Wikipedia:Reference desk/Archives/Science/2015 April 28

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April 28

Parrots and chillies (probably about the 15th question on this topic)...

So, it's fairly common knowledge that (most?) parrots have a natural tolerance for the capsaicin in chilli peppers - and a parrot can eat something like a habanero, the seeds, placenta and all, without the slightest apparent distress.

What I was curious about this time though - was how high this tolerance actually goes. Would a parrot be able to eat one of the superhot chillies, with a heat in the range of the millions of Scovilles? I've heard it said that parrots are immune to capsaicin, but OTOH, some people have said that it just affects them somewhat less than humans. --Kurt Shaped Box (talk) 00:52, 28 April 2015 (UTC)

The whole question is closely related to the evolution of mutualisms between birds and plants, e.g. frugivory, zoochory, and seed dispersal. It's not just parrots - virtually all birds have virtually no aversion to capsaicin, at least compared to mammals. The idea goes like this, speaking teleologically as not-quite-correct short hand: Plant species usually "want" their seeds to be dispersed, to deal with environmental heterogeneity and uncertain growing conditions, as well as to get a better mix of mates in sexual reproduction. Mammalian digestive tracts tend to be more damaging to seeds than bird digestive tracts. So, some plant species deal with the problem by adaptation to tougher seed coats that can survive passing through a mammal. Others, like piper_(genus) Capsicum, forego the resistant seed, and instead try to make sure only birds eat their seeds, so that they will survive the easier digestive tract. This way, dispersal is more likely than without a mammal deterrent, and it is also farther ranging, giving plenty of selective pressure to plants that can make compounds that mammals avoid and birds don't mind. Of course modern artificial selection and breeding programs have made things like the ghost pepper, which probably wouldn't have evolved so hot on its own. But that's all just context and background.

As to your actual questions - I think capsaicin is mostly invisible to the bird taste receptors. Here's a few scholarly papers that relate to the topic, I might be able to find better references tomorrow [1] [2]. Here's an interesting one that discusses behavioral effects of capsaicin on birds- when injected subcutaneously... [3]. SemanticMantis (talk) 02:28, 28 April 2015 (UTC)

Ok, capsaicin binds to vanilloid receptors, specifically one called TRPV1. This paper [4] says:

"In contrast, chicken TRPV1 is insensitive to capsaicin (Jordt and Julius, 2002)"

This paper [5] says:

"Interestingly, birds have a TRPV1 ortholog even though they do not seem to taste 'hot' sensation when they eat hot peppers."

-- But now I'm out of my element. My slightly-educated-guess is that the bird TRPV1 ortholog just doesn't accept capsaicin, so it's not really a an issue of "tolerance" as we normally think of it - the birds just don't notice any burning in the first place, for the evolutionary reasons I outlined above. @Wnt: might be able to fill in some more detail on the biochem stuff. SemanticMantis (talk) 14:20, 28 April 2015 (UTC)

It looks like you have the situation well in hand, but I went to Jordt and Julius [6]. They find that the chicken vanillinoid receptor is resistant to activation by even 200x the EC50 in mammals (look at Figure 1D - clean as a whistle) But in Figure 2 they find a tiny tendency to increase activation at low pH and corresponding inhibition by the antagonist at lower pH: "perfusion of cVR1-expressing oocytes with a high dose (50 μM) of capsaicin produced a small and slowly developing enhancement of proton (pH 5.5)-evoked currents (Figure 2A). Second, pH 4.0-evoked currents were partially blocked by 20 μM capsazepine (Figure 2B), a competitive capsaicin antagonist that has also been shown to attenuate native heat-evoked responses in chick DRG neurons" This doesn't directly tell whether capsaicin could make heat seem just a little hotter, but it takes a huge amount of it to do anything at all. Now, I can't tell you for sure about the superhot chillies unless someone actually did the experiment, because it is possible, for example, that there's some capsaicin-like compound present at maybe 1% of the level of capsaicin that mammals don't notice but which is hot to parrots. In biology you never really know until you do the experiment. But a good guess would be that yes, they may well be immune. Wnt (talk) 15:34, 28 April 2015 (UTC)

Dolphin rape

So I've watched a video which claimed that Dolphins were dragging decoy humans with tracking devices into caves when they decide to drag it underwater with their penis. Could this be a predatory instinct most people call it dolphin rape but I believe it is a predatory technique — Preceding unsigned comment added by Dystopia in a bag (talk • contribs) 07:49, 28 April 2015‎

Rape is a thing that a person can do. Scientists don't usually call any animal behavior "rape". That is a human concept, and when we apply it to animals, we risk being unscientific. I mean sure, bed bugs seem to have a rough time - traumatic insemination may seem sort of like rape to us, but that's the only way they reproduce, and calling it rape is not scientifically valid. The scientific thing to do is just describe the behavior, without ascribing any motive or intent. SemanticMantis (talk) 14:24, 28 April 2015 (UTC)

See Anthropomorphism#In_science for more on what SemanticMantis is talking about. --Jayron32 17:45, 28 April 2015 (UTC)

One of the exceptions to this is that ethologists often refer to duck matings as "rape". They can be very aggressive affairs with the male (perhaps several) holding the female's head under water repeatedly. However, I agree with the above that this is a rather anthropomorphic term.DrChrissy ^(talk) 17:49, 28 April 2015 (UTC)

Well, the good ethologists don't call duck copulation "rape" ;) I've probably seen more duck mating than most of us, and indeed it can look violent and aggressive. But for all we know the ducks love it. Or they just really want to hold out for the strongest drake, or any number of other things. Nobody calls it rape when hundreds of drones chase a virgin queen bee into the sky [7], but that's probably because more most people it's harder to empathize with bugs. Here's a video of dragonflies mating, played with classical music as a beautiful affair, a "perfect dancing couple" [8]... neglecting to mention that one or both parties may die in the process, or survive with punctures to the eye, etc. [9]. My point is, sexual conflict plays out in many ways in the animal (and plant, and fungal) kingdom, and it can seem odd to us -- but when we apply value-laden human-centric terms to their behavior, we do a disservice to both them and our scientific understanding. SemanticMantis (talk) 18:20, 28 April 2015 (UTC)

Hey SemanticMantis, I am with you 100% on this. I'm not sure why this "rape" label stuck (a bit) with ducks, but it really is a misnomer.DrChrissy ^(talk) 18:33, 28 April 2015 (UTC)

All good, and you're right, it is used... So I had a look around a bit to see what kinds of serious science I could find that talks about "rape" in the animal kingdom this [10], from 1980, is the worst offender I could find. I'm fairly confident that abstract would have to be worded in a much more neutral manner to get published today. Mr. Thornhill should be trouted for referring to male Panorpa as "rapists" and considering the females "unwilling" -- how could he possibly know the volition of a scorpionfly?! Anyway, yes - "rape" can be used as a sort of casual shorthand for describing certain types of copulation, but that doesn't mean it should be. While I have no problem occasionally indulging e.g. in the teleological framing of evolution (as I did, with caveat, just above in the post about parrots), playing fast and loose with rape seems needless, tone deaf, and uncouth to me. SemanticMantis (talk) 18:36, 28 April 2015 (UTC)

BTW, the OP very correctly termed it something that "most people call it" and made no indication they thought otherwise. But now that we've corrected something they got perfectly correct in the first place, can anyone answer their actual question? I've got no idea, myself, but if the behavior has been seen in the wild as a method of predation, that would support the OP's assertion. Matt Deres (talk) 14:06, 29 April 2015 (UTC)

Hi Matt. I think what has happened here is that editors have been replying saying the term is incorrect. This is related to the question as the crux of this is what motivation/s the dolphin was experiencing at the time of the behaviour. The first thing to note is that we have not seen the video. It would be little more than speculation for anyone to suggest what the dolphin is doing without having seen the video. Yes, the behaviour might be motivated by abberant sexual desires. Yes, the behaviour might be motivated by predatory desires (though not necessarily instinct as the OP suggested), although what prey do (individual) dolphins take that are as large as a human? A third possibility is that the dolphin might have been attempting to assist the diver. There are several reports of this type of behaviour in dolphins. In short, I doubt very much you will get a definitive answer to this, especially without seeing the video.DrChrissy ^(talk) 14:36, 29 April 2015 (UTC)

I don't disagree with any of that. What I object to is the apparent decision for all involved to not answer a valid question in favour of a knee-jerk response to a term they don't like. Even if it's completely a given that the term is inaccurate, it's widely understood - and the OP even specified they already knew it was only a term that gets thrown around inaccurately. Harping about the terminology served no purpose. Matt Deres (talk) 10:30, 30 April 2015 (UTC)

Boiling

Which uses less power; 2,300 watts for 2 minutes, 1,500 watts for 15 minutes? This is not homework I'm trying to work out how to boil eggs efficiently but I'm a maths moron and can't do it myself. Thanks for your help! — Preceding unsigned comment added by 39.176.65.28 (talk) 16:02, 28 April 2015 (UTC)

Just multiply them together: 2,300 watts for 2 minutes is 4,600 watt-minutes, and 1,500 watts for 15 minutes is 22,500 watt-minutes, so the latter is a lot more energy (though only 65% of the power).--Shantavira|^{feed me} 16:17, 28 April 2015 (UTC)

I'm not sure that the OP's methods will yield a meaningful answer: bear in mind that, once raised to a certain temperature, eggs' protein continues to 'cook' even when no further heat is applied – my suspicion is that the 15 minutes will produce extremely hard boiled eggs. {The poster formerly known as 87.81.230.195} 212.95.237.92 (talk) 16:23, 28 April 2015 (UTC)

On the other hand, 2 minute eggs will likely be very runny. --Stephan Schulz (talk) 16:29, 28 April 2015 (UTC)

• Just to clarify a bit, Power (physics) is a measure of how much energy is consumed in a given unit of time. The unit of power is the watt, so 2300 is more power than 1500. The first scenario is more power. However, if we're asking energy, since power is energy per time, that's simple algebra to say that energy is power multiplied by time. Shantavira did that math for us all, and the second scenario consumes more energy. Just make sure to get the terms correct, it does matter so we all speak the same language. --Jayron32 17:41, 28 April 2015 (UTC)

• As far as how to boil eggs using the least energy total, that's going to depend on many factors, such as if the pot is covered or not. (A well insulated set-up would favor cooking the egg slowly, while a poorly insulated set-up would make it more efficient to cook the egg quickly (provided you had the electrical power to do so). It's also possible to cook eggs with just sunlight, or perhaps using some electricity and some sunlight (such as to preheat the water). Just starting with a room temperature egg and water, instead of cold, will make a difference. StuRat (talk) 20:04, 28 April 2015 (UTC)

I think you've wasted more energy asking the question. Electric rates are about $0.10 per kW*hr. 2.3kW for 1/30 of an hour is less than a penny. 1.5kW for 1/4 of an hour is about 4 cents. Put the eggs in, boil the water on high and after it starts boiling take them off after 10 minutes. Works everytime. --DHeyward (talk) 22:50, 28 April 2015 (UTC)

Not only that but you have identified the correct technique to minimise electricity usage however much power or insulation you have available, at least in normal atmospheric conditions. Bring to boil as quickly as possible, leave in boiled water til cooked. Greglocock (talk) 01:43, 29 April 2015 (UTC)

Not sure "bringing to a boil as quickly as possible" applies to a covered pot, at least with gas. With a small pot on a gas burner on high, a lot of that heat goes around the pot instead of into it. The OP listed power as watts, which implies an electric stove, so there the difference might be on placing the pot on a small stove element or a large one where the maximum power could be applied. Again, the large one would waste a lot of energy heating the air outside the pot. StuRat (talk) 18:53, 29 April 2015 (UTC)

Yeah I was thinking the same thing as StuRat. Bringing to the boil as fast as possible wouldn't necessarily be the best strategy. You have to consider how the losses from bringing to boil slower compare to the potentially greater losses from bring it to boil faster due to the somewhat indirect application of heat. For something like induction or microwave cooking (not that it's generally the best idea to boil eggs in the microwave), it's likely that bringing to boil faster will be more effective. For normal resistive eletrical element, provided the pot is fits all the way on the element it's probably better to bring to boil faster too. For gas, it'll probably depend on the burner design and pot, and won't necessarily be better. (Of course there's also the question of efficiencies at higher outputs, again for all the eletrical ones I think the higher output will be more efficient if it's any different. Gas it's less clear.) One thing which was hinted at above but doesn't seem to have been clearly specified, if you only care about powerenergy efficiency, what you actually want to do is to bring to boil, then turn off the element if at all possible. If your eggs aren't suitable hardness by the time the water isn't really doing anything, then may be you need to leave it a bit longer before turning off the element. In fact, depending on your preference, pot insulation and other factors, you may not need to bring all the way to boil, although realisticly getting the right temperature will be annoying enough that most will just bring to boil. Well actually most will just continue to simmer without turning off the heat until they're nearly done and then take out the egg or discard the water, but turning off earlier is at least something you can probably get right easily with a bit of practice. (Alternatively you could find a way to use the water.) Nil Einne (talk) 19:14, 29 April 2015 (UTC)

Good point about not needing to bring it to a boil. Since that uses extra energy to cause the water to undergo a phase transition, it's rather inefficient to heat with boiling water, and even moreso if steam is allowed to escape (which will happen, to some extent, even with a lid). If there's any way to avoid it and still get the desired result, that is likely to be more energy efficient. StuRat (talk) 17:14, 1 May 2015 (UTC)

Where can I find a good skeptical review of the "quantum magnetic resonance analyzer"?

A friend of mine mentioned getting a "checkup" with this device. I knew already from the name that it was pseudoscientific quackery, and a bit of web searching confirmed that it consists of a hand-held "probe" that basically just confirms that someone is holding it, and that the system prints out essentially random medical "reports" that are weighted according to the gender and age of the "patient".

There are plenty of these machines for sale on Amazon.com, and I took the time to review one of them.

What I have found so far:

• Quackwatch mentions the basic class of devices, without mentioning it by name (I've mailed Dr. Barrett to ask him to mention it specifically).
• Discover Magazine has a blog post or two that show videos of people who demonstrate that if you plug a resistor into the machine instead of the probe, it does its "gee whiz" scan and diagnoses the resistor with diabetes or kidney stones or whatever.
• The New Zealand Advertising Standards Authority found that therapeutic claims made by the product are unsubstantiated.
• The pamphlet for the machine is full of completely incoherent pseudoscience.
• I can't find any mention of it on fda.gov or cdc.gov

In summary, the machine is clearly a fraudulent device when evaluated by anyone who knows anything about medicine, biology or physics, and I want to conclusively debunk it, but before I put in the effort, I'm sure someone must have done so in the few years that it's been on the market. but I can't find a reliable source which succinctly says this. Do any of you know of one? --Slashme (talk) 18:42, 28 April 2015 (UTC)

I assume you have read the series of posts on the device in the Neuroskeptic blog since you mention that source. I doubt there is any more detailed analysis of the clearly bogus device(s). Many different devices are marketed under that generic "science-y" name and even the articles you linked above don't necessarily refer to the same device; compare [11] with [12]; and note that the device in the NZ ASA ruling doesn't have "resonance" in the name. So given that it is impossible to even nail down what any of these device (or claimed phenomenon on which they are supposedly based) is, it would be impossible IMO to find any definitive debunking. Abecedare (talk) 19:07, 28 April 2015 (UTC)

I agree that it's total bunk, but the resistor method might also "disprove" Body_fat_percentage#Bioelectrical_impedance_analysis, by calling some combo of electronic components "obese". StuRat (talk) 19:58, 28 April 2015 (UTC)

It works best if the recommended treatment is followed to cure whatever illness is diagnosed, see here. Without that recommended treatment, using the device can be extremely dangerous, see also here. Count Iblis (talk) 21:28, 28 April 2015 (UTC)

I take "nocicebo" claims with a grain of salt. My feeling is that in that BBC article, the propaganda payload is that people who object to the infrasound generated by some wind turbines are just nuts (I don't live in Britain, but my impression AFAIK is that offshoring wind turbines is a contentious issue, because it removes noise from commoners' homes at the expense of ruining the lovely views of the beachfront properties); the rest is some hastily thrown together window dressing. For example, getting people to notice altitude symptoms isn't some kind of evil suggestion, just routine observation. Frightening people to death is sort of real (cortisol) but uncommon; it relies on confirmation bias more than anything else. A rare exception is rip tides, which indeed can tire out and kill the overly direct thinker (unless you're on the lee of an island in a current or something ;)) but are generally harmless to those who think them harmless. Wnt (talk) 22:35, 28 April 2015 (UTC)

Nocebo, incidentally. Tevildo (talk) 05:59, 29 April 2015 (UTC)

That infrasound is perceived subconsciously by many people is quite well proven and often leads to feelings like anxiety. The only question about wind turbines is whether the infrasound they produce is of a type and loud enough to do that. And I know my mother was easily able to hear ultrasonic sounds well outside the normal hearing range so I would be very cautious about put downs about what people say they experience like that. Dmcq (talk) 11:54, 29 April 2015 (UTC)

Oh, as for the machine, it's like 99.9999% sure to be the most transparent fakery. That said, it is within the capabilities of Chinese researchers to assess which species of fungus is in a live tree using terahertz radiation. I suspect that terahertz has vastly more potential to measure DNA sequence and protein binding than is presently realized, and someone with advanced knowledge of the field might indeed be able to duplicate some of the alleged applications of this quack device. But... no. Wnt (talk) 22:39, 28 April 2015 (UTC)

Check Quantum Xrroid Consciousness Interface. I once posted something about this device on the reference desk but was ridiculed, so I gave up. I have nothing more to say on this device, but there is something similar that I have experienced for myself and it works. My homeopath connects an electrical device to various different fingers, and connects an allergen to the device. There is a meter on it which immediately shows how allergic you are to that allergen. I went there after having had all the modern medical allergy blood tests done, and this machine was uncanny in its accuracy, without my having told the homeopath what I was allergic to. I then asked her to test my son and it showed the same accuracy. There is still a lot to be discovered in the 'field' (no pun intended) of electromagnetism and its effects on the body (which generates EM itself) and I suspect these quack machines use basic principles with varying degrees of success. Perhaps one day there will be a convergence with science. Please save the 'medical advice' lectures as I just wanted to give my 5 cents on the matter. Sandman1142 (talk) 11:19, 30 April 2015 (UTC)

Sadly, you're going to get ridiculed again...your answer definitely ain't worth 5 cents.

This reference desk is about SCIENCE. Science has proven, multiple times and in a dozen ways that (for example) homeopathy doesn't work. So your homeopath is likely either severely mislead - or is a lying, cheating, scumbag quack. In either case, this person is not to be trusted to deliver an accurate diagnosis of allergies either with or without some bizarre contraption. Wikipedia demands that we back extraordinary claims with extraordinary evidence...there is no scientific evidence of these machines actually working - nor is there any reason to suspect that they could...so your experiences count for nothing here. We have very good science and a mountain of WP:MEDRS references to back the fact that homeopathy doesn't work - and despite years of searching by ardent enthusiasts, not one single Wikipedia-acceptable document has showed up that shows that it does.

That is significant when writing here for the reference desk: Wikipedia's "supreme court" at WP:ARBCOM have ruled that homeopathy is a pseudoscience and that what we write is required to be from a position of mainstream scientific consensus. Without WP:MEDRS-quality sources backing what you say, homeopathy is not to be given credence...so please don't do that here.

People believe that all sorts of nonsense provides uncanny accuracy - even when we know for 100% sure that they are nonsense. Astrology is a great example...people who believe in it will swear up and down that their horoscopes are uncanny in their accuracy - yet serious studies of it show that it's bunkum. In one classic experiment, a class of students was each given a "personalized" horoscope and asked to rate how accurate it was...they almost all came back with high positive scores...then it was revealed that in fact, they'd all been given the exact same reading. Yeah - it's bullshit.

You believe that the machine works because you want it to work - and because the so-called homeopathist is good at Cold reading (check the article) and sounds authoritative and expert. Frankly, you're not looking at the science - you are simply lacking the critical thinking skills needed to see through the deception. This is especially bad because (I presume) this is costing you actual money - and because it may prevent you from getting actual medical advice when you need it - which is something that's killed a LOT of people - some people have been convicted of manslaughter because they took the advice of a homeopathist with a sick child who died due to lack of medical care.

Several of these so-called diagnostic machines have been opened up and shown to contain utterly meaningless circuitry that's designed just to produce an interesting-looking show of flashing lights, dials and other readouts for the quack to "interpret" for you. One notable way these things 'work' is by measuring the resistance of the skin...you can use a $20 multimeter to do the same thing...when you do that, the reading clearly depends on how hard you press down with the probes - whether you pinch the skin or not - whether the skin is slightly moist or oily. You can get almost any reading you want by doing that. This article goes into some detail about what these machines are - and how they are marketed. It's a scam...and you just fell for it, hook, line and sinker! SteveBaker (talk) 13:48, 30 April 2015 (UTC)

Only saw this reply now. You are so blindly driven by pure science that you fail to see alternatives. I know brilliant allopathic doctors who admit that certain homeopathic remedies do NOT have any allopathic counterpart and some have even taken to providing alternative healthcare. There are even medical aids that pay for a few homeopathic remedies, and as science understands alternative healing better and better, so shall the industry. My son had severe eczema and went to several dermatologists who gave him all sorts of steroid creams which damaged his skin and never did cure the eczema. We then found a good homeopath who made up some special pellets for him, and he was cured within a week. This was after a year of hell and taking extremely strong medication. However, nothing I say here has any meaning for you, so no need for any more argument. And no I do not believe in astrology but I do have an open mind, unlike some. Sandman1142 (talk) 06:21, 5 May 2015 (UTC)

What we need to realize is that the nocebo effect is far more powerful than the placebo effect alone, and the two in combination with each other work like magic. So, if I'm a homeopathic doctor and like Steve explained above, a patient comes in, I give a false diagnosis, like that the patient is feeling tired because his kidneys are not working ok., I can see that using my magical device. This gives rise to a powerful nocebo effect. Then I prescribe a magical cure, which then takes away part of the nocebo response and may actually do something to alleviate the original complaint via the placebo effect. Then when the patient returns, I do another test using my magical device, and lo and behold, the kidneys are working a lot better than last time. The patient looks a lot happier, the original complaint is almost gone. Count Iblis (talk) 18:51, 30 April 2015 (UTC)