Wikipedia:Reference desk/Archives/Science/2010 December 12

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December 12

squirrels

Do male squirrels rape female squirrels? —Preceding unsigned comment added by 66.66.92.152 (talk) 07:42, 12 December 2010 (UTC)

Possible, but very, very unlikely. The sexual behaviour of most non-human animals is governed by hormonal cycles of the females and their consequent results. Male squirrels would react to a female in oestrus and the female may or may nor permit any individual to couple with her. I believe it very improbable that a male squirrel would attempt to mate with a female that was not in oestrus. Furthermore given that the female squirrel is the same size and strength as a male squirrel the likelihood of a successful forced coupling to be almost zero. On a related point you should not assume that the level of noise and apparent resistance is indicative of an unwillingness on the part of the female. Domestic cats can make a hell of a racket when mating but that doesn't mean the queen is unwilling. Richard Avery (talk) 08:36, 12 December 2010 (UTC)

Squirrels have neither language to express consent nor a justice system to define rape. Female squirrels are unlikely to be aware of the causes of pregnancy, and therefore would have little reason to desire anything other than their instinctual urges during estrus. However, squirrels do use sexual behavior to establish dominance so from that perspective, even squirrel homosexual rape could be said to be common. Ginger Conspiracy (talk) 10:58, 12 December 2010 (UTC)

Well, that video is inconclusive to say the least. Let's just establish that there is a difference between mounting and rape. Rape it is not, but it has similarities with other species who symbolically mount peers to establish dominance, I'm thinking dogs. On another branch dairy farmers are able to identify cows in estrus by the way they mount other cows. I guess, with a certain mind-set and some distance, squirrels mounting could be mistaken for rape. Caesar's Daddy (talk) 11:47, 12 December 2010 (UTC)

Even an animal as large as a human finds it extremely difficult to restrain a squirrel. I can't imagine that a male squirrel could do it. Looie496 (talk) 01:18, 13 December 2010 (UTC)

Our article section Animal sexual behaviour#Coercive sex discusses apparent rape among dolphins, spiders, some birds, and some beetles. Our article Sociobiological theories of rape touches on the subject. Squirrels aren't mentioned. Comet Tuttle (talk) 19:37, 13 December 2010 (UTC)

Sunflower seeds changing colour

Resolved

We regularly bake soda bread which contains, flour, buttermilk, bicarbonate of soda, salt, sunflower seeds, rolled oats, sesame seeds and linseeds. I have noticed that when the bread is fresh baked and cut the sunflower seeds in the centre of the loaf have turned an emerald green (see photo). The sunflower seeds near the crust are the normal and natural beige colour. Over the course of the next 4 or 5 days the green sunflower seeds throughout the centre of the loaf gradually darken until they are black. Right, question, what has caused the seeds to turn green? And why do they continue changing colour to black? Richard Avery (talk) 11:35, 12 December 2010 (UTC)

The second question might be related to enzymic browning described at Browning (chemical process), although on second thoughts the heat from the baking may have de-natured the protein and thus stopped the enzymes from having any activity. 92.28.246.75 (talk) 15:10, 12 December 2010 (UTC)

Have you examined the green portions for the fibers and spores of fungus? Ginger Conspiracy (talk) 22:04, 12 December 2010 (UTC)

A quick Google reveals that this is a widely observed phenomenon, often blamed on the action of soda. The paper here, "Green Pigment Formed by the Reaction of Chlorogenic Acid (or Caffeic Acid Esters) with a Primary Amino Compound during Food Processing", looks likely to be relevant. William Avery (talk) 22:23, 12 December 2010 (UTC)

why do people say MSG is bad for you? Is it true?

why do people say MSG is bad for you? Is it true? —Preceding unsigned comment added by 82.234.207.120 (talk) 11:57, 12 December 2010 (UTC)

Although there is substantial public concern about MSG, there is no solid evidence of any connection between MSG and any serious long-term reactions. MSG is safe when consumed at usual levels by the general population. See Monosodium glutamate#Health concerns and Glutamic acid (flavor)#Research into health effects. Red Act (talk) 12:43, 12 December 2010 (UTC)

This is a pet peeve of mine actually, I've done quite a lot of research into it, partly because I love chinese food. Those articles linked above pretty much cover it and I completely agree with the conclusions. In my opinion, those who believe MSG is harmful seem to be people who tend to fall for the Appeal to nature fallacy, the same kinds of people who also think aspartame, GM, microwaves, mobile phones and EM radiation in general are somehow extremely "harmful". However in my opinion, fear of MSG is even more irrational since MSG is essentially a natural product and it is consumed by millions of Chinese people who don't seem to be suffering any great calamity as a result. Vespine (talk) 04:35, 13 December 2010 (UTC)

Those articles don't address another concern I've heard of (but am not endorsing), that MSG makes you hungrier, and therefore you eat more and become obese. While the Chinese don't seem to have this problem, that could either be explained by their metabolisms having evolved to handle MSG better, due to increased exposure, or simply the limited availability of large quantities of unhealthy food there, until recently. I would be interesting to know if increases in MSG usage in the US have corresponded with an increase in obesity. StuRat (talk) 07:02, 13 December 2010 (UTC)

I've never heard anyone claim MSG was bad for you. Some people claim to be sensitive to it, so they avoid it. thx1138 (talk) 23:36, 13 December 2010 (UTC)

No offense but you must have not looked very hard: msgfacts.net, msgtruth.org, banmsgnow.info, msgmyth.com, and that's just sites with MSG in the URL! Of course my personal opinion is that they're all complete rubbish, but there's no shortage of people who believe anything. Vespine (talk) 00:01, 15 December 2010 (UTC)

On psychology

I read the article on Reflex Action posted by Prakash on February 12,2010 as also the article on Defence Mechanism. I wanted to know are the main elements of Id, Superego and Ego propounded by Sigmund Freud capable of negating the inborn Reflex Activity Mechanism? In a sample I came across the Reflex Activity was nil? What are the reasons and How was it possible? —Preceding unsigned comment added by 59.93.87.116 (talk) 12:45, 12 December 2010 (UTC)

I only have a superficial grasp of psychology but I'll give it a go. Id, ego, and super-ego are elements of Freud's structural model of the psyche, AHA Ego psychology. In that article it states The clinical technique most commonly associated with ego psychology is defense analysis. Through clarifying, confronting, and interpreting the typical defense mechanisms a patient uses, ego psychologists hope to help the patient gain control over these mechanisms. So it sounds like that's part of the "theory" anyway, keep in mind these are all "models" so how well it translates to real world will undoubtedly vary. That's why it's not a universally accepted concept. Or my interpretation could be totally wrong ;) Vespine (talk) 03:34, 13 December 2010 (UTC)

Balls

Can a man who has had both testicles removed still experience orgasm? In my researched I found little information except several forum posts from people saying the prostate creates the majority of liquid expelled during ejaculation so a testicle-less man would still cum, but the cum would be devoid of semen. Is that true? 178.202.75.84 (talk) 14:29, 12 December 2010 (UTC)

I have no scientific data for you, but here is a relevant passage[1] from The Book of the Thousand Nights and a Night:

There are many ways of making the castrato; in some (as here) only the penis is removed, in other the testes are bruised or cut off; but in all cases the animal passion remains, for in man, unlike other animals, the fons veneris is the brain. The story of Abelard proves this. Juvenal derided the idea of married eunuchs and yet almost all of these neutrals have wives with whom they practise the manifold plaisirs de la petite oie (masturbation, tribadism, irrumation, tete-beche, feuille-de-rose, etc.), till they induce the venereal orgasm. Such was the account once given to me by a eunuch's wife…

Your post is nonsense. Cutting off the penis in no way makes a male a castrato. Mr. John Bobbit, though "bobbed," was by no means a castrato. He had the full benefit of male hormones. Edison (talk) 01:13, 13 December 2010 (UTC)

The book was, of course, written during an age when such misfortune was more common than it is today. Marnanel (talk) 14:36, 12 December 2010 (UTC)

This somewhat reputable looking volume says that there is a lot of variability — some castrated men can orgasm, some cannot. Age at castration seems to matter quite a bit. That seems to align with the anecdotal evidence I've seen via Google. As for the makeup of the ejaculate, it is by definition semen, but would not contain sperm. See Semen#Composition_of_human_semen. Sperm make up only 2-5% of human semen and are the only contribution from the testes. --Mr.98 (talk) 16:33, 12 December 2010 (UTC)

The mechanism by which castration might cause a lack of ejaculation is that the testosterone level would fall (since the testes also produce this), reducing libido. However, testosterone can be produced in other ways, and is shown by the fact that women have some, too. So, it might depend on the individual, whether they have sufficient extra-testicular testosterone production to maintain normal sexual function. StuRat (talk) 06:51, 13 December 2010 (UTC)

black slime on dripping taps

What's the black slime that grows around the spout of a dripping tap? I assume it's an alga of some sort. DuncanHill (talk) 15:27, 12 December 2010 (UTC)

Being black (as opposed to brown) I think it might be a bio-film caused by “manganese bacteria” See page 5 [2]. Whilst not considered to be a health hazard, I would suggest sterilizing it before drinking -as one would with any other type of tap water- with an equal part of a good malt.--Aspro (talk) 16:36, 12 December 2010 (UTC)

We also have an article on iron bacteria which mentions that these types of bacteria colonize the transition zone where de-oxygenated water from an anaerobic environment flows into an aerobic environment. A bit of lime de-scaler followed (after flushing) with bleach (well into the tap so that it reaches the washer seat), might do the trick. It is quite likely -I think- that this may be a periodic event, due to the water utility blending water from different sources. --Aspro (talk) 16:50, 12 December 2010 (UTC)

Thanks for the links and info. I never drink raw water anyway. DuncanHill (talk) 16:54, 12 December 2010 (UTC)

I'd call it mildew. It grows where it's damp. There is also supposed to be some common harmless black slime inside the pipes that is not killed by chlorine - I forget what that is called. 92.28.249.229 (talk) 18:08, 12 December 2010 (UTC)

Mildew normal grows on a nourishing substrait or a place where organic matter can accumulate. However, the black stuff enquired about, grows at the out pouring of water. That which grows 'inside pipes' is an anaerobic form of iron and/or manganese bacteria. Indeed, they do so, by being able perform a reduction of manganese oxide and thus can grow without the need for atmospheric oxygen. As you say, they (anaerobic and aerobic) can resist the low levels of chlorine, because they form a protective film. This anaerobic slim, however, ends up inside the pipes. It does not form slime deposits at the taps. As any meerkat will tell you – It's simples!--Aspro (talk) 18:51, 12 December 2010 (UTC)

The mildew in my bathroom grows on the grout between tiles and other places wuthout any nourishment but dampness. 92.15.5.93 (talk) 01:04, 13 December 2010 (UTC)

Oh, so things like soap and dead skin cells and bacteria and funguses and other things does not count as "nourishment"? --Jayron32 04:10, 13 December 2010 (UTC)

I get it at the ceiling - none of those things there. I do not get it on the glass of the shower cubicle I expect because it dries rapidly. 92.29.117.8 (talk) 11:18, 13 December 2010 (UTC)

An increased manganese level in your water supply could lead to cognitive developmental disabilities (see article). ~AH1^(TCU) 03:43, 18 December 2010 (UTC)

Nutrition

I have a box of 5 freshly baked donuts. I could eat one a day for 5 days, or I could eat them all today and have none for the following four days. As far as enjoying them, the latter strategy is preferable because they taste much better fresh. In terms of my body's absorption of bad fats and too much sugar, is there a nutritional benefit in spreading them out over the five days? Or would it be better to them all at once? Staecker (talk) 21:19, 12 December 2010 (UTC)

The correct answer depends on body mass index and other factors that are often only available from a physical examination which is one of the reasons that the Reference Desk is unable to give you medical advice. If we were able to based on an aggregate profile, however, we might recommend physical exercise as an alternative to donuts.[3] Ginger Conspiracy (talk) 22:49, 12 December 2010 (UTC)

I am not requesting medical advice. I'm just asking something about how the body metabolizes fats and sugars. Compare alcohol: drinking a lot at once gets you really drunk, while drinking little by little very slowly doesn't. Is there a similar (or opposite) effect with fats? If the answer depends on BMI, then how does it depend? (High BMI means ...? low BMI means ...?) Fearing some "medical advice" objections, I originally included the following disclaimer, but decided against it. I guess I was wrong, so here goes: This is totally hypothetical, and in no way a request for medical advice. I am not diabetic or overweight or allergic to donuts or etc etc so nobody needs to worry that your response will cause or prevent a 15 minute spiral into overeating as excessive as it is brief. I currently have 0 donuts in my home, and, while I do live near a donut shop, it is raining and I have two little kids in bed so I won't be buying any donuts anytime soon. They do not deliver. Staecker (talk) 00:18, 13 December 2010 (UTC)

In that case, is there any way you can preserve the donuts for shipment to the nearest area with a famine problem? Would it be better to sell the donuts and donate the money to an organization working to fight obesity? The extent to which it is better nutrition for you to do so is related to your body mass index, economic factors determining your ability to obtain more food, heat, shelter, and other necessities, how much physical exercise you get, and the physical and mental health of your community. Assuming the answer to the nutrition question is that you should eat the donuts, try cutting them into quarters and you'll have small deserts for 20 meals. If, however, this presents a crumb hygiene problem, you might keep them whole and buy enough celery and broccoli to make a reasonable donut salad meal out of each, being careful to prevent feeding insects, rodents, and other parasites with the crumbs. Ginger Conspiracy (talk) 04:31, 13 December 2010 (UTC)

My guess is that if you eat them all at once, more of the bad stuff is going to pass straight through you because your digestion is more overwhelmed with fat. The sugar would have less bad effect on your teeth also. 92.15.5.93 (talk) 01:08, 13 December 2010 (UTC)

I agree with your last point but disagree with the first one. We are able to digest lots of fats at once, certainly 5 donuts worth. One way we know this is that undigested fat in stool (steatorrhea), which we get when eating undigestable fats/fat substitutes, causing the infamous anal leakage problem, doesn't happen from just eating lots of fats. StuRat (talk) 06:42, 13 December 2010 (UTC)

My guess is that if you eat 5 donuts today you won't be able to resist the cravings and eat some more after a couple of days. 71.101.41.73 (talk) 03:54, 13 December 2010 (UTC)

Eating five donuts at once is going to give you a big Blood Sugar spike. Provided you're not a diabetic, this probably isn't the end of the world, but there are bad things associated with big swings in blood sugar levels. I think they'll be a diminishing returns effect too. Do you really think that fifth donut's going to be better if you eat it right after 4 other donuts, even if it's fresh? I'd find that last donut pretty disgusting, and would much rather have it for breakfast on the fifth day, rather than for a mid-afternoon snack on the same day I ate four other donuts. That's just me though. Buddy431 (talk) 04:29, 13 December 2010 (UTC)

I agree with the last two responses. The problem with eating them all at once is that your body will then expect that again the next day, hence the cravings. Sugar and fats are addictive. StuRat (talk) 06:28, 13 December 2010 (UTC)

Buy lots of fresh fruit 'n' veg and fill up on those as much as you like without any guilt. 92.29.117.8 (talk) 11:21, 13 December 2010 (UTC)

Boy, a lot of people decided to lecture you on obvious stuf rather than answer the interesting question. I've always heard than a single gorging is better, because you don't absorb as many calories as if you space it out. I, too, would be interested in reliable sources or papers that discussed this. 86.161.208.185 (talk) 10:30, 14 December 2010 (UTC)

I know of a diet that's based on eating slowly, and chewing the food longer, and it is supposed to make you loose weight. Now I don't know if its claimed efficiency is due to the fact that giving your body the time to digest makes it take in less fat (that would support the option of eating all the doughnuts at a time but slowly, rather than eating each one separately and fast), or if it is simply that eating slowly gives you the time to acknowledge you are eating and "prepares" your body. For it is known that if you eat -even a lot- over a very short period of time, you are still hungry afterwards: it takes about 20 minutes to get the digestive system ready. Therefore eating slowly would allow you to eat less food before you actually sense satiety, and consequently reduce the amount of food you eat, a very good way to diet ! OK, what I wrote is a bit confused, but see if you can figure some sense out of it ^^ ! RiverGirl (talk) 13:54, 14 December 2010 (UTC)

Compound identification

Can anyone recommend some sources dealing with historical chemical compound identification? When were IR and NMR spectroscopy first adopted widely? What techniques were used before those? 149.169.174.230 (talk) 21:43, 12 December 2010 (UTC)

Please see Analytical chemistry, Spectrum analysis, Infrared#History of infrared science (maybe Crookes tube and Anders Jonas Ångström belong in that list too; not sure about Bunsen), Nuclear magnetic resonance#History, Chemical test#Inorganic tests, Gravimetric analysis, and Titration. Ginger Conspiracy (talk) 22:57, 12 December 2010 (UTC)

There are several tests for functional groups amines, carboxylic acids, ketone, aromatic ring systems make all of them!..... Than you get the molecular mass by ebullioscopic (Cryoscopic constant) best in camphor. Than you create some derivatives like hydrozones or nitroesters or pikrates or thioureates ... make a lot of them. Measure the melting point of all of them and than have a look in the library. If you have similar numbers go back to the lab and make the same derivative from the compound (of the shelf) you think you have. Make a mixture of the now known substance derivative and your derivative and than you measure the melting point of the mixture if this is the same like the melting point of the pure substances you have the identical substances. If you you have done this and you find nothing in the library make a reaction to cleave of a part of your molecule. There are countless chains shortening reactions or oxidation reactions which get rid of some parts of your unkown molecule. Than start over with the first point on the list above. The described methods are the ones of the late 19th century, but they work. --Stone (talk) 23:00, 12 December 2010 (UTC)

(ec) There are many small nuggets of historical information scattered throughout the various relevant articles:

• Analytical chemistry
• List of chemical analysis methods
• History of chemistry
• Category:History of chemistry
• History of chromatography
• Infrared spectroscopy
• Nuclear magnetic resonance#History

Chemical tests were widely used before the advent of spectroscopy and other instrumental techniques. Flame tests are one early example,

Organic compounds used to be synthesised (from scratch or a well-characterised precursor) and their physical properties (melting point, optical rotation, reaction with various other substances) compared to a sample from nature to see if they were identical. I think aldehydes and ketones used to be converted to hydrazones to make them crystalline, then their melting points were compared.

All these articles have good references in them.

Ben (talk) 23:18, 12 December 2010 (UTC)

IR spectroscopy only became widely used for compound identifucation after the Second World War, and NMR is even more recent. A major tool has always been elemental analysis, although degradation and derivatization methods as described by Stone and Ben also have a long history in organic chemistry. Physchim62 (talk) 23:28, 12 December 2010 (UTC)

Pre-electronic chemical tests are usually called Wet chemistry by chemists in the field. While strictly speaking, it could refer to any aqueous-phase chemistry, in practice chemists use it to refer to non-electronic analytical techiniques, such as, for example, flame tests, precipitation tests, pH tests via indicators, etc. etc. --Jayron32 23:39, 12 December 2010 (UTC)

See proton NMR. ~AH1^(TCU) 03:41, 18 December 2010 (UTC)

Planet Brightness

Why do the solar-system planets glow brightly as if they were at a very high temperature? Similarly, why does the earth’s moon glow like a fluorescent lamp?

I think this effect has to do with the apparent brightness of the planet or moon as seen from earth, and its apparent area as seen from earth. I think that as distance increases, apparent brightness decreases more slowly than apparent area. Therefore the amount of light (number of lumens) per unit of apparent area increases with distance. Is this explanation correct? Diatom 173.189.136.110 (talk) 23:05, 12 December 2010 (UTC)

The planets are lit and heated mostly by the Sun, light from which is both reflected and absorbed; see Albedo. But some of the planets have hot cores with heat remaining from their formation. The geothermal energy of the earth is one example, and all of the planets may have warm solid cores at higher gravity and load-bearing pressures in an insulated thermal equilibrium with the much larger solar energy. Ginger Conspiracy (talk) 23:52, 12 December 2010 (UTC)

The heat isn't just from the formation, some of it is from radioactivity. --Tango (talk) 00:16, 13 December 2010 (UTC)

And tidal forces. StuRat (talk) 06:23, 13 December 2010 (UTC)

Heat doesn't enter into it because none of the planets is hot enough to radiate light as a result of thermal incandescence. I am referring solely to reflected sunlight. I think I didn't express myself sufficiently clearly in my original post. -- Diatom.173.189.136.110 (talk) 16:30, 13 December 2010 (UTC)

The power decreases with the square of distance and area decreases linearly with distance, so you are correct that the brightness per unit area increases. I don't understand your question, though. The planets don't glow, they reflect sunlight. That means that, roughly speaking, they appear to be the same colour as the sun, which is determined by the sun's surface temperature. The same applies to the moon. (Due to the human eye being specialised to distinguish colours close to that of the sun, we can actually see noticeable colour differences, but the overall difference in the spectrum is pretty small.) --Tango (talk) 00:16, 13 December 2010 (UTC)

Um, that's not correct -- area decreases with the square of distance. Objects actually maintain a constant apparent brightness as they get farther away. Stars and planets don't start to look dimmer until they are so far away that they are too small for the eye to resolve -- before that point they only look gradually smaller but equally bright. (It's a little weird to think that from, say, the orbit of Neptune, the Sun looks like a very small circle but is still so bright that you can't look steadily at it without harming your eyes -- but it's true.) Looie496 (talk) 01:12, 13 December 2010 (UTC)

Looie496 writes "Stars and planets don't start to look dimmer until they are so far away that they are too small for the eye to resolve -- before that point they only look gradually smaller but equally bright." However, as the planets move around the sun, their distance from earth varies. Their perceived brightness varies as a resu.t. -- Diatom 173.189.136.110 (talk) 07:14, 13 December 2010 (UTC)

Our Luminosity article discusses some of this. The Radiative flux, F, decreases with distance from the light source:

$F={\frac {L}{4\pi r^{2}}}\,$

See also our Apparent magnitude article. WikiDao ☯ (talk) 00:15, 13 December 2010 (UTC)

Thanks for the replies to my question about the brightness of planets and the moon. What I meant by “glow” was the bright appearance that would not be perceived by an astronaut standing on the planet or moon. If an astronaut on the moon experienced that glow, it would seem to him as if he stood on a plate of ground glass that was brightly lighted from beneath. Also, the planets as seen from earth appear to be gas heated to incandescence, like a star, which is not the case. To carry this a bit farther, as the distance of a planet increases, would its perceive brightness increase continually? Would it become visible in the daytime sky? If it was far enough away, would it be as bright as the sun (albeit only a dot in size)? Diatom 173.189.136.110 (talk) 01:44, 13 December 2010 (UTC)

You may be referring to sunlight reflected on the moon by Earthshine. The very faint lunar atmosphere can be ionized by solar and cosmic radiation, but that is not visible to the human eye. Ginger Conspiracy (talk) 04:42, 13 December 2010 (UTC)

I am rdeferring to sunlight reflected from planets and the moon. -- Diatom. 173.189.136.110 (talk) 06:37, 13 December 2010 (UTC)

The amount of light (number of lumens) per unit of apparent area does not increase with distance, so there is no tendency towards infinity luminosity at great distances. Dbfirs 08:03, 13 December 2010 (UTC)

I think that what Diatom is talking about is simply the fact that the planets "look luminous" because, when we see them, we always see them against the contrast of the black night sky. Compare the "luminous" appearance of the Moon at night with its appearance in the daytime when it's seen against the lighted blue sky. It just looks bright because your visual system is adjusted for the darkness. Similarly, a building illuminated by a narrow shaft of sunlight on a dark cloudy day may "look luminous", while the same building with an equal amount of light on it on a bright sunny day does not. Your visual system is adjusted for the surroundings, not the building. See optical illusion for some examples of such effects. --Anonymous, 09:45 UTC, December 13, 2010.

OK Anon. The moon in the daylight sky was a good example. It is approximately the color that would be expected from reflected sunlight, with maybe a bit of color change due to absorption of some colors by the moon’s surface. And as you indicate, the brilliance of some planets at night would be due to the iris being wide open. I thik we have also established that the perceived brightness of an object decresses with its distance. I think this matter has been laid at rest, unless someone has a further comment. Diatom. 173.189.136.110 (talk) 16:52, 13 December 2010 (UTC)

The act of observing an object affects the object

I am certain that this is somewhere in Wikipedia, but I have no idea how to find it. In a nutshell, someone said that the act of observing an object (eg atom, animal, etc.) affects the thing being observed even if it does not know it is being observed. Can someone point me to a relevant artical? I am not clear how this is even possible (especially for somethng that is non-living) 99.250.117.26 (talk) 23:47, 12 December 2010 (UTC)

Observer effect comes to mind.Vespine (talk) 23:52, 12 December 2010 (UTC)

There is a "measurement effect" in quantum mechanics which results from the fact that, physically speaking, measurement involves copying some aspect of the thing you're measuring (such as its position) to another location (such as magnetized zones on a computer hard disk or neuronal firing patterns in your brain), and in quantum mechanics the actual physical process of copying has noticeable side effects. There's no such effect for large objects at room temperature, because they are constantly exchanging heat with the environment, and that also counts as copying and triggers the same effect whether or not a human scientist is doing a measurement at the time. There are other "observer effects" in other fields of science that are sometimes (wrongly) conflated with the quantum one. -- BenRG (talk) 00:18, 13 December 2010 (UTC)

Heisenberg's uncertainty principle. 92.15.5.93 (talk) 00:57, 13 December 2010 (UTC)

No, not the uncertainty principle. The right article is the observer effect (physics). 71.101.41.73 (talk) 03:50, 13 December 2010 (UTC)

Note that there are plenty of ways you can observe an animal or person or macroscopic event without necessarily affecting the outcome (e.g. observing at such a distance that the observed cannot perceive you). There are some macroscopic situations that are analogous (imagine trying to behave "naturally" while being followed around by a camera crew), but it's really the same thing as the quantum effect. --Mr.98 (talk) 13:02, 13 December 2010 (UTC)

Because the weird world of quantum mechanics seems to be what reality is made of, there have been many invocations of QM concepts in explaining the every day macroscopic world. In general, you should take these with a very macroscopic grain of salt. If you were to observe a group of camels from a satellite, you would have exactly zero effect on their behavior. --Sean 22:16, 13 December 2010 (UTC)

(That image was actually taken from a powered paraglider, by George Steinmetz.) -- BenRG (talk) 23:22, 14 December 2010 (UTC)

It seems to me that the act of observing (on any scale) affects the observer (i.e. his/her perception of reality) rather than the observed (i.e. the observed's reality (assuming that the observed is unaware of the scrutiny it is under; non-living things can not be "aware" so this becomes a moot point)). 99.250.117.26 (talk) 04:30, 14 December 2010 (UTC)

Well, yes, but in quantum mechanics there is a definite effect by which a "measuree" can detect that it is being scrutinized, regardless of the details. Two specific examples are quantum key distribution and the quantum Zeno effect. -- BenRG (talk) 23:22, 14 December 2010 (UTC)

See Schrödinger's cat. ScienceApe (talk) 14:24, 14 December 2010 (UTC)