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December 13

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Burp, hiccup, sneeze at the same time

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Is it physiologically possible to simultaneously burp, hiccup, and sneeze all at the same time?

... and still live? and not choke to death? :p

and less seriously:

What would happen if you burp, hiccup, sneeze, cough, growl, snort, sniffle, and chortle at the same time? :P -- œ 00:25, 13 December 2010 (UTC)[reply]

well you can't inhale and exhale at the same time so I'd say no, it's not possible to do some of those things at the same time. You can definitely interrupt a burp with a hiccup, but you can't do them simultaneously. Vespine (talk) 00:51, 13 December 2010 (UTC)[reply]
I did that today.. interrupted a burp with a hiccup (which made a funny sound).. then I sneezed almost immediately afterward.. it was the most strangely enjoyable sensation. -- œ 02:00, 13 December 2010 (UTC)[reply]
Thank you for sharing. Cuddlyable3 (talk) 13:24, 13 December 2010 (UTC)[reply]
My pleasure. I'll make sure I keep the refdesk updated of any recent developments. -- œ 13:41, 13 December 2010 (UTC)[reply]
On a similar theme, the OP and others might be amused by our brief entry on Roland the Farter. What it doesn't make clear is that the elements of his triple feat were performed simultaneously. 87.81.230.195 (talk) 16:11, 13 December 2010 (UTC)[reply]

Two questions:

1) My understanding is that a nuclear reactor is set off by a chain reaction, whether fission or fusion. According to this [1], one neutrino carries as much energy as a fast-served tennis ball (!). If a neutrino were to hit a piece of matter in a nuclear reactor, could this cause the chain reaction to start?

2) Theoretically speaking, would it be possible that neutrinos or a similar subatomic particle could be possible for atom decay? Perhaps our understanding of quantum physics is all wrong - perhaps quantum tunneling isn't actually a particle breaking its own physical laws, rather just that it received help from another unseen particle. Thoughts? Magog the Ogre (talk) 02:33, 13 December 2010 (UTC)[reply]

Neutrinos do not normally interact with other matter; a single neutrino would not be able to "set off" a nuclear chain reaction as you describe. Consider that you are currently bathed in neutrinos right now, they are racing straight through you, and yet scientists have to go through some pretty extensive and exotic methods just to "catch" a few neutrinos per day. As to the second question, it is always possible that everything we know about everything is completely wrong; for all I know even I don't even exist, and I am merely being imagined by someone else. At some level, you need to trust existing theories about how the universe works, given that a) the existing theories are accepted because they pretty much work and b) no one has proposed anything better yet. Of course, part of science is being willing to ditch old theories in the face of new evidence. But we don't ditch existing theories on the possibility of future evidence which has not yet materialized. --Jayron32 02:41, 13 December 2010 (UTC)[reply]

There is evidence that solar neutrinos might influence the decay rates of radioactive isotopes on Earth.[2] While it might still be controversial[3] I have no reason to doubt it or to believe it breaks any known physical laws. Ginger Conspiracy (talk) 04:47, 13 December 2010 (UTC)[reply]

Altering decay rates of isotopes isn't exactly the same as setting of a fission reaction, now is it? --Jayron32 04:48, 13 December 2010 (UTC)[reply]
I hope not. Ginger Conspiracy (talk) 04:56, 13 December 2010 (UTC)[reply]

@Jayron: 1) I know they don't usually impact matter, but sometimes they do, hence neutrino detectors. So it's not entirely out of the realm of possibility that one neutrino (or possibly more, right before a supernova becomes visible) could hit the nuclear material and cause a decay of some sort.

2) No no no, I don't want to throw out everything (besides cogito ergo sum... unless cogito is an illusion... but I don't think it can be... ugh). Honestly, my knowledge of quantum physics is very limited: in high school and college physics, we had just about everything proven to us through in-depth experiments and history lessons. But I never learned this field, and frankly the online literature sucks... I still only have a basic understanding. My point: if there is good reason to doubt a theory, you do: Earth wasn't caused by a giant turtle's ejaculations because giant turtle's don't seem to exist, and because physics shows it has another history. Do you have reason to doubt that neutrinos cause this? Upon further inspection, it seems our own article confirms the possibility: Neutrino#Neutrinos might affect nuclear decay rate. Of course, all of this is very testable: constantly and closely observe the decay rate of a substance, and eventually a supernova will occur! Magog the Ogre (talk) 11:29, 13 December 2010 (UTC)[reply]

One neutrino can carry as much energy as a fast-served tennis ball (as kinetic energy), but most carry much less. There's no theoretical upper limit on the kinetic energy. I know zilch about how actual neutrino detectors interact with high-energy neutrinos, but maybe someone else can answer that. Neutrinos can interact with nuclei leading to a decay, but nuclei in a fission reactor are decaying all the time anyway, at random, and an occasional extra decay from a neutrino is well below the noise floor. Fusion isn't a self-sustaining chain reaction.
The reason to doubt a novel explanation for radioactivity is that we already have a perfectly good explanation of radioactivity. You seem to be under the impression that radioactivity appears to "break physical laws". It doesn't violate the laws of nature, by definition, and it doesn't violate the Standard Model of particle physics; rather, it's predicted by it. People sometimes talk about particles tunneling through a "classically forbidden region", but this just means that the prediction of that classical theory is wrong. We have a better theory now. Weak evidence of beyond-Standard-Model physics shows up all the time, and in almost all cases the effect disappears in more careful measurements. About 1 in every 20 studies will find an apparent effect at the 95% confidence level even if there's nothing there at all. This neutrino-catalyzed decay effect could be real, but right now there's no particular reason to think it is. -- BenRG (talk) 14:06, 13 December 2010 (UTC)[reply]
Neutrinos may cause deuterium to undergo beta decay, causing fission into two hydrogen atoms. This is the theory behind the Sudbury Neutrino Observatory. ~AH1(TCU) 03:39, 18 December 2010 (UTC)[reply]

Power cable doesn't heat up with surge protector, why?

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I have a plug in heater that I use sometimes. If I plug it strait into the electricity outlet, the cable heats up and starts melting after about an hour of continuous use. When I plug in a surge protector, then the heater into the surge protector, the cable does not heat up or melt at all and it works perfect. I don't understand why. —Preceding unsigned comment added by 76.169.33.234 (talk) 04:00, 13 December 2010 (UTC)[reply]

Whatever it is doing, a heater should not behave like that, it's either broken, or just plain dangerous, I would cut the cord and throw it out. Most appliances are not designed for home maintenance. Your house could burn down and people could die. It's definitely not worth attempting to monkey wrench a solution to problems involving appliances plugged into the grid. As to what the surge protector is doing, my guess is current limiting, however this is not what the surge protector is really designed to do, it might be a byproduct of its function, so it's not a solution to your broken heater. Vespine (talk) 04:44, 13 December 2010 (UTC)[reply]

It could be an electromagnetic induction electrical resonance problem. I agree you should discontinue use of the heater at least until you are certain you have repaired its circuit. This is not medical advice, but it might as well be. Contact a professional electrician skilled in alternating current circuit design and repair for the best way to resolve this issue. If you are in the U.S. and you need a referral, try the International Brotherhood of Electrical Workers. Ginger Conspiracy (talk) 04:54, 13 December 2010 (UTC) [Edit: Just call an appliance repair shop for this. Ginger Conspiracy (talk) 09:03, 14 December 2010 (UTC)][reply]

Does the cable heat up or does the plug heat up? It could be the plug is making a bad connection in the wall, but happens to make a good connection in the surge protector (maybe it has tighter contacts or something), then the plug from the surge protector is larger and makes a good connection in the wall (or maybe it's just bigger so can handle the heat better). Ariel. (talk) 05:26, 13 December 2010 (UTC)[reply]
Yes, and in this case it would be the arcing between the contacts in the first case which is making heat. You might hear this, and, if you turn the lights out at night, you might also see some light coming from there. If this is the problem, or even if it's not, this melting wire does sound quite dangerous. StuRat (talk) 06:15, 13 December 2010 (UTC)[reply]
The best advice is if the any part of the device is heating up to the point of actually melting, throw the whole thing away. Replacing the device is cheaper than replacing your house. --Jayron32 06:17, 13 December 2010 (UTC)[reply]
...but the house may be rented! ;-) --Stephan Schulz (talk) 09:53, 13 December 2010 (UTC) [reply]
And even if you own your house, if you have it over-insured, you are making some sweet $$$. Googlemeister (talk) 14:56, 13 December 2010 (UTC)[reply]
It is obvious that many of the people answering here do not have a clue. A surge protector is not current limiting to normal load and it is very unlikely that electromagnetic induction electrical resonance has any thing to do with this. Obviously you should not use the heater as long as this is unresolved. The advice to throw out the heater can be dangerous. As suggested earlier if it is the plug or the cord close to it that gets hot it is probably a problem with the outlet and if you throw out the heater and by a new the risk is that the same will happen and possible start a fire. Make sure you know were the fault is, if it is in the outlet you should probably call a electrician, if it is in the heater or cord and you are sure you know how to do it repair it otherwise it is probably cheapest to throw it away and by a new. Even if it is a faulty outlet you should not use the cord since it is heat damaged. To me it seams that the most probable cause are bad contact (Not necessarily arcing.) between the plug and the outlet.--Gr8xoz (talk) 11:20, 13 December 2010 (UTC)[reply]
The OP's IP indicates they are in the US where the supply voltage is about 120 VAC. The heater power rating should be known. If it is P watts then the supply cable and associated connectors must carry a current I = P / 120. Example: a 1 kW heater draws 8-1/3 amps. The cable must be of sufficient gauge, and its connectors in proper condition, such that there is imperceptible warming during continuous use. Clearly that is not the case here. I can't explain the effect of the surge protector, but a new thicker cable is called for. The cable should not be kept coiled in use. Cuddlyable3 (talk) 13:22, 13 December 2010 (UTC)[reply]
Is there any other possible explanation for cord heating without a surge protector other than induction resonance? The element may be faulty. Ginger Conspiracy (talk) 09:01, 14 December 2010 (UTC)[reply]
Is the exposed metal of the plug blades corroded, dirty or oxidized? Is the outlet an old one? That could cause the plug in the outlet to heat up. Maybe the surge protector has a lower resistance plug itself, and has tighter and lower resistance contacts in its socket. I would get the outlet checked or replaced, and would not use the heater. (But my house is not overinsured). Edison (talk) 02:00, 14 December 2010 (UTC)[reply]

Use a volt/ohm meter to measure the resistance across the pins of the wall plug and then call an appliance repair shop about it. The element may have lost resistance. It should be about 10 ohms. If there is a resonance problem the resistance should be much less. Ginger Conspiracy (talk) 09:01, 14 December 2010 (UTC)[reply]

I do not understand how resonance would occur when a low resistance, like a heater is connected to the mains. Resistance makes for a low Q circuit and dampens resonance, in general. Would someone please explain? I am familiar with resonance problems (ferroresonance) when certain transformer connections are made in utilities, but there there is a large capacitive and inductive reactance rather than the relatively small resistance of an electric heater. Edison (talk) 16:30, 14 December 2010 (UTC)[reply]
I was thinking maybe some part of the heating element could be changing resistance in response to heating or electromagnetic feedback which may be present in coiled elements. A variety of feedback situations could occur, beating with other parts of the circuit's modes. However, at this point I'm convinced it must be a bad (partial) connection between the particular plug and the particular socket, which seems a lot more likely. Try bending the plug prongs out slightly and see if it still happens. Ginger Conspiracy (talk) 11:24, 15 December 2010 (UTC)[reply]
Ginger Conspiracy, the OP reports the cable heating, not a connector. There is no evidence to convince you of the opposite. Your unlikely ideas about resonances are unhelpful as long as they are speculations about a heater that we know nothing about. Advising the OP to try bending plug prongs or to use a VOM instrument is DIY guidance that the Ref. Desk should not risk giving. Cuddlyable3 (talk) 00:30, 18 December 2010 (UTC)[reply]

Two scientific/medical review articles

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Please move this if it is in the wrong place. I am looking for two peer-reviewed, published articles that review a medical condition. It can be any condition, but ideally a neurological one. Said review articles would be reviewing previously published primary sources and itself would be considered a secondary source. Thank you. Basket of Puppies 04:14, 13 December 2010 (UTC) [reply]

Extended content
I would start by trying google scholar or pubmed. Vespine (talk) 04:36, 13 December 2010 (UTC)[reply]
I was hoping to be suggested to specific articles. Basket of Puppies 04:39, 13 December 2010 (UTC)[reply]
Well, there's two things that can happen now: someone can look up some neurological condition on google scholar and pick two articles for you, or you can look up some neurological condition on google scholar and pick two articles for yourself. HINT: If you give it a go and get stuck on a particular point, then ask for assistance, you're much more likely to get help then if you just ask people to do the leg work for you. Vespine (talk)
I appreciated everything but the sarcasm. Unnecessary. Please close this thread. Basket of Puppies 05:14, 13 December 2010 (UTC)[reply]
You're welcome, if you don't want sarcastic replies, don't make condescending demands ;) Vespine (talk) 05:44, 13 December 2010 (UTC)[reply]
WP:CIVIL. And none of my requests were condescending. At all. Basket of Puppies 05:54, 13 December 2010 (UTC)[reply]
It takes only seconds for people familiar with medical research to answer this. Here are two for mesial temporal lobe epilepsy: PMID 20976764 and PMID 18359666. Looie496 (talk) 06:51, 13 December 2010 (UTC)[reply]

Problem with ChemSketch

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I have a problem with ChemSketch: How do you make the brackets and charge (something like: [S=C=N]-) around an ion (in ChemSketch) with the charge outside of the brackets, but not on the atom(s)/molecule(s)? YOSF0113 (talk - contributions) 06:38, 13 December 2010 (UTC)[reply]

It's been a while since I have used it (I use MARVIN now more often), but I am pretty sure that ChemSketch requires one to indicate formal charge on lewis structures. That is, one of those atoms in your isothiocyanate ion (in your structure, it is the N) has a 1- formal charge, and I think ChemSketch requires your lewis structure to indicate as such. --Jayron32 06:54, 13 December 2010 (UTC)[reply]

I meant that I wanted to do this: [S=C=N]- instead of S=C=N- or [S=C=N-]. YOSF0113 (talk - contributions) 07:08, 13 December 2010 (UTC)[reply]

The answer is "I don't think you can". I think you need to indicate proper formal change, which requires you to assign the 1- charge to one of the atoms in the ion. The correct atom, from your structure, is the N. The 1- charge is not delocalized in this case; it is actually on the N. (this is a shortcoming of lewis structures in general, their inability to accurately represent charge distribution, especially fractional charge distribution, in a single structure, but I digress, and that isn't really relevent to this discussion). --Jayron32 07:16, 13 December 2010 (UTC)[reply]
Seems like you should be able to do it with manually-positioned arbitrary text elements? ChemSketch wouldn't recognize it as the chemical meaning you want, but it would look the way you want. DMacks (talk) 07:32, 13 December 2010 (UTC)[reply]

What I meant is something like these (don't take the SCN seriously, it was just an example): . YOSF0113 (talk - contributions) 08:06, 13 December 2010 (UTC)[reply]

Opening a .mol file in Accelrys Discovery Studio Visualizer

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I have problems with opening a .mol file in Accelrys Discovery Studio Visualizer 2.5.5. When I open the file through DSV, I can see the data but I cannot see the 3D model in the Visualizer. Can anybody help me? YOSF0113 (talk - contributions) 12:01, 13 December 2010 (UTC)[reply]

Please ask at https://community.accelrys.com/index.jspa instead. Ginger Conspiracy (talk) 09:04, 14 December 2010 (UTC)[reply]

Appropriate way to describe the breaking of the neck

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If an experimental animal was sacrificed by breaking its neck, what is the appropriate way to desribe it? Cervical fracture? --129.215.47.59 (talk) 14:09, 13 December 2010 (UTC)[reply]

Oh, wait, how about: cervical dislocation? --129.215.47.59 (talk) 14:14, 13 December 2010 (UTC)[reply]
Yes, Wikipedia has an article on cervical dislocation (and the correct meaning of sacrifice).--Shantavira|feed me 15:16, 13 December 2010 (UTC)[reply]
Eh? Sacrifice is used correctly in this context, Shantavira. It is widely used this way in scientific literature. TenOfAllTrades(talk) 15:43, 13 December 2010 (UTC)[reply]
According to this paper, "The term 'sacrifice' is used by experimental biologists to describe methods for killing laboratory specimens." The paper is titled "Sacrifice and the Transformation of the Animal Body into a Scientific Object: Laboratory Culture and Ritual Practice in the Neurosciences" which suggests both meanings are considered. ;) WikiDao(talk) 18:45, 13 December 2010 (UTC)[reply]

Taste

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We have a good traditional vocabulary for most senses:

  • sight (we can describe what we see to others with considerable precision)
  • sound (we have fairly precise vocabulary for different audible sensations)
  • touch (we have many words for how things feel and can communicate what things feel like to others)

While these are subjective we have a good shared vocabulary that allows novel sensations in these senses to be described by use of well understood abstractions.

I'm not aware of a vocabulary that treats taste with similar precision. Is there one? If not, why not? FT2 (Talk | email) 18:20, 13 December 2010 (UTC)[reply]

What immediately springs to mind is Wine tasting descriptors. It is not that precise though, I regularly need several glasses/bottles etc.. And of course, there is the Meilgaard Beer Flavour Wheel. Much better, but I still need several pints to get my description right; at least -that is my excuse. --Aspro (talk) 18:28, 13 December 2010 (UTC)[reply]
Excuse me for being pedantic, but it is important to distinguish between taste and flavor. We have an excellent vocabulary for describing taste: all it can be is sweet, salty, sour, bitter, and perhaps umami. Flavor, though, is a combination of taste and odor as well as other qualities such as astringency and heat. The difficulty comes from odor: our understanding of the perceptual structure of odor space is extremely poor. It seems to be very high-dimensional. Looie496 (talk) 18:40, 13 December 2010 (UTC)[reply]
That's what I mean. Why is it so poor, given that a wide range of good quality descriptors have emerged during the millennia of human history for almost every other facet of human existence (including apparently all other sensory spaces, most experiences, and most subjective and emotional spaces)? Why not odor/taste which have been around since the dawn of human history? And what descriptors do exist? FT2 (Talk | email) 20:33, 13 December 2010 (UTC)[reply]
You missed what he said about "high-dimensional". What he means is that color is 3 dimensional - all colors can be described in terms of red, green, blue (i.e. varying amounts of each in combination). Sound can be described in 1 dimensions - just frequency (maybe two if you want to include volume, and just possibly 3 if you want to describe if the frequency rises or falls). Touch is also 3 dimensional - position and height. But flavor is higher dimensional - you can not describe each flavor in terms of 3 base flavor components, instead there seem to be many of them (hundreds? thousands?) Because of this there is no clear vocabulary you can establish, at best you need to start naming each one of the possibilities. Ariel. (talk) 21:17, 13 December 2010 (UTC)[reply]
I don't think at the level we experience it that's true. Sound may be a waveform, but we don't experience or communicate a waveform, we communicate the experience of it. The waveform of a symphony may be a line-graph; the audio experience of it (and the sounds in it) are not. If one tried to create a "common basis of sounds" (hundreds? thousands?) the exact issue comes up as you correctly state, yet we have historically acquired a vocabulary to communicate sounds and their combinations to a higher level than taste/odor. That's what I'm curious about. FT2 (Talk | email) 23:58, 13 December 2010 (UTC)[reply]
It's precisely the low-dimensionality of sound that allows up to create such a vocabulary. Think of music terms, there are words for tempo, various pitches, key etc. All those boil down to the basic dimensions of sound - they combine in complex ways of course, but their core is simple. What words describe a sound that do not boil down to the basic dimensionality? (Words like harsh and sweet don't count since those describe emotions, not sound, and they can, and are, applied to all the senses.) Ariel. (talk) 00:19, 14 December 2010 (UTC)[reply]
I would quibble with the claim that sound is low-dimensional. If you have a periodic wave, such as a spoken vowel, a note, or a chord, you can use Fourier analysis to describe the wave in terms of component frequencies, which is essentially what our ear does. In theory, this identifies the sound as a point in an infinite-dimensional Hilbert space! Not all of these dimensions are relevant to human hearing, since we can only hear a finite range of frequencies-- ~20 to 20,000 Hz-- which still gives 1,000 dimensions. There is also a huge range in volume; the loudest tolerable sound is about a trillion times as loud as the softest audible sound. The amazing scope of our hearing is why audiophiles can be so picky about the quality of recorded music and the speakers producing it; consider how many megabytes a song file requires when sampled at the highest quality! For all senses, our brains simplify things considerably before we are even conscious of our sensations (which sometimes leads to optical, or other, illusions), and we simplify them further when we give a simple verbal description. However, we can make these short descriptions incredibly useful, for just about any sensation, when we have enough points of reference in common and we train ourselves to observe carefully. I think 86's account above is fascinating, showing a focus on taste and flavor that most of us never cultivate.140.114.81.98 (talk) 02:49, 14 December 2010 (UTC)[reply]
A Fourier transform is only if you want to analyze the entire wave - including the time component. But time is implied, and once you have that you need only a single dimension (amplitude) to fully describe the wave (obviously you need many sequential amplitude measurements, but that doesn't change the dimensionality). In contrast color needs 3 (and similarly if you want a picture you need to include two additional dimensions: x,y). The volume range makes no difference, it's still a single dimension. Ariel. (talk) 05:32, 14 December 2010 (UTC)[reply]
Saying that "The only tastes are sweet, salty, sour, bitter, and perhaps umami" is like saying "The only colors are red, blue, and green". That's true individually, but the combinations keep Crayola in business. 72.10.110.109 (talk) 23:06, 13 December 2010 (UTC)[reply]
I've been involved in commercial taste-testing (really flavour and taste), and it's very important for these things that everyone is using the same points of reference. As such, there are standard words to describe set classes of flavours, fairly specific to the things being tasted. Beginning tasters are given sheets with commonly used references for the important flavours, labelled with the preferred term in that organisation: they taste a few standard examples and learn the standard way to describe them. Obviously this is for qualitative assessment: more quantitatively, you can simply decide which of three samples are the same. Or you can make qualitative assessment more quantitative, rating different samples according to where they lie on a scale between two standard flavours or tastes. Really, people are quite good at describing references for flavour, but it can easily be standardised when needed, which also helps people concentrate on the flavours the organisation considers important. 86.161.208.185 (talk) 19:16, 13 December 2010 (UTC)[reply]
Is there an article, field name, or website on this? FT2 (Talk | email) 23:59, 13 December 2010 (UTC)[reply]
I'm afraid the stuff I did was all tied up in commercial secrecy, with everything using commercially specific terms, so I don't know how it ties into wider study. However, when you look at amateur or public tasting, like with chocolate or wine, you can see the same things happen. For example, "The Chocolate Companion" by Chantal Coady discusses the way professional tasters talk about different "notes" or characteristics, and compare with fruits, flower blossoms, balsam, etc. It's not the best source (I'm sure there are more detailed treatments out there), but it's a publically published source that fits my experience. For example, American chocolate like Hershey's has a flavour commonly described as 'cheesy' or 'barnyardy': if you'd never heard this before, it wouldn't be obvious that these describe the same flavour, but when people are told this (having eaten Hershey's), they're usually clear on what flavour is being described, and can confidently use it to describe things with a similar flavour. A particular group of tasters would agree whether to use 'cheesy' or 'barnyardy' for that flavour, for clarity. Similarly, there are agreed references for mouthfeel, although anyone can use a commonly experienced reference and expect to be understood. I've had to be careful, and have used this particular book I had to hand so that I'm sure I only used public information here. 86.161.208.185 (talk) 00:23, 14 December 2010 (UTC)[reply]

Meridiungulata out of Xenarthra?

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On the German page (de:Südamerikanische Huftiere), anyway a bad title, they claim, naturally unsourced, that Meridiungulata evolved from Xenarthra! How can an order which doesn't include much more than anteaters, armadillos and sloths evolve into hoofed mammals? Even if it can, has somebody seriously thought about it? Otherwise i will be bold! --Eu-151 (talk) 20:02, 13 December 2010 (UTC)[reply]

On the Wikipedia page Ungulates indicates such a relationship as well, though it too is uncited. I myself am not a taxonomist, so I will leave it to others to comment on such an idea's veracity. --Jayron32 20:08, 13 December 2010 (UTC)[reply]

A relationship is okay, but Meridiungulata (which ended up with a rhino-like Toxodon having Xenarthra as ancestors, as implied in the German article? --Eu-151 (talk) 21:11, 13 December 2010 (UTC)[reply]

This is very tricky stuff, but our article Atlantogenata contains some possibly relevant information. Looie496 (talk) 23:22, 13 December 2010 (UTC)[reply]

Atlantogenata also only suggests that Xenarthra and Meridiungulates are sister groups — Preceding unsigned comment added by Eu-151 (talkcontribs) 19:13, 14 December 2010 (UTC)[reply]

Interfamiliar hybrid

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There are interspecific mammal hybrids (see Panthera hybrid), intergeneric hybrids are already claimed to be rare (see Geep), but now on the Roe Deer page i find an, even sourced, claim that C. capreolus can interbreed with Ovis aries aries. Do we know any other hybrids crossing families (Roe Deer are cervids, sheep are bovids)? If yes, which families, genus an d species can interbreed? If no, can someone check the source and say whether this is a sensation or not? — Preceding unsigned comment added by Eu-151 (talkcontribs) 20:06, 13 December 2010 (UTC)[reply]

I found that book on google books, it just appears to be a list of some sort (less than 100 pages), and although this looks to be a google error its under the "juvenile nonfiction" category. Is there anything more modern that makes this claim? 173.183.68.27 (talk) 05:12, 14 December 2010 (UTC)[reply]

Thallium production

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Is it true that only 10 metric tons of thallium are made each year? It sounds too small. This is found in the fourth paragraph of "Occurrence and Preparation" in the article thallium. Thanks, --Chemicalinterest (talk) 23:41, 13 December 2010 (UTC)[reply]

No that seems reasonable: I'm actually surprised it's as high as that! The cite is to the U.S. Geological Survey, which inspires confidence. Thallium has very few uses, and those uses don't involve huge quantities of the metal. Physchim62 (talk) 23:53, 13 December 2010 (UTC)[reply]
To give a comparison, the world production of rhenium was 52 metric tonnes, and rhenium is non-toxic with wider uses. Physchim62 (talk) 00:10, 14 December 2010 (UTC)[reply]
I don't typically think of thallium as a "precious metal" as I am not a murderer. No wonder there is only one picture of a thallium compound in the whole wiki. BTW, I left some comments on talk:thallium. --Chemicalinterest (talk) 00:11, 14 December 2010 (UTC)[reply]