Wikipedia:Reference desk/Archives/Science/2013 September 17

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September 17

Cattle teeth and bones

After they kill a cattle for its meat and skin, do they use the teeth and bones for anything, or are they just discarded? ScienceApe (talk) 00:00, 17 September 2013 (UTC)

See bone meal. --Jayron32 00:08, 17 September 2013 (UTC)

Marrow and cartilage are used for gelatin and broth. μηδείς (talk) 00:52, 17 September 2013 (UTC)

A bit old fashioned, but animal glue is favoured by traditional joiners and carpenters. Alansplodge (talk) 18:39, 18 September 2013 (UTC)

What study is being cited?

In this from the Daily Mail, it is said "one study in which a group of patients were given a saline solution which they were told could be chemotherapy. Despite the fact it was only salt water, 30 per cent of the patients lost their hair". Does anyone know what study the book Mind Over Medicine is citing? Thanks. Biosthmors (talk) pls notify me (i.e. {{U}}) while signing a reply, thx 07:56, 17 September 2013 (UTC)

@ Biosthmors (talk · contribs) This "fact" seems to be bandied about casually all over the place without a source, but I found a mention on this page that looks like it's citing the same study. If so, it's Fielding, J.W.L. "An Interim Report of a Prospective, Randomized, Controlled Study of Adjuvant Chemotherapy in Operable Gatric Cancer: British Stomach Cancer Group." World Journal of Surgery 7 (1983): 390-99. I don't have access to check whether it's the right one or not. - Karenjc 11:46, 17 September 2013 (UTC)

Looking at the full text, the reported incidences of "alopecia" were 74% and 49% in the two drug treatment arms of the study, and 30% in the placebo arm. Severity isn't discussed—we don't know how much hair loss occurred. (Alopecia can refer to partial or total hair loss.) Further, all patients – in both drug arms and in the control arm – had major, recent surgery to remove gastric tumors. In the words of the study authors,

"Analysis of the toxicity associated with chemotherapy, though confirming its more frequent occurrence in the treated patients, also demonstrates that there are significant "toxic" effects in the control group which must be attributable to either the placebo effect, the underlying malignancy, or the operative procedure."

While the paper didn't explicitly address this point, it's also worth noting that about two-thirds of the patients were over age 60, and about two-thirds of the patients were male: populations expected to see naturally-occurring hair loss even under normal conditions. In other words, it is an open question how much of the hair loss could be attributed to genuine 'placebo effect', versus the physiological and psychological stresses of serious cancer and major surgery, or the natural properties of a mostly-male, mostly-older patient population. Baldly declaring that all of the hair loss in the placebo group was due to the placebo effect (and sweeping all the other contributing factors under the rug) is an interpretation that isn't justified by the paper's actual data or conclusions.

To actually measure the potency of the placebo effect here, the study would have needed a fourth arm, in which the patients did not receive any injections. (Or, even better, where the patients receiving saline were told explicitly that it was just inert saline not expected to have any effect whatsoever.) Good luck getting ethics committee approval for that one, though. TenOfAllTrades(talk) 14:42, 17 September 2013 (UTC)

Note that modern chemotherapay is different for different types of cancer. Chemo for breast cancer always causes near total or total hair loss - head hair, eyebrows, pubic hair, total loss. Currently favoured chemo for colon cancer normally does not cause much hair loss, though it makes you feel very sick. Not sure about chemo for gastric cancer. Note also, that some patient literally worry themnselves sick when given a diagnosis of cancer. Extreme mental stress and worry can cause some hair loss. There's more: Elderly females are accustomed to going to the hirdressor for frequent "hairdos" which may include styling and treatment to make their thinning hair look more healthy and full. When they get their diagnosis of cancer, they can then think, well I won't waste any more money on the hairdressor as it will all fall out anyway. That's when the poor husband discovers his still bueautiful 70 year old wife fluffy curly brown or blond hair is in reality a wrinkly old lady with thin grey hair. There's still more: Many cancers (breat, womb, prostate, etc) are hormone dependent. If a women with a female cancer is given treatment such as tamoxifen, they will loose some head hair and gain some facial hair. Hormone therapy is not usually given until chemo is finished though. A man with prostate cancer given hormone treatment will loose facial hair and gain head hair (and maybe some breast growth). All this means any such study that may be the source of the OP's question is fraught with difficulty and is unlikey to be of value unless these issues are managed. 1.122.41.205 (talk) 00:23, 18 September 2013 (UTC)

Liberty + mental health

Why do people exist who strongly oppose personal liberty? For instance, there are people out there who strongly believe we should legally limit the personal freedoms of transexuals to choose their own name. Do such people have brain pattern differences? Any research on this? Pass a Method talk 08:39, 17 September 2013 (UTC)

The difference is often a cleaner brain caused by irrational adoration of a leader. HiLo48 (talk) 09:59, 17 September 2013 (UTC)

What about the legal limits on heterosexuals to choose their own name? They are the exact same limits. 1.122.41.205 (talk) 11:08, 17 September 2013 (UTC)

But why don't these groups oppose name changes by heteros? Why only oppose name changes by trans people? Double standards. Pass a Method talk 12:15, 17 September 2013 (UTC)

Convicted criminals don't necessarily get to do as they please. ←Baseball Bugs ^{What's up, Doc?} carrots→ 12:33, 17 September 2013 (UTC)

I don't see any connection between transgender individuals and convicted criminals. An unusual parallel to draw. Liz ^{Read! Talk!} 12:55, 17 September 2013 (UTC)

It is reasonable to assume that the OP's question was prompted by the Bradley Manning vs. Chelsea Manning Wikipedia article title change debate, and while the OP phrased the question more generally, BB is certainly referring to that specific case, and not to transgender people in general. -- ToE 13:53, 17 September 2013 (UTC)

Yes, that was my assumption. By contrast, I don't recall there was any significant outcry over Chastity Bono becoming Chaz Bono. The bigots are going to hate it no matter who it is. But as a legal matter, I don't think there's anything stopping someone like Chastity/Chaz Bono from getting a name change. The Manning case has to do at least in part with a lawyer negotiating for a different prison from Leavenworth. Hence the cynicism about that situation. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:20, 17 September 2013 (UTC)

Your assumption was not at all self-evident, as Manning is hardly the only transsexual to request a name change. The very fact that it's possible to get better treatment by being a woman is a clear case of sexism, yet it apparently doesn't upset you as someone (supposedly) trying to get better treatment for himself/herself. -128.112.25.104 (talk) 17:58, 17 September 2013 (UTC)

Manning's the one in the news recently, though. I'd like to see some specific cases to support your theory. ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:44, 17 September 2013 (UTC)

(128.112 here) It is not my theory; it was yours. Why would Manning want to negotiate for a different prison, except to get better treatment at that prison? If he claimed to be a woman to get transferred, does it not imply that she expects to be treated better as a woman than as a man? I was curious about what support you had for your theory. --140.180.242.75 (talk) 23:07, 17 September 2013 (UTC)

To get better treatment because it wouldn't be Leavenworth. And not my theory, but the theory of a lawyer who commented to the Washington Post. ←Baseball Bugs ^{What's up, Doc?} carrots→ 00:10, 18 September 2013 (UTC)

Just a side note on wording - hetero isn't really the opposite of trans, as it describes sexual orientation rather than gender. A trans person can be heterosexual. Cissexual is often used within the community to mean someone who isn't trans or genderqueer in any way, but I haven't seen it used much outside of circles that discuss trans issues in a positive light and I wouldn't expect the average person to know what it means. Usually I use "not trans" in general conversation when I need an opposite. Don't worry - I don't think you're being offensive, you're clearly supportive of trans people so I figured you would like to know that the language you were using wasn't quite accurate. Katie R (talk) 13:45, 17 September 2013 (UTC)

I think the word you're looking for is Bigotry. 196.214.78.114 (talk) 12:59, 17 September 2013 (UTC)

Do you, the OP, oppose the liberty of serial killers to continue killing people? If so, why do you want to legally limit the personal freedoms of serial killers by putting them in jail?

My guess is that you'll argue that although personal freedom is good, murder is highly immoral and detrimental to society, so restricting a murderer's freedom is better than letting him go free. The same logic applies if you see transsexualism as immoral and detrimental to the sanctity of the family. It doesn't matter if this opinion is correct--if it is correct, it follows that restricting a transsexual's freedom for the greater good might be justified in the same way that restricting a murderer's freedom is justified. --Bowlhover (talk) 13:12, 17 September 2013 (UTC)

But the concept of "sanctity of the family" should be formally defined. If you were to attempt to give a formal definition of this, you would probably end up having to argue in a circular way. Count Iblis (talk) 13:17, 17 September 2013 (UTC)

The Bible explicitly prohibits both homosexuality and transsexualism. I'm sure you know as well as I do which passages prohibit the former. For the latter: "The woman shall not wear that which pertaineth unto a man, neither shall a man put on a woman's garment; for all that do so are abomination unto the Lord thy God" (Deuteronomy 22:5).

If you define a "sacrosanct" individual/family as one that does not explicitly violate God's law, as (supposedly) revealed in the Bible, transsexualism is definitely out. Deuteronomy is the same book containing the Ten Commandments (well, Exodus does too), one of which is "thou shalt not kill", so my analogy with serial killers is appropriate: if a Christian believes that his morality comes from the Bible, it makes perfect sense to put transsexualism/homosexuality in the same category as murder, as both violate God's law and are therefore immoral. --Bowlhover (talk) 14:01, 17 September 2013 (UTC)

Of course, by the same logic, eating bacon is also equivalent to murder since "The pig is also unclean ... You are not to eat their meat or touch their carcasses" (Deuteronomy 14:8). Gandalf61 (talk) 14:31, 17 September 2013 (UTC)

The Bible does not explicitly prohibit homosexuality, that is an artifact of incorrect translation from the original Greek. The carnal acts associated with it is meant to be prohibited. Plasmic Physics (talk) 22:18, 17 September 2013 (UTC)

Prohibiting someone's orientation, by itself, would be like prohibiting having six fingers instead of five. ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:28, 18 September 2013 (UTC)

Because it would be too confusing if we changed half the article titles of List of people claimed to be Jesus to Jesus Christ? People can choose their names. They can't choose our article titles. We choose our article titles in order to make the best encyclopedia. That's often the same as the person's name, but not always. --GRuban (talk) 14:23, 17 September 2013 (UTC)

A reminder to all that this is a reference desk, not a forum for opinions or debate. Our articles on authoritarianism and conformity contain sections on psychological studies about these ideas and behaviors. I also recall reports of a study that found differences between "brain patterns" in U.S. conservatives and liberals. (Conclusions about "liberty" within these ideologies are your own to make.) Try googling those keywords (my workplace internet access is limited). 198.190.231.15 (talk) 14:34, 17 September 2013 (UTC)

(ec) Back to the OP's question - there's probably an f-MRI study on it. It seems like there is one on everything, not that it will prove anything - there is a lot of controversy on the usefulness of f-MRI studies on these sorts of subjects. I skimmed [1], and although it focuses on race it looks like it could be interesting to you. Katie R (talk) 14:38, 17 September 2013 (UTC)

"there are people out there who strongly believe we should legally limit the personal freedoms of transexuals to choose their own name." Where is the evidence here? There are bigots of all stripes, but I'm not sure what the point of the question is. Also this doesn't seem like a reference desk post, it seems like a personal forum debate about naming of trans* people. --Obi-Wan Kenobi (talk) 15:56, 17 September 2013 (UTC)

I read the question as asking if there has been any scientific research into why bigotry exists. That's why I linked the article on research on subconcious prejudices in race. I cringed when I read the question because I worried it would go down the personal opinion/forum route (especially due to using the current hot topic of trans naming as an example), but I think the question itself is something we can answer and provide references for. If you want to discuss the validity of the question further we should probably move to the talk page. Katie R (talk) 17:10, 17 September 2013 (UTC)

Ok thanks Katie. If you can steer this back to answer the broader topic, eg what are the scientific basis of bigotry for example, then it will be illuminating, and I hope we'll keep other discussion off this thread as it's not ontopic.--Obi-Wan Kenobi (talk) 17:19, 17 September 2013 (UTC)

• Given where this thread has been linked (e.g. Talk:Alexis Reich in a move request and User talk:StAnselm), this comes across as a thinly veiled attack on certain editors. The Reference desk is not a forum or a way to circumvent conventional talk page guidelines against soapboxing. -- tariqabjotu 17:05, 17 September 2013 (UTC)

• What part of not soliciting debate is confusing? Why are questions being directed at Bugs for his opinion? Why are any questions with the pronoun "you" being posted here? μηδείς (talk) 04:44, 18 September 2013 (UTC)

Why are questions being directed at Bugs for his opinion?

Because Bugs offered his unsolicited opinion on a topic only tangentially related to the question, and in a very confusing way. Hence the confusion of many editors.

Why are any questions with the pronoun "you" being posted here?

Because I wanted to illustrate to the OP that he is also in favor of severely restricting other people's liberties when those people act immorally. Therefore, there's nothing surprising, unusual, or uncommon about the group of people that the OP views negatively, as almost everybody is part of that group. --Bowlhover (talk) 03:28, 20 September 2013 (UTC)

Closest relative commonly eaten by humans

Discussing birds eating birds the other day, the question arose "Of the animals commonly eaten by humans, which is the most closely related to us?" For the purposes of this question, let's ignore any primates. Any decent notion of relatedness is OK, be it most recent common ancestor, or number of degrees of separation in a standard taxonomy. Thanks! SemanticMantis (talk) 16:27, 17 September 2013 (UTC)

My best guess is Philippine flying lemur, depending on if it meets your definition of "commonly eaten." The article says their meat is eaten as a delicacy. They're not true lemurs, and aren't primates. Based on Euarchontoglires#Organization I don't think you can get any closer without being a primate. Katie R (talk) 16:51, 17 September 2013 (UTC)

Interesting, thanks! That does seem to be an overall winner, if not "common." SemanticMantis (talk) 18:22, 17 September 2013 (UTC)

Why exclude primates? Dauto (talk) 18:11, 17 September 2013 (UTC)

• Revision: since "common" is indeed vague, how about this revision: Consider "mammals commonly eaten by humans" to include cattle, pig, lamb, deer, goat, rabbit, maybe groundhog and squirrel -- which of these has the most recent common ancestor with humans? Basically, I'm interested in mammals you could find served at a restaurant in the USA (perhaps pricey, perhaps novelty, etc.). SemanticMantis (talk) 18:22, 17 September 2013 (UTC)

If we're excluding primates - then the most recent split would be between Rodents and Primates - so any rodent will do. All rodents are at the same 'distance' from us in the family tree. The rabbit is the most reasonable candidate because I've certainly seen that served in US restaurants - squirrels are also eaten in the US - but not in many restaurants, I suspect. SteveBaker (talk) 18:32, 17 September 2013 (UTC)

Nitpick: Rabbits aren't rodents. They are Lagomorphs. Doesn't change the conclusion, though. --NorwegianBlue ^talk 20:19, 17 September 2013 (UTC)

True - but they come from that same branch as the rodents. The mammalian family tree that I was looking at didn't make the distinction...sorry! SteveBaker (talk) 20:26, 17 September 2013 (UTC)

The full and proper (this week!) set of taxonomy is that the Euarchontoglires split into the Glires and the Euarchonta. The Euarchonta split off into Primatomorpha and that group became the true primates - in which we humans are situated. The Glires split into rodents and lagomorphs...which is where the rabbits are.

So, since we don't much eat tree-shrews or flying lemurs in US restaurants - the Glires are the nearest group - and that leaves you rabbit, hares and pikas in the Lagomorphs and things like mice, rats, squirrels, porcupines, beavers, guinea pigs, and hamsters in the rodents. If you don't think rabbits are eaten commonly enough to count here - then you have to look back further to the split between the Euarchontoglires and the Laurasiatheria - which would mean that whales, dolphins, pigs, deer, antelope, cattle, sheep, goats, horses, wolves, bears, lions and tigers are all equally close.

The bottom-line choice then is rabbits - or if you don't think those are served often enough - then deer, cows, sheep and pigs are all equally likely candidates.

SteveBaker (talk) 20:41, 17 September 2013 (UTC)

Guinea pigs and their relatives are rodents and are commonly eaten in parts of South America. HiLo48 (talk) 21:28, 17 September 2013 (UTC)

• Thanks all! Bonus points: anyone know a reference for most recent common ancestor for humans and rabbits, or humans and guinea pigs? SemanticMantis (talk) 01:44, 18 September 2013 (UTC)

Euarchontoglires explains that the split came somewhere in what is now Europe - about 85 to 90 million years ago - in the cretaceous when large dinosaurs were still around. It would probably have looked something like a long-extinct Eomaia (see picture at right)...but the evidence for the split between primates and glires (rodents and rabbits) is based on DNA evidence - I doubt we have fossils of the actual common ancestor. But it would likely have been a typically shrew-like animal, maybe the size of a rabbit. SteveBaker (talk) 14:42, 18 September 2013 (UTC)

• An alternate theory is that humans descend from chimps and pigs, http://phys.org/news/2013-07-chimp-pig-hybrid-humans.html. There seem to be enough sources on this topic to make an article, eg http://hplusmagazine.com/2013/09/01/between-chimp-pig-and-superman/ but there is no Wikipedia article. Then pork would be the closest. Graeme Bartlett (talk) 12:23, 18 September 2013 (UTC)

Ah! The infamous "MFAP" (Monkey f**ked a pig!) hypothesis rears it's ridiculous head again! So...a wild boar has sex with a female chimp - and the offspring is viable and able to produce more offspring of it's own? Hmmmm...well that's credible! If the offspring of such closely related species as horses, donkeys and zebra - or lions and tigers are infertile - then pigs and chimps have NO chance! This is a classic case of first coming up with a crazy theory, then pulling small bits of evidence from all over the place (while ignoring all contrary evidence) to try to justify it. Bottom line is that there is no way for a 36 chromosome pig to produce cells that would undergo mitosis and meiosis with 48 chromosome chimpanzee cells. There is just no way for the cellular machinery to make that happen. Not to mention that after 90 million years of divergent evolution, the pig sperm wouldn't even be able to recognize the chimpanzee egg as an egg.

Hell no! SteveBaker (talk) 15:18, 18 September 2013 (UTC)

There is a sense in which this is possible :) The idea doesn't specify when this mating took place. There was clearly some point in time when pigs and monkeys branched away from one another. During this initial parting of ways of the proto-monkey and the proto-pig, there was inevitably some point at which the two populations were largely separate but some interbreeding took place. So at some point in history, MFAP, and we are all shaped by this evolutionary event. :) However, of course, here we're speaking of ancestors, before chimps or pigs as the species we know them now existed. The dismissal of the idea is that there is no gene where humans come up clustered beside Sus scrofa in the BLAST results, with chimps and baboons and such being far, far away. Any such horizontal gene transfer would be exciting and the topic of much research, though we'd expect the sexual agent to be a virus of some sort rather than a coupling! Wnt (talk) 15:46, 18 September 2013 (UTC)

No, because what you're missing is that at the time that the Euarchontoglires (rodents/primates/rabbits) and the Laurasiatheria (pigs,goats,cows,whales,dogs,cats) split, the proto-pig was NOTHING like a modern pig - and the proto-chimp was nothing like a chimp. The so-called evidence for the MFAP hypothesis requires that something very much like a modern pig mates with something very much like a modern chimpanzee. While the Euarchontoglires and Laurasiatheria were still close enough to interbreed - they would have had none of those key genetics that would make them look monkey-like and pig-like. Furthermore, the offspring at that point would simply have produced a line of new animals at the same taxonomic level as Euarchontoglires and Laurasiatheria - and if humans were on that branch, we'd expect to see a dramatically different line of descent for us - with all sorts of similar animals that would be totally unrelated to primates in our history. Humans are undoubtedly primates - but your hypothesis has us belonging to some entirely different line of descent. There is no evidence for any of that. Even the crazy MFAP hypothesis has us descended from other primates. SteveBaker (talk) 12:33, 19 September 2013 (UTC)

Even so, I think it would still be interesting to see how far researchers could get with a program of selecting for "hybridizable" organisms. There are many genetic incompatibilities that block hybridization, but presumably you can select against them like any other trait. At some point, can you make a genome so flexible that it can figure out how to hybridize with many vastly different organisms and shepherd the resulting offspring through meiosis, correct for vastly different developmental scales and time scales, and thereby be ready to ferry genes back and forth between humans and pigs, etc.? Well, it's far fetched - you'd think if it were possible something would have done it - and yet, with biology, you can never really say "impossible". Wnt (talk) 15:50, 18 September 2013 (UTC)

most recent living human relative

Oh, please, a pig? Everyone knows humans are actually most closely related to the Mexican Mole Lizard, right. Here is a link to a paper on the subject at Scientific American. μηδείς (talk) 16:38, 18 September 2013 (UTC)

Surprised no one has yet mentioned bushmeat. Apparently "about 1% of the bushmeat trade is in ape meat", though that is in need of a reference. Astronaut (talk) 17:00, 18 September 2013 (UTC)

The OP specified ignoring primates. μηδείς (talk) 17:03, 18 September 2013 (UTC)

In that case, first prize goes to the guinea pig, it being a commonly-eaten rodent. Whoop whoop pull up ^{Bitching Betty | Averted crashes} 04:40, 21 September 2013 (UTC)

Yes, they are tied with rabbits, (glires), which are also domesticated for meat. See also this recent culinary experiment gone wrong. μηδείς (talk) 05:50, 21 September 2013 (UTC)

Weight gain as a result of overeating

What I'm after are overeating experiments where physically fit people are given significantly more calories to eat than they normally do. What I have found are examples of experiments where the outcome was only a small weight gain in response to a hugely higher calorie intake (e.g. 5000 Kcal per day instead of 2500 Kcal per day). In these experiments the people were typically eating an unhealthy diet, in some of them they were requred to stop exercising.

More interesting would be to see if eating a healthy diet and sticking to a healthy exercise routine would lead to weight gain if the calorie intake is increased on the very long term. In that case, you would probably not be able to increase the calorie intake by a large amount. But something like 4000 Kcal/day should be possible (at least that is what I eat). Count Iblis (talk) 17:25, 17 September 2013 (UTC)

Weight gain happens when you eat more calories than you burn. Different people, with the same body shape and broadly similar work/exercise require different numbers of calories. People's metabolic rates change over time though. Getting into a habit of eating 4000 calories/day will probably result in gradual weight gain if your metabolic rate ever falls. This is why people so often say "I used to be able to eat anything when I was young - but when I hit thirty, my weight just shot up". SteveBaker (talk) 18:24, 17 September 2013 (UTC)

Sword made of Precious metals

I haven't found any information on swords or shields made of god, mainly because all I find is purely videogames, so, why there aren't battle-ready swords made of Gold or silver? 190.60.93.218 (talk) 17:40, 17 September 2013 (UTC)

Seriously? Well, OK. Gold is a very soft metal, and also very heavy (dense). It's like saying, "oh, my tin sword is great, except it just isn't heavy enough". Silver is a little harder and a little lighter, but not likely to be an especially suitable material either. Why would you want to do this? Just to make them more expensive? --Trovatore (talk) 17:45, 17 September 2013 (UTC)

Depleted uranium is used for shields. — Preceding unsigned comment added by Count Iblis (talk • contribs) 17:57, 17 September 2013‎

The count seems to be talking about radiation shields here, not the kind of shield a swordsman carries around. Good thing too, unless it's a really strong swordsman. --Trovatore (talk) 18:02, 17 September 2013 (UTC)

No, DU is sometimes used in modern vehicle armour - basically for the same reason it is used in ammunition. It's fairly hard, fairly cheap, and has a high density, and hence is good for dissipating the energy of modern weapons (where a HE round or kinetic penetrator basically vaporizes the skin of the vehicle). --Stephan Schulz (talk) 18:21, 17 September 2013 (UTC)

Well, OK, still not the sort of "shield" the OP is asking about. --Trovatore (talk) 18:54, 17 September 2013 (UTC)

See also http://xkcd.com/1114/ --Trovatore (talk) 18:05, 17 September 2013 (UTC)

(I should clarify — that has nothing to do with Iblis's DU "shields". DU is not very radioactive. It would be a crappy material for a swordsman's shield, but mainly because it's heavy; the radiation risk I would expect to be vanishingly small.)--Trovatore (talk) 18:09, 17 September 2013 (UTC)

Here's an illustration of how soft gold is. As a child, I remember playing with my mom's wedding ring, which was mostly but not entirely gold. I squeezed on the ring and made it into an oval with minimal effort. This was a gold alloy (so much harder than pure gold), and I was weak even for my age. Still sure you want a gold sword or shield? --128.112.25.104 (talk) 18:07, 17 September 2013 (UTC)

Swords have lots of complicated, and often conflicting needs - strength, flexibility, bend-resistance, chip resistance, lightness (so you can swing it fast), weight (so it has more kinetic energy when it gets there). These are all compromises. Steel is almost universally considered the best material - even in societies where titanium and other more expensive materials have been tried. This site shows a pair of very beautiful titanium swords - but the guys as Blade Forums completely lambasted the thing because of the poor properties of titanium. Gold would produce a sword you could bend in half with one finger! Silver is only slightly harder than gold - it would notch very easily and develop a permanent bend with out too much difficulty.

Generally, if you wanted a fancy ceremonial/decorative sword, you'd make one out of steel and apply thin coatings of more exotic materials to improve the appearance. Here is an "antique" sword with gold plating], for example. SteveBaker (talk) 18:15, 17 September 2013 (UTC)

Oh, I see. I didn't know many of Gold or Silver properties because I've never seen these objects at least large enough for me to know why these materials wouldn't be suitable for swords, thank you. 190.60.93.218 (talk) 19:20, 17 September 2013 (UTC)

The main advantage of gold over most other metals is that it doesn't tarnish, rust, etc. Traditionally, steel swords needed to be oiled to keep them from rusting. So, perhaps a thin gold plating over a steel sword might help protect it from rust, although I suspect this wouldn't work directly on the cutting edge(s), but could help to protect the rest, particularly for a sword often exposed to saltwater (say a pirate's sword). I believe gold on the hilt was often used, especially in ceremonial swords (note that there is some overlap between ceremonial swords and combat swords). Of course, we also have modern solutions to this problem, like stainless steel. And the weight can be an advantage in some cases. While a heavier sword is slower and less maneuverable, it delivers more force to the target, which might help with a muscular sword-wielder attacking an enemy with a shield and/or some form of armor. StuRat (talk) 03:17, 18 September 2013 (UTC)

Wouldn't a halberd be a better weapon for that? 24.23.196.85 (talk) 04:02, 18 September 2013 (UTC)

The question wasn't about halberds, but the choice of materials would likely hold true if it was. --Onorem (talk) 04:16, 18 September 2013 (UTC)

• Didn't the Druids harvest mistletoe with a silver blade? μηδείς (talk) 04:40, 18 September 2013 (UTC)

The weakness of golden swords is still understated: they would bend under their own weight and/or when swung. I don't have a reference for that, but a rod of lead is about as weak, and not as dense. - ¡Ouch! (^{hurt me} / _{more pain}) 07:38, 18 September 2013 (UTC)

• The initial question from the original poster asked about a shield or sword made of "god", and only later mentioned one made of mere precious metals. If one had a shield or a sword made from 100% Yahweh/Allah, it should be able to protect against any threat, and to destroy any foe, respectively, if one gives credence to the Judeo-Christian-Moslem holy writings. If I went into battle bearing a sword and shield made from any of the manifestations of the Names of God, it would be somewhat confidence-inspiring, compared to the same situation with only a government issue weapon. Edison (talk) 05:54, 18 September 2013 (UTC)

I'll take a government-issue Colt Peacemaker over your manifested superstition any day. See Indiana Jones and the Temple of Doom err, um, Raiders of the Lost Ark. Don't see the other one! ;-). --Stephan Schulz (talk) 06:27, 18 September 2013 (UTC)

Just any colt? I'd rather have The Colt. Ya know...just in case. --Onorem (talk) 17:41, 18 September 2013 (UTC)

So we have the Colt and the occult in the same show ? That's like having the same material be both flammable and inflammable at once. :-) StuRat (talk) 00:32, 22 September 2013 (UTC)

@Count Iblis: Now am I wondering how well a uranium, plutonium or thorium sword would work. Does anyone have an idea? Double sharp (talk) 15:48, 18 September 2013 (UTC)

You've got several factors to consider. 1) Does the material bend or flex too easily (this is gold's problem) 2) Is it study enough? (that is, will it shatter when it hits something else) 3) Will it take an edge. That is, can it produce a cutting edge? --Jayron32 16:47, 18 September 2013 (UTC)

Although a plutonium sword would not be very strong, it would still be particularly dangerous. It is highly radioactive, oxidises easily, and if exposed to moist air, it expands and flakes off as a powder that can spontaneously ignite or at least leave alpha particle emitting flakes all over the place. And if it were to clash with another plutonium sword, it might reach critical mass and explode with a force equivalent to 21,000 tons of TNT. Astronaut (talk) 16:54, 18 September 2013 (UTC)

Without proper confinement and high-speed ballistic convergence, the two swords will at most fizzle, killing bystanders, but not the dragon on the other side of the field. --Stephan Schulz (talk) 17:40, 18 September 2013 (UTC)

It's also horribly toxic on its own (even without radioactivity) so there's that too. Shadowjams (talk) 00:22, 19 September 2013 (UTC)

How about titanium with titanium nitride coating at the outside? It should be strong enough 140.0.229.26 (talk) 12:01, 19 September 2013 (UTC)

Titanium is very light compared to steel - which might be a good thing for a thin rapier where speed is everything - but for most swords, you need enough weight to allow the wind-up for a swing to create the kinetic energy required to do serious damage - and enough momentum to deflect an incoming blow. But even if you embedded a heavy core to get the weight up, the titanium would bend more easily than steel (it's more ductile) and would also chip rather easily. A titanium nitride coating would give it a pretty gold color (although the iridescent color-shifting look of raw titanium is pretty cool too!) - and would possibly help the edge hardness problem - but it wouldn't prevent the sword from bending so easily. SteveBaker (talk) 12:24, 19 September 2013 (UTC)

And what about a sword made from depleted uranium? 24.23.196.85 (talk) 01:28, 20 September 2013 (UTC)

Uranium is heavier than lead - and otherwise has properties similar to raw iron. So I'd expect it to produce a sword that's too heavy to use - and which is considerably worse than a steel sword in other regards. SteveBaker (talk) 18:14, 20 September 2013 (UTC)

Foam nest?

I live on the coast in Washington state. This morning I found something on a tree in my yard. It looks like maybe some kind of nest. It's white-ish pink-ish and soft and kind of gooey. It's about the size of a golf ball. Can you help? — Preceding unsigned comment added by 24.181.128.95 (talk) 21:32, 17 September 2013 (UTC)

It may be one of a few things, depending on how soft it is. If by "foam" you mean bubbly, somewhat sticky liquid then this may be a Spittlebug "nest". If by foam you mean something like an insulation foam, that starts as a sticky liquid but then hardens solid, then it may be a mantis egg-case. Can you please upload a picture? --Dr Dima (talk) 22:36, 17 September 2013 (UTC)

• Praying mantises make foam nests the shape and size of a marsh mallow with a stem through the side. I used to look for them in the fall and keep them in a jar with holes in it in the window over the winter. μηδείς (talk) 04:36, 18 September 2013 (UTC)