UTC)[reply]

Note that the menstrual cycle is governed by the estrogen and progesterone levels in the blood, not the nervous system, so spinal cord injuries don't have any significant impact on it. Hormonal contraceptives work by "overriding" this with exogenous hormones, and with the onset of menopause this hormonal cycle stops, which is why menstruation ceases. (Hmm, pregnancy after spinal cord injury might be an article worth having.) --47.147.118.55 (talk) 03:36, 7 May 2022 (UTC)[reply]

The animal with the fastest hair growing rate

Hi, we know that human hair usually grows about 1/2 inch a month.
My question is what is the species with the fastest hair growing rate? (including fur for example).

Thanks — Preceding unsigned comment added by 77.124.10.130 (talk) 22:07, 5 May 2022 (UTC)[reply]

there is very little usable information I can find, but I would look for literature on the rodent whiskers growth rate. Dr Dima (talk) 22:28, 5 May 2022 (UTC)[reply]

aha! found it. "whisker growth was linear and occurred at 1 mm a day in the mouse and 1.5 mm a day in the rat" [1] . That's about 1 3/4 inches per month for a rat whisker Dr Dima (talk) 22:38, 5 May 2022 (UTC)[reply]

still doesn't mean that's the fastest growth rate across all animals though Dr Dima (talk) 22:45, 5 May 2022 (UTC)[reply]

May 7

Previously frozen Acid (Yogurt) Whey, for fermentation

I have been making yogurt, using the cold start method, as described at and several other sites, using Fairlife Ultra-filtered milk (whole) or Kirkland/Costco Ultra-pasteurized (2%) milk, with a commercial active-culture yogurt as a "starter". I strain the excess whey, to produce "Greek" style yogurt. I understand that "acid whey" from yogurt can be used, at home, to ferment vegetables, among other uses. I have been storing excess whey in the freezer, hoping to use in the future.

My question: Does the freezing of acid whey, and the subsequent, (albeit gentle and slow, in the refrigerator) thawing process disturb the ability of the whey to ferment vegetables? Summer vegetable season is approaching, here in the Southeastern US, but I don't want to attempt to ferment cabbage, cucumbers and such, only to have food rot/go to waste. Frozen, active-culture yogurt "starter" revives and works fine, for new yogurt batches, but I'm not sure about the whey, for fermentation of vegetables. Somewhat "whey" over my head! Not here on a daily basis, please ping, if possible. Thanks very much, Tribe of Tiger ^{Let's Purrfect!} 03:57, 7 May 2022 (UTC)[reply]

If the fluid is salty enough, the desired fermentation will take place regardless of the liveliness of any lactic-acid producing bacteria in the fluid, since there will be enough on the vegetables to start the process. The salt inhibits the growth of other, unwanted microorganisms. The point of using whey, if I understand correctly, is that there is already a substantial amount of lactic acid present, giving the fermentation process a head start before unwanted growth spoils the food. This blog post argues that salt is better than whey anyway. If you are in an experimental mood, you might experiment with using your whey with different amounts of added salt. --Lambiam 08:45, 7 May 2022 (UTC)[reply]

In this article the authors added L. plantarum by various methods to ice cream being produced and tested which fraction survived the successive production steps. The method closest resembling the whey situation was the addition of "prefermented skim milk". Then, assuming the "Log" in "Log cfu/g" in Figure 2 stands for the common logarithm (base 10), the reported reduction in viable L. plantarum organisms by the steps of "aging" for 24 h at 4°C followed by freezing for 15 min at −5°C was by about a factor of 4. I would expect (but am not sure) that most of the damage is done at the moment of freezing, and that keeping the stuff, once it is frozen, in that state for an extended period at a relatively steady temperature will not make much of a difference. --Lambiam 19:26, 7 May 2022 (UTC)[reply]

Lambian I didn't realize that L. plantarum was already present on vegetables...duhh. The blog is helpful, from a "practical use" view point. I like to drink whey, adding a few dashes of salt. I know it is acidic, by the flavor. (Should unearth my Ph test strips). The "ice cream" article was over my head, thanks for providing a simplified summary. So, frozen whey may still assist the fermentation process, if a boost is needed, depending on home temperature. I will experiment with whey and/or salt. You have been extremely helpful, thank you so much! Tribe of Tiger ^{Let's Purrfect!} 21:34, 7 May 2022 (UTC)[reply]

Deciphering a product label

I am trying to decipher a product label. This is the product: [2]. Specifically, the 320-count bottle. (I think that you have to specifically click on the 320 Count Selection Box, located over to the right of that page.)

[Bullet 1] One of the labels says Serving Size 5 Capsules

[Bullet 2] One of the labels says Active ingredient (in each capsule): Psyllium husk approximately 0.52 g

[Bullet 3] One of the labels says One serving of this product has 1.8 grams of this soluble fiber (that is, soluble fiber from psyllium husk)

OK ... so ... the third bullet point says:

One serving of this product has 1.8 grams of this soluble fiber (that is, soluble fiber from psyllium husk)

Since Serving Size 5 Capsules ... the above statement can be restated as:

5 Capsules of this product has 1.8 grams of this soluble fiber (that is, soluble fiber from psyllium husk)

Dividing by five ... the above statement can be restated as:

1 Capsule of this product has 0.36 grams of this soluble fiber (that is, soluble fiber from psyllium husk)

This last statement doesn’t seem to square with Bullet Point Number 2 up above. So, can someone please clarify? What am I missing? I am trying to determine how much of the “medicine” or of the “product” is in each single capsule. In other words, if I take one capsule, I am getting ___ (how many grams) ___ of daily fiber / psyllium husk from that one capsule? Thanks. Joseph A. Spadaro (talk) 21:53, 7 May 2022 (UTC)[reply]

Why would you assume that P. husk is entirely made of soluble fiber? Obviously, it includes other things as well. Anyway, this isn't medicine any more than a banana is medicine (I'm sure there's some website that claims it is). Imagine Reason (talk) 22:44, 7 May 2022 (UTC)[reply]

The FDA has approved several health claims for this product that have not been approved for bananas; see Psyllium § Human health. You may be able to obtain funding from distributors of bananas to examine whether they offer comparable health benefits. --Lambiam 06:51, 8 May 2022 (UTC)[reply]

I can confirm the correctness of your computation. If 1 serving (5 capsules) contains 1.8 grams of mucilaginous fibre, 1/5th of a serving (1 capsule) contains 1.8/5 = 0.36 grams of the good stuff. So this amounts to 0.36/0.52 × 100% = about 70% of the husk. According to this web page, the remaining 30% is insoluble fibre, which isn't bad for one's health either. --Lambiam 07:07, 8 May 2022 (UTC)[reply]

User:Lambiam ... thanks for your helpful reply. That website link was very helpful. I guess the part that confused me the most was that the label mentioned "active ingredient". The term "active ingredient" -- in these labels -- apparently refers to the psyllium husk, and not to the soluble fiber itself. I would have thought that the "active ingredient" would (should) refer to the fiber itself ... the 70% of the husk that is soluble. And I would have thought that the 30% of insoluble fiber was not particularly helpful or "active". (So, I guess I was incorrect.) Hence, the source of my confusion. Thank you again.

Now, a follow-up question, if I may. That website states: The Academy of Nutrition and Dietetics recommends that women aim for 25 grams of fiber per day, and men should consume 38 grams of fiber per day. So, let’s just assume -- hypothetically, for purposes of this conversation -- that a male obtains all of his daily fiber from these capsules, and from no other source whatsoever. Which below would be the better / more appropriate calculation?

* Calculation A -- daily goal of 38 grams per day / 0.52 grams of active ingredient (psyllium husk) per capsule = 73 capsules per day needed

* Calculation B -- daily goal of 38 grams per day / 0.36 grams of soluble fiber per capsule = 106 capsules per day needed

Again, just hypothetical. I'm really just trying to figure out the correct math, behind all this. Thanks! Joseph A. Spadaro (talk) 19:24, 8 May 2022 (UTC)[reply]

Based purely on the statement I'd go with A. The husks are all fibre, a mix of soluble and insoluble fibre. Neither type is digested. However, psyllium is unusual in its low percentage of insoluble fibre. The research the advice is based on may have involved more balanced diets with a much higher percentage of insoluble fibre, and it is not obvious that the results can be extrapolated to an extraordinary diet in which psyllium husks are the sole source of fibre. To be on the safe side, one might therefore even argue for C -- daily goal of 38 grams per day / 0.16 grams of insoluble fiber = 238 capsules per day. --Lambiam 21:54, 8 May 2022 (UTC)[reply]

May 8

How does a baby toucan fit into its egg with that beak?

Question as topic. You've seen the size of their beaks, I guess. I know a macaw that has a crooked beak because he was apparently too big for his egg, so I'm not sure how toucans manage with their proportionally larger beaks... --Iloveparrots (talk) 01:24, 8 May 2022 (UTC)[reply]

This article says "Toucan babies do not have a large beak when they hatch from the egg but it is wide and heavy compared to other baby birds". This youtube video also shows newly-hatched toucans have pretty small beaks relative to the proportions seen in adulthood. JoelleJay (talk) 02:29, 8 May 2022 (UTC)[reply]

Same with pelicans. Shantavira|^{feed me} 08:16, 8 May 2022 (UTC)[reply]

Maximum hair length in human male

Can I ask how the hair length of a (white, northern European, if that makes a difference) man is determined if he just lets his hair grow out? I have had long hair for about 15 years and it has never grown further than about 2.75/3 feet. Is there some preset length for each individual person before it stops growing? I think it's true that women can grow their hair longer (have seen women with knee or shin length hair but never men), but I'm not sure. 146.200.128.101 (talk) 07:31, 8 May 2022 (UTC)[reply]

See Maximum hair length.--Shantavira|^{feed me} 08:18, 8 May 2022 (UTC)[reply]

I wonder how many individual strands, if any, would eventually fall out naturally, assuming no hair-loss disease? --←Baseball Bugs ^{What's up, Doc?} carrots→ 08:36, 8 May 2022 (UTC)[reply]

All of them, eventually. Each hair follicle has a cycle (not co-ordinated with neighboring follicles) of hair growth, 'regression', and resting/shedding (in which the no-longer growing hair is eventually pushed out by the emergence of a new hair). The durations of each of these stages can vary greatly between individual people, and as one's overall head of hair comprises an aggregate of hairs at all of them, the duration of the individual's average growth stage will determine their average/maximum hair length. OP, see also Human hair growth.

My own white, northern European male hair hasn't been cut for more than 2¹/₂ years, and seems to be peaking at around 16": 4–5 decades ago in my youth I could manage about 20", so (being a Metal fan) I envy the OP. His question about the maximum cannot really be answered for him except by his own observations, because it varies greatly between individuals, and seemingly over an individual's lifespan. {The poster formerly known as 87.81.230.195} 90.208.88.97 (talk) 13:02, 8 May 2022 (UTC)[reply]

x-ray equipment

I have sometimes wished I could x-ray a piece of electronics or the like. I'm sure x-ray equipment (even like what the TSA uses) is expensive and maybe regulated, and DIY'ing it has to be dangerous, especially since the only natural source of x-rays I can think of is neutron stars ;). I suppose I could ask my dentist to x-ray something (no idea if they would accomodate), but is there a more general way to get access to this sort of thing without spending a fortune? No idea if the equipment itself is financially approachable for a maker space that has stuff outside the typical hobbyist budget (laser cutter etc.), but not anything like an industrial lab. Thanks. 2601:648:8202:350:0:0:0:4671 (talk) 20:09, 8 May 2022 (UTC)[reply]

I strongly doubt just anyone can X-ray stuff without medical/dental supervision. You could accidentally zap people, pets etc. This Japanese Ministry of the Environment article says "X-rays have high penetrating power and travel several tens to hundreds of meters in the air." Clarityfiend (talk) 04:11, 9 May 2022 (UTC)[reply]

Obviously there are dangerous radiation levels at least inside the test chamber, but x-rays are frequently used for non-medical purposes, such as electronic component and welding inspections, to say nothing of luggage examination at the airport. Yes there would (I hope) be some fairly serious regulations about building and operating such machinery, but medical personnel would usually not be involved. I doubt there are doctors on hand at airport security when they x-ray your carry-on bag. They also (foolishly) use backscatter x-ray on humans there, and there were even attempts to deploy it on trucks for pedestrian traffic. I'm imagining some kind of shielded chamber where you put in a test sample and press a button. It doesn't sound inherently more dangerous than a thermal or microwave oven. Just don't put your hand inside while it's running, etc. 2601:648:8202:350:0:0:0:4671 (talk) 05:37, 9 May 2022 (UTC)[reply]

May 9

What is the difference between live and neutral in AC current?

The title explains it all.

~~Sorry the answer is probably obvious but I'm a very stupid man.~~ WikipediaNeko (talk) 05:04, 9 May 2022 (UTC)[reply]