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June 10

Evidence that organic food can be unhealthy/health hazard?

In the article for Sewage see reuse in agriculture. Is this evidence that organic food poses a serious health hazard? Please address the context of this subject. No need to try and badlash preservatives/processed food stuffs. Agent of the nine (talk) 14:45, 10 June 2015 (UTC)

The main risk from organic food comes from the use of manure instead of chemical fertilizers. (While chemical fertilizers are often derived from manure, the processing ensures that they are sterilized.) Thus bacterial contamination from the manure is a possibility. There's also a risk to nearby water supplies. StuRat (talk) 14:51, 10 June 2015 (UTC)

So with your comment in mind (StuRat) do you think that wastewater along with "non processed" manure increases the health risk even more? And perhaps in times of drought (like the one in california right now) since the demand for water is always high and the supply is now low maybe farmers might resort to using wastewater at higher frequencies? what do you think?Agent of the nine (talk) 15:53, 10 June 2015 (UTC)

What Stu (or me, or any of us) thinks is irrelevant; we shouldn't be offering un-sourced opinions here. I for one am very skeptical of the claims Stu has made above. If you want a reliable scientific source on food safety of organic foods (including the use of manure), see this recent review article, A Comparison of the Nutritional Value, Sensory Qualities, and Food Safety of Organically and Conventionally Produced Foods . In contrast to what Stu says above, the authors conclude that "There is no evidence that organic foods may be more susceptible to microbiological contamination than conventional foods. "

As for wastewater, here's an entire book: Wastewater irrigation and health - wastewater can indeed be used safely in agriculture, but there are additional risk factors that need to be mitigated, relative to fresh water irrigation. On WP, see Agricultural_wastewater_treatment, Reclaimed_water, and greywater. SemanticMantis (talk) 16:17, 10 June 2015 (UTC)

@semanticmantis. As always thank you for your references. But I dislike EVERYTIME you mention "what anyone thinks is irrelevant". Irrelevant to you maybe but there's nothing wrong with honest conversation in the desire to learn. I care what people think because gaining different perspectives is a part of learning. In no way did I represent my speculation as scientific evidence. Again I look forward reading your references. So you admit because additional steps must be taken to ensure safety of wastewater treatement there is a greater potential health hazard? As long as those steps are taken no problem. But the more steps in a process the greater chance something can go wrong. Your first reference also requires that I download a file to view the contents.. References should not require addtional action to view them let alone downloading something Agent of the nine (talk) 17:05, 10 June 2015 (UTC)

Semanticmantis is quite correct. As it says in the Misplaced Pages:Reference desk/Guidelines "The reference desk is not a chatroom, nor is it a soapbox for promoting individual opinions. Editors should strive to accurately and fairly represent significant views published by reliable sources" Unfortunately, providing references from reliable sources is something StuRat consistently fails to do. Richerman (talk) 17:31, 10 June 2015 (UTC)

(warning, on preview, my language may seem opinionated and snarky - I don't mean to be rude but I also don't want to re-type the whole comment.) Ok, I think that composted manure is perfectly safe. I think manure is much less damaging to agroecosystems than N fertilizers made from fossil fuels and the Haber process, which, together with the chisel plow, have had catastrophic effects on the soil carbon reserves throughout the corn belt of the USA, and also contributed to atmospheric carbon dioxide increases and climate change. I think that my references back up my assertions. I think it is irresponsible to post opinions here that are not backed up by reliable sources. I think that wastewater probably needs more safety measures than freshwater irrigation, but I'm not sure how that comes in to total risk assessment, and I have not yet read the book I linked to. I think that there are many highly educated experts that respond here, and I also think that there are many people who suffer from the Dunning–Kruger_effect. Since we are not in the business of appealing to authority, I think we should be skeptical of claims that are not presented with supporting evidence :)

Now, on the subject of that reference - that is an article in an academic journal, it has been peer reviewed, and is a Review_article. It's about the most trustworthy and expert type of scientific findings we have, and it also appears in a prestigious journal dedicated to comprehensive reviews in the field. The other link is a freely downloadable PDF published by a non-profit scientific research association. Both of these are far more reliable than any WP article or science blog, but you will have to download them. In fact the first article is behind a paywall, but feel free to email me (use talk page link) or ask at WP:REX if you'd like a copy to read yourself. There is absolutely no requirement here or in any scientific discussion that a reference must be freely available on the internet with just one click from anywhere in the world (I agree that it is preferable, but I was not able to find any good, reliable scientific reviews of the topic that are available via open access publication). Just be glad you don't have to actually physically go to an academic library (and be a member), or pay ~$35 per article to read it! I think Academic publishing is a total mess these days, and it is making a few people rich while preventing dissemination of results to the public and to other scientists, but that's a topic for another day... Finally, I might also think that an invisible pink unicorn is out to get me, so please be wary of un-sourced claims by pseudonymous internet people! SemanticMantis (talk) 17:43, 10 June 2015 (UTC)

Well done! quite a retort indeed. I was just hesitant on downloading is all. I'm glad you shared what you THINK =) Since there is so many people in the world would it be reasonable to produce food only organically? Or because there are so many people to feed synthesizing ammonia and other methods you mentioned are the only reasonable way to produce enough food? (so far) AND if you do believe that an invisible pink unicorn is out to get you we can all learn something special about you Agent of the nine (talk) 18:09, 10 June 2015 (UTC)

And without downloading anything it tells you in the abstract "There is no evidence that organic foods may be more susceptible to microbiological contamination than conventional foods". Richerman (talk) 18:14, 10 June 2015 (UTC)

To answer your new question you should read Will Organic Food Fail to Feed the World? the summary of which says "A new meta-analysis suggests farmers should take a hybrid approach to producing enough food for humans while preserving the environment" Richerman (talk) 18:25, 10 June 2015 (UTC)

Additional WP articles at Food_security and sustainable agriculture. These are essentially open questions, and experts in the field still disagree on some issues. Many scientists believe that current agricultural practices cannot be sustained in the long run. Many believe that agronomy research will continue to increase food supply. Many believe that political and social solutions are most apt, as about 1/3 of global food is currently wasted . Here are a few recent science articles that discuss the root of the issue, namely net primary productivity, and how much the world can make . See also the first few refs in each article. First article is paywalled, same deal as before, ask at WP:REX or email me if anyone wants a copy. Also @Agent of the nine:, please have a look at and follow WP:INDENT - this thread has gotten pretty confusing to follow, and it will be easier if you use our indentation style conventions. SemanticMantis (talk) 18:46, 10 June 2015 (UTC)

• What counts as inorganic food? Pop Rocks, Tums, and seltzer water? μηδείς (talk) 18:29, 10 June 2015 (UTC)

Yes, this is a regrettable problem in nomenclature. "Conventional" produce now means "produced with intensive reliance on synthetic pesticides and fertilizers", while "organic" is described at the link below. SemanticMantis (talk) 18:46, 10 June 2015 (UTC)

If you read the intro paragraphs from this page that should answer your question.Agent of the nine (talk) 18:34, 10 June 2015 (UTC)

• Note that if the question is how to best feed the world, avoidance of meat production is key, as it wastes lots of resources. An exception is places unfit for farming, where grazing animals can still survive. StuRat (talk) 18:40, 10 June 2015 (UTC)

I think you mean "unsuitable for arable farming", Stu. Dbfirs 06:58, 11 June 2015 (UTC)

"Arable farming" seems to be British English. I've never heard the phrase used in the US. To me, that's just "farming". We might use the word "farming" to apply to raising animals, but then would make that fact clear, by saying "I own a dairy farm", for example, rather than just "I own a farm". StuRat (talk) 14:51, 12 June 2015 (UTC)

• Here's an article on the risks of manure fertilizer to those living nearby: . And as to the argument that "risks can be handled if the proper steps are taken", of course that's true, but it's also predictable that those steps won't always be followed. Most food poisoning cases would be avoided if the food was prepared correctly, but that doesn't mean we shouldn't try to keep salmonella, listeria, E. coli, etc., out of the food chain, to begin with. And E. coli, in particular, comes from manure. Here's some of the additional safety steps to take when using manure: . StuRat (talk) 21:29, 10 June 2015 (UTC)

That's an article about the risks of living near a (not organic) pig farm, or living near fields where pig manure is used. It is not about the risks of using manure as a fertilizer to grow organic foods. The manure isn't treated properly, and the pigs are fed high doses of antibiotics, leading to antibiotic-resistant bacteria. As a side note, many organic farms do not use manure of any sort, and I've never heard of any using pig manure - it's nasty stuff, here's a guideline saying pig manure should not be used for organic crop production . And none of these finding change the quote I put in bold above - there are plenty of ways to get E. coli and other bugs in conventional crops. Anyway, that is a good ref and an important concern for the safety of conventional pig farming and using pig manure on conventional crops, so thanks for posting. If you had posted that ref in your first post, I wouldn't have given you a hard time. That wasn't so hard, was it? :) SemanticMantis (talk) 14:53, 11 June 2015 (UTC)

In my experience, the word "organic" means "more expensive". Plus you can get some deadly bacteria as a bonus. ←Baseball Bugs carrots→ 22:22, 10 June 2015 (UTC)

If Bugs read Poison on a Plate: Dangers in the Food We Eat and How to Avoid Them he will realize that the potential for dangerous Bugs (no pun intended) are in our supermarkets -regardless of origin. Despite home refrigerators and food and hygiene laws, food poisoning is on the increase because people believe the food they buy is totally safe before the eat by date and so don't abide by there grandmothers simple advice.--Aspro (talk) 23:36, 10 June 2015 (UTC)

So it's just a question of how much you want to pay for that risk. ←Baseball Bugs carrots→ 23:49, 10 June 2015 (UTC)

I would say that it was wiser to invest some time in learning how to mitigate the risk in the first place. Clientèle eating in high-class Michelin star restaurants can and do still suffer food poisoning from time to time. So price doesn’t come into it. --Aspro (talk) 13:10, 11 June 2015 (UTC)

I would note that whether you are reading wikipedia online or a webpage online, you are by definition downloading something. A PDF is not HTML, but it's such a common part of the web that some browsers come with built in PDF viewers and many others have PDFs viewer plugins as standard. Realisiticly the nature of scientific publishing (or really a lot of non ebookj publishing on the web) means that if you are truly interested in science, you really need to learn to deal with PDFs. Nil Einne (talk) 21:32, 11 June 2015 (UTC)

• I am sorry if I missed it, but what is this "grandmother's simple advice" to which you refer, Aspro? My neighbor's grandmother was infamous for advising "just eat around the green parts" while my own father's mother said adding sugar will "take care of it." μηδείς (talk) 04:42, 12 June 2015 (UTC)

@μηδείς. A few memories are still etched into my failing and ossified mind: Don't store cooked food with raw nor prepare them together. Wipe down and scrap chopping boards after you use them and leave to dry (rapid desiccation kills bacteria before they can become dormant spores). Always wash hands between tasks. Wash hands frequently with coal tar soap AND a nail brush. Wash your hands always after going to the loo. Don't allow anyone in the kitchen with a whitlow. Lime wash the inside of ones larder each year (these where rooms we used before refrigerators and lime wash is a steradent ) . Pluck and eviscerate chickens and other animals out in the outhouse -not in the kitchen. If fish and chicken are prepared at the same time and the fish start to smell off – don't eat the chicken. (I only found out recently that the bacteria that give the off smell to fish is not pathogenic but the chicken stored at the same temperature will more than likely be teeming with dangerous bug. Yet, not smell off) Etc... If I broke any of these rules I would have got get a clip round the lughole. 'You' may know that they make sense yet I see people today (in this modern world of antibiotics ) demonstrably brake these rules every day, only to then blame the food suppler if they fall ill. Ready prepared and sliced salad vegetables, is another daft innovation, as far as food hygiene goes. I am not saying organic food don't have any health hazards at all. After all a sack of organic spuds dropping on one's head from a great height may give one a server headache.--Aspro (talk) 14:06, 12 June 2015 (UTC) --Aspro (talk) 14:06, 12 June 2015 (UTC)

Thanks, Aspro but I am actually a trained head cook, as well as well versed in biology. The stories above were not advice, but scary/funny anecdotes. I find dealing with other people's cooking habits difficult. For example, my father will make ham and bean soup, boil the pot all day, then take off the lid to let it cool on the stove for six hours before putting it in the fridge so that he doesn't heat the refrigerator up.

Not only does he leave it uncovered, he pours unused soup back in. I have told him repeatedly that allowing it to sit open until it achieves room temperature simply allows germs to colonize it. I have told him repeatedly food comes out of the cookware, it never goes back in, and that if he left the pot covered when it was still at a boil the insides would be sterile until he removed the lid. He could safely leave the covered pot on the stove over night to cool. (See perpetual stew, not the most helpful of sources, though.)

My mother, on the other hand, automatically throws out all food that's two days old, including pickled items and chinese mustard and hot peppers, which are in effect self-preservatives, and milk that's not gone bad. That is part of her nesting regimen which requires her to throw out heirlooms and to get new carpeting and furniture every 2-5 years.

@μηδείς Agree that is not a recommended bean and ham soup method for today but as he is still making it and not pushing up the daisies it might come back to biology again. The obvious thing that springs to mind to explain why he has gotten away with it so long is that he adds the unused soup whilst the main pot is hot enough to bring it up above 65°. Also, the sort of bacteria laden mots floating about in the kitchen are also more likely to only inoculate it with bacteria that produce heat liable toxins which will be destroyed on reheating. I don't know if cooked garlic and herbs have the same antimicrobial effect when raw but they may also have an effect. If the ham is not lean and a layer of fat floats on the surface that can also act as a bacterial barrier. Fat and aspic as you will know, was often used to preserve food for the short term. Potted shrimps ( in butter) keep for days. Oh gosh. All this is making me feel I'm hungry. The OP question was about organic food and my point is: That 'anything' that supports bacterial growth has to be treated with respect and a few simple rules mitigate almost all of them. Of the remainder, food hygiene practices prevent anthrax and other nasties form getting into the food chain.--Aspro (talk) 20:55, 12 June 2015 (UTC)

I get "server headaches" all the time. :-) One of the most common sense pieces of advice which now seems to be ignored is "examine your food before you cook it or eat it". People now seem to rely exclusively on the date on the package, and if the date is good they are sure it's fine, whether it smells or tastes bad, has gone cloudy, changed color, grown fuzz, or is teeming with maggots. StuRat (talk) 14:40, 12 June 2015 (UTC)

Yes, Stu. My mother is the opposite side of that coin. She throws everything out on the expiration date. I have tried to convince her that spoiling a physical change, not a magical hour at which your coach changes back into a pumpkin. μηδείς (talk) 15:11, 12 June 2015 (UTC)

Same here. I can't convince her that the date is almost meaningless, as the conditions under which the item is stored make it last 10 times as long or 1/10th as long. Although she does have the bad habit of taking the lids off of anything she might use for the meal, and leaving them off the the entire meal, ensuring they get a proper dose of airborne bacteria. If I am going to use spaghetti sauce, for example, I open it, immediately pour out what I need, then the lid goes right back on. StuRat (talk) 15:53, 12 June 2015 (UTC)

I think it's funny that certain posters (usually admins) say that WP is not a chat room or a soap box. however that rule seems almost entirely uninforced. oh the LOLZ just look at what my post turned into!! Agent of the nine (talk) 16:15, 12 June 2015 (UTC)

Arabian desert

If the outflow of the Jordan river, Euphrates and Tigris was diverted towards the Arabian desert, could a majority of the desert eventually turn green? 84.13.148.183 (talk) 18:27, 10 June 2015 (UTC)

The question would be whether the outflow would exceed the evaporation rate. In reality, it would certainly exceed the evaporation rate until the lake formed had a large enough of a surface area to equal the flow rate. So, you would get a terminal lake of some size which would become saltier and saltier until the salts started to precipitate out of solution, ending up with something very much like the Dead Sea. StuRat (talk) 18:38, 10 June 2015 (UTC)

In other words, it is impossible to turn the Arabian desert green. 84.13.148.183 (talk) 19:51, 10 June 2015 (UTC)

If all of humanity were willing to set this as our top priority, I'm sure we could get it done. So, in that sense it's possible. But practical, no. See Salton Sea for an example of how something similar happened accidentally. StuRat (talk) 21:14, 10 June 2015 (UTC)

It's not impossible. THIS could be used to turn the arabian desert green. Agent of the nine (talk) 20:06, 10 June 2015 (UTC)

It may be possible with a proper irrigation system - but it takes a lot of work see Richerman (talk) 21:28, 10 June 2015 (UTC)

This is not a purely hypothetical question and it does not require speculative answers. The science of hydrology exactly quantifies how much water flows out of a river. In particular, the Tigris, Euphrates, and Jordan rivers have been extensively studied.

• Here is a summary study from Professor James Lee of American University: the Tigris-Euphrates River Dispute at the website for The Inventory of Conflict & Environment.
• From the same department, the Jordan River Dispute,including a political history summary, and a quantitative review of water use, population requirements, and river outflow.
• The water from the Jordan River has been diverted since the 1967 War. In fact, many historians consider the National Water Carrier of Israel, which diverted water into Israeli-occupied territory, to be a causative precursor to the war. There is barely enough water to keep the Jordan River valley and the Sea of Galilee at their present levels.
• Here is a study from the Yale School of Forestry and Environmental Studies on engineering impacts: Restructuring of Water Usage in the Tigris-Euphrates Basin: The Impact of Modern Water Management Policies. This provides a good scientific overview.

Diversion of the outflow from these rivers would not supply enough water to irrigate the entire Arabian desert. Not only is this an impracticality from a quantitative, civil engineering standpoint - it's also a complete no-go from the perspective of political science and international relations. The users of water from these rivers have actually gone to war repeatedly over small engineered changes in flow rates of the water. Multiple horrific wars have been fought over lesser rivers.

Nimur (talk) 23:11, 10 June 2015 (UTC)

Will the Great Attractor beat Dark Energy?

I.e. will we implode into the Laniakea Supercluster, or be torn from it by Dark energy? Hcobb (talk) 23:12, 10 June 2015 (UTC)

Yes. ←Baseball Bugs carrots→ 23:49, 10 June 2015 (UTC)

The dark energy can be thought of as an acceleration of Λ·r where Λ ≈ 4·10 s (I think—I may be off by a factor of 2 or 3). Taking 5·10 M_Sun as the mass of the great attractor and 200 MpcMly as the distance, that gives an acceleration of 8·10 m/s (outward) from dark energy and 2·10 m/s (inward) from the great attractor. -- BenRG (talk) 12:17, 11 June 2015 (UTC)

Sorry, my numbers were wonky—now improved. I doubled the acceleration from Λ because it applies to both objects equally, whereas the Great Attractor's attraction is one-way (it being much more massive than the Milky Way). -- BenRG (talk) 18:39, 11 June 2015 (UTC)

Laniakea Supercluster is not gravitationally bound, it is clear from the discovery paper. Ruslik_Zero 17:35, 11 June 2015 (UTC)

June 11

Why do some people claim to enjoy bitter flavours?

My understanding is that aversion to bitterness is an evolutionarily-conserved trait but adults purport to enjoy bitter coffee or beer or lager. Are they pretending to like it until their response changes or did something "go wrong" in their genetic combination and development into adults? --78.148.104.33 (talk) 01:43, 11 June 2015 (UTC)

Are you the same one that asked why other like jazz when you don't? ←Baseball Bugs carrots→ 01:46, 11 June 2015 (UTC)

No, I'm not but I don't see how this is related. I don't know how a person comes to like the music that they do but I'm talking about tastes in which I expect a similar response across many mammals that developed a sense of bitter taste. 78.148.104.33 (talk) 02:33, 11 June 2015 (UTC)

The enjoyment, or not, of the taste of anything surely has to have at least some genetic factor. In last month's interview with David Letterman, he said that he tried Scotch when he was about 11, and it was delicious - he couldn't get enough of it. In contrast, I don't like alcohol, never have. But there could be environmental factors too. ←Baseball Bugs carrots→ 05:07, 11 June 2015 (UTC)

De gustibus non est disputandum as they say. Gandalf61 (talk) 05:58, 11 June 2015 (UTC)

The untranslated Hebrew in that article is especially helpful. NOT (as they say). — Preceding unsigned comment added by Baseball Bugs (talk • contribs) 08:31, 11 June 2015 (UTC)

In case it isn't obvious, there are two common definitions for the worse "taste." The question is using the definition of a triggering specific taste buds on the tongue. Specific taste buds trigger the "bitter" taste. The rebuttal and quote use a completely different definition of what a person claims to enjoy. That is purely psychological. There is no relationship between something such as "taste in music" and "sensation of a bitter taste on the tongue." 209.149.113.240 (talk) 13:18, 11 June 2015 (UTC)

The evolution issue is that bitter foods may be poisonous, so are best to be avoided, unless you know they are safe, or are starving and willing to take the risk. So, initial avoidance makes sense, maybe with just a small taste. Then, if there are no ill effects, it makes sense to try a bit more, etc., until it is established as safe. This translates into "developing a taste" for initially unpleasant foods. StuRat (talk) 03:26, 11 June 2015 (UTC)

Shockingly, the usual reason people claim to enjoy something is because they actually enjoy it. Why do you assume they must be lying, or that something must be 'wrong'? AlexTiefling (talk) 10:02, 11 June 2015 (UTC)

Perhaps the question is asking about peer pressure. Everyone at work says they love coffee. Do you say that you find it rather disgusting to ruin a good cup of hot water with ground up tree poop? Of course not. You lie and say you enjoy it also. What if everyone was telling a lie and everyone secretly disliked it? I believe that is what the question is asking. 209.149.113.240 (talk) 13:21, 11 June 2015 (UTC)

Where did you get the idea that a plant's fruits and seeds are excrement? ←Baseball Bugs carrots→ 17:17, 11 June 2015 (UTC)

Yes, technically I'm sipping hot water steeped with ground up shrub embryos and endosperm. OP would probably like this recent XKCD cartoon . SemanticMantis (talk) 20:42, 11 June 2015 (UTC)

Right. Those are not excrement. Technically, a plant's excrement would be oxygen, among other things. The cartoon is funny. But I know people who like beer, so it's not a myth. ←Baseball Bugs carrots→ 21:22, 11 June 2015 (UTC)

I believe that it has to do with accustomisation. In my younger years, I hated grapefruit, coffee, and brandy, and now I exceedingly enjoy all three. It is not a case of me liking the bitterness, so much as it doesn't bother me anymore. Initially I hated the bitterness in coffee, and took my coffee with almost as much milk as coffee drank. As my sense of taste matured, I started to phase out milk and sugar from my coffee. Before long, I noticed that I was adding so little that I might as well leave it out entirely. To my pleasant surprise, I was correct, and was no longer bothered by the bitterness. In fact, I now prefer a double Ristretto when visiting a barista. Not only that, but I found that my general tolerance has increased for other traditionally bitter consumables. However, I can only tolerate bitterness, if there is an accompanying taste reward. For instance, grapefruit are both bitter and sweet. I enjoy grapefruit not for their bitterness, but for the other taste. I suspect that it is the same for other people, how much bitterness are they willing to endure for a reward. I hate absinthe, not because it's bitter, but because the taste of wormwood and anise is not much of comparative reward in my books. I don't think anyone would like the taste of aloe sap, for the same reason. Plasmic Physics (talk) 11:34, 11 June 2015 (UTC)

Genetics can have something to do with it sometimes, because when I was younger I was definitely a Supertaster. Even today, I can not (no-way!) eat for example Momordica charantia.--Aspro (talk) 13:35, 11 June 2015 (UTC)

• This basically comes down to the difference between a flavor and a taste. Virtually nobody enjoys a pure bitter taste, but a flavor is a combination of a taste with odor and other factors. People can learn to like specific bitter flavors if they are associated with rewarding things. Tonic water, for example, contains quite a large amount of sugar, which is intrinsically rewarding. Coffee contains caffeine, a rewarding stimulant, as well as oils that give it a pleasant odor. Looie496 (talk) 13:48, 11 June 2015 (UTC)

• Not only the difference between flavour and tatste, but also acquired "tastes". Most people dislike coffee, alcohol, and cigarettes the first time they try them, but they come to associate the taste with the ensuant rush. μηδείς (talk) 01:11, 12 June 2015 (UTC)

There are plenty of people (myself included) who clearly do enjoy these flavors. Sure, it's possible to suggest that these people are merely pretending to like them for some kind of bizarre social reason - but enough people consume foods and beverages with those flavors when there is nobody else around to impress that it's hard to claim that they don't really enjoy them.

In the case of coffee and beer, parents generally keep those things away from small children, so there is no ability to become accustomed to those flavors in early childhood. When they become teenagers, they might experiment with them - and probably will find them distasteful initially - but social pressure may force them to continue to try until a taste for them develops.

The question here is whether the 'learned response' that's clearly going on here is:

1. That the initial distaste was learned (in effect) by preventing the senses from learning that these flavors are OK to consume in early childhood, and that this is conditioning is overridden by social pressure in later life ("unlearned")...OR...
2. That there is an inborn instinctive/genetic bias against these flavors that we learn to override later in life.

It's not easy to tell which of those things it is. I recall a study (sorry, can't find the link) that showed that even in the womb, babies somehow learn the flavors present in local cuisines and are born with preferences for those kinds of foods. Notably, children in India are happy to eat strong flavored curry from a very young age, where children born in Europe and America are most definitely NOT happy to do that. This is true even if a child born in India is adopted into a western-culture before they start eating solid foods...but it is not true of children of those adoptees. This says that the preference for those flavors is learned from the mother and is not genetic in nature. However, since we now advice pregnant women not to consume coffee or alcohol, this might well result in a change in preferences in the following generations. SteveBaker (talk) 13:25, 12 June 2015 (UTC)

The argument might make sense if there were some bitter tasting substance (not a condiment) that people consumed on its own with no psychological effect. For example, I like horseradish, but only as an accompaniment to meat whose taste it compliments. Is there some drink like beer or coffee that people consume without ever having had alcoholic beer or caffeinated coffee first? μηδείς (talk) 18:53, 12 June 2015 (UTC)

The ristretto that I mentioned earlier, actually contains less caffeine than a cappuccino. Normally, caffeine content does not even factor at all for me. I just prefer caf over decaf, because the decaf process detracts from the flavour. Plasmic Physics (talk) 12:11, 13 June 2015 (UTC)

Flying in Mars

Could a plane of some kind fly on Mars? Or a zeppelin float?

The atmosphere is much thinner there, but so is the gravitational force. And the atmospheric pressure you would have to deal with in the case of the zeppelin is much lower lower. Hydrogen is less dense than the CO2 that makes the Atmosphere of Mars.--Abaget (talk) 17:30, 11 June 2015 (UTC)

NASA Langley's ARES program designed an aircraft for use on Mars. You can read our article, Aerial Regional-scale Environmental Survey, for an overview of the aerodynamic challenges. In 2013, the mission was cancelled in favor of MAVEN, an orbital spacecraft. Evidently, NASA's upper management does not believe that the scientific benefits of an aerodynamic flying platform on Mars are worth the costs and risks at this time. However, perhaps at some time in the future, new technology or new scientific research objectives will reopen this avenue of exploration. Nimur (talk) 17:53, 11 June 2015 (UTC)

For a more humours but still serious discussion on the subject, see xkcd "What if?" on Interplanetary Cessna. WegianWarrior (talk) 18:04, 11 June 2015 (UTC)

An enlightening aspect of that source was the statement that Titan has "surface pressure only 50% higher than Earth’s with air four times as dense." This is because its atmosphere (largely nitrogen like ours) is at only 1/3 the Kelvin temperature! (Ideal gas law) This would also be a factor in favor of Mars flight, but not to the same degree. I'm guessing that air resistance should depend on the pressure and mass, but lift should depend only on mass? No, wait... I better not spout off on this one, Nimur might put me in the stocks. Wnt (talk) 19:29, 11 June 2015 (UTC)

Lift also depends on air temperature and air pressure. Because the atmosphere of Mars is so different than Earth, if you want to accurately estimate lift generation, you also need to account for the fact that the air pressure is produced by different species of gas molecules. To engineer an aircraft for such an atmosphere is deep into the territory of poorly explored aerospace engineering: there have not many empirical studies of airfoil performance characteristics in any atmosphere that is anywhere remotely near to Mars' near-surface environment. The ARES team published Mars Airplane Airfoil Design with Application to ARES (2003) summarizing their research to that time.

For most purposes, aircraft performance is "equivalent" when density altitude is "equivalent." Density Altitude (on Earth) accounts for pressure, temperature, humidity, sea level pressure, and true altitude above sea level. On other planets, one could construct a "density altitude equivalent". To complicate matters, we do not have great weather prediction capability for other planets: we don't have dense networks of ground- and satellite- weather observations; nor do we have centuries of meteorological experience and theory. Local atmospheric weather variations on Mars are known to deviate up to 20% (nominally) from our "best" Mars weather models: so we would need to over-design the aircraft performance to handle worst-case pressure, wind, and so on.

It's a fascinating topic; it's worthy of many years of study and depends on a lot of prior understanding about spaceflight and aeronautics. One of the key troubles with the Project Apollo Lunar Roving Vehicle was the persistent belief by many outsiders that it would be a "simple" engineering challenge analogous to building an (electric) automobile on Earth. Boeing spent considerable advertising effort to remind everyone involved that this vehicle was actually a manned spacecraft, not a mere golf cart: it had to be built on Earth, transported through space, and survive with all its functionality intact, and then to operate on another world. (I'm thinking of a specific and very memorable color brochure/pamphlet published by either GM or Boeing, but I can't find it at ALSJ's Lunar Rover document archive). So, when we talk about operating an aircraft on Mars on in the atmosphere of some other planet, it's very easy to overlook how very complicated the process is. Not only does the aircraft need significant engineering for the unique conditions at Mars - it also must survive the journey to Mars, within the realistic constraints of dollar budget, fuel budget, mass budget, energy budget, and the risk/reliability envelope!

I don't think we can adequately summarize all of the engineering challenges except to point any interested reader towards the massive amount of available information from NASA's planetary sciences programs. The ARES mission is a good starting place, as it is the most recent major serious effort to design an aircraft for extraterrestrial operation.

Nimur (talk) 19:53, 11 June 2015 (UTC)

I agree that the ARES study is the "go-to" place to find the latest research. Winged or rotor-driven flying machines are be tricky but not impossible on Mars. A "sufficiently large" balloon should work - but it might need to be huge to have any useful payload. Most of Mars' atmosphere is CO2, which is really heavy - even a balloon filled with normal Earthlike air should be able to float. The problem is with "sufficiently large" because Mars' atmosphere is pretty thin - so you'd need a lot of volume to displace enough atmosphere to counteract the weight of the balloon itself. The problem is that with the air being so thin, and yet have fairly large wind speeds is that you really need rockets rather than jets or propellers to get thrust and to keep control of the thing - the need to provide reaction mass means that you're unlikely to be able to build something that is solar powered or electrical in nature - and then you're back to chemical rockets that aren't sustainable for a long duration exploratory flight. One of the weirder ideas is a gas filled balloon that moves around by hopping and bouncing (possibly to impressive heights) which could use this occasional contact with the ground to provide thrust and some kind of steering. Gyroscopes could provide orientation control while up in the air. SteveBaker (talk) 13:06, 12 June 2015 (UTC)

• Martian surface gravity is ⅜ of Earth standard, but the air pressure is far less than ⅜ of Earth's. —Tamfang (talk) 05:30, 13 June 2015 (UTC)

Dr. Charles Drew car accident

Who are the 3 doctors that were in the car when Dr. Charles Drew had his accident? What are their bios? Are there any articles on these other 3 doctors? I believe one of them was Dr. Walter R. Johnson, from Washington D.C. — Preceding unsigned comment added by 172.56.10.47 (talk) 23:47, 11 June 2015 (UTC)

See Charles R. Drew for our article. According to this article from NCBI, which goes into quite a bit of detail about the accident, the other passengers in the car were Walter Johnson, Sam Bullock (the owner of the car, although Drew was driving), and John Ford. Tevildo (talk) 01:14, 12 June 2015 (UTC)

This is Dr Bullock's obituary. The best information I can find so far on Dr Ford is in the NCBI article. Research is continuing. Tevildo (talk) 01:47, 12 June 2015 (UTC)

Does anyone else notice that Charles Drew is supposed to be black, but doesn't appear to be so in the pics in our article ? StuRat (talk) 17:49, 13 June 2015 (UTC)

This page has several photos of him that, shall we say, indicate his heritage more definitely (in particular, this one - high resolution). See also one-drop rule. . Tevildo (talk) 18:44, 13 June 2015 (UTC)

June 12

Energy

Can "Dark energy" be converted into useful electrical energy by a generator?182.185.56.56 (talk) 11:51, 12 June 2015 (UTC)

We don't even know what dark energy is yet, or even if it exists for that matter. Plasmic Physics (talk) 12:11, 12 June 2015 (UTC)

What is clear is that the stuff doesn't appear to interact with normal matter at small scales - if it did, we'd have noticed and categorized it a very long time ago. That's a bad sign for anyone thinking of extracting useful energy from it.

It's really only detectable at the scales of galaxies where something out there definitely has a gravitational pull that is measurable. But no, right now we know so little about dark matter and dark energy that we certainly can't use it for anything yet. Whether we could eventually use it to power stuff is a total unknown at this point. Anyone who says otherwise is almost certainly a member of the loonie wing of the "free energy" movement - and belongs in the same category as those who believe we can get energy from Zero point energy, Simple Magnetic Overunity Toy, Perpetual motion machines, Casimir effect generators, Water fuelled cars, etc, etc. SteveBaker (talk) 12:51, 12 June 2015 (UTC)

There are legitimately scientific ideas about how the Casimir effect could be used to stabalise an Einstein Rosen wormhole. Plasmic Physics (talk) 13:07, 12 June 2015 (UTC)

Would you care to cite these ideas by referencing legitimate, peer-reviewed scientific publications? Nimur (talk) 14:51, 12 June 2015 (UTC)

I'm out of my element here, and perhaps way off base, but these legitimate, peer-reviewed articles seem relevant to PP's claim: , . This guy is arguing against such a possibility - but he does acknowledge that it is a somewhat serious idea that real scientists have seriously investigated. SemanticMantis (talk) 15:51, 12 June 2015 (UTC)

The problem is that "dark energy" is a misnomer. It is just the lambda term in the Einstein equations. So, I am not sure it represents any real energy. Ruslik_Zero 20:31, 12 June 2015 (UTC)

Misuse of medication

Oldest fossil of MODERN humans

what is the oldest fossil of MODERN Humans. — Preceding unsigned comment added by A8v (talk • contribs) 21:15, 12 June 2015 (UTC)

I think THIS is what you are looking for. Agent of the nine (talk) 21:19, 12 June 2015 (UTC)

We have an article on Anatomically modern humans.--Aspro (talk) 21:28, 12 June 2015 (UTC)

June 13

Why do some people die of cigarette smoking but others live to long ages?

Assuming they smoke at the same rate. Why? 69.121.131.137 (talk) 14:39, 13 June 2015 (UTC)

Why do some people who go for a walk in the savannah get eaten by lions while others survive untouched? Smoking increases your probability of developing certain medical conditions. See risk factor. – iridescent 15:07, 13 June 2015 (UTC)

A more interesting question might be why chain smokers can die from such a variety of ailments: cancer, emphysema, COPD, stroke, heart attack, etc. The bad stuff in the smoke affects different people different ways. ←Baseball Bugs carrots→ 20:16, 13 June 2015 (UTC)

That probably relates to the large number of toxic substances in cigarette smoke. Carcinogens, mutagens, and chemical irritants. StuRat (talk) 10:43, 14 June 2015 (UTC)

That suggests genetic predisposition to one or more of those things. You can get any of those things without having been a smoker. Maybe smoking just ratchets up the probability exponentially. ←Baseball Bugs carrots→ 11:31, 14 June 2015 (UTC)

Genetics may play a factor, but it's not the only reason people are affected differently any more than someone being killed by a lion or hippo is just because of genetics. As for your last point, isn't that what Iridescent's reply said? (Well not necessarily exponentially.) Nil Einne (talk) 11:37, 14 June 2015 (UTC)

People get eaten by lions because of dumb luck. People die of smoking while others live to extremely old ages because of a physical reason, not dumb luck. 69.121.131.137 (talk) 11:38, 14 June 2015 (UTC)

Is PTSD considered a learning disability?

Just wondering. — Preceding unsigned comment added by 24.20.204.170 (talk) 19:32, 13 June 2015 (UTC)

Considered by whom? Probably the most authoritative reference material for such questions is the DSM V, published on behalf of the American Psychiatric Association. The PTSD Fact Sheet expressly states that post-traumatic stress disorder now deserves its own chapter, because it is no longer classed as an anxiety disorder (as it was in the previous edition, DSM IV). Neither the former nor the current classification of PTSD places it alongside "learning disorders," which are typically classed as either an intellectual disability or other Specific Learning Disorders.

Here is another ser of worthwhile reading: Psychiatric comorbidity: is more less? (2004) and Comorbidity in psychiatry: Way forward or a conundrum? (2006) "The traditional practice of understanding and explaining all the symptoms and signs of a person presenting to mental health facilities was synchronous with the hierarchical system of classification. The clinical dictum of ‘one person one diagnosis’ was in keeping with the early classification systems wherein the diagnostic groups were arranged in hierarchy..." ..."The current systems of DSM-IV and ICD-10 actively encourage multiple diagnoses in the same person, regardless of the possible contribution to aetiology, allowing the maximum amount of diagnostic information." In other words, the present norm in clinical psychiatry is to diagnose PTSD and other syndromes or diseases if symptoms are present that pertain to multiple diagnoses, irrespective of whether the cause of the symptoms is related. Not every clinical psychatrist favors this norm.

Nimur (talk) 19:42, 13 June 2015 (UTC)

See Posttraumatic stress disorder and Learning disability. Our articles, which refer to and reflect DSM IV, DSM V, and the ICD (which is considered the authoritative source in Europe), do not say anything about PTSD being a learning diability. The symptoms and effects of PTSD have a scope that goes beyond learning, and a diagnosis of a learning disability would be incorrect if the learning disability is part of the pattern of PTSD. Robert McClenon (talk) 19:51, 13 June 2015 (UTC)

If someone breaks both arms and is unable to write, they'll be unable to take notes in class - and will presumably find it harder to learn. Do we consider a broken arm to be a "learning disorder"? No, we don't. Does having both arms broken make it harder to learn? Yes, it does. Heck, having a common cold makes it harder to learn. So it's perfectly possible (indeed HIGHLY likely) that someone with the more profound symptoms of PTSD will find it harder to learn - but that doesn't make PTSD a "learning disorder" per se. SteveBaker (talk) 01:54, 14 June 2015 (UTC)

June 14

What kind of plant is this?

Wisdom tooth timing

So if wisdom teeth assisted our prehistoric ancestors in chewing, one would expect that such teeth should emerge roughly at the same time as other permanent teeth - I don't think the prehistoric men switched to another diet in their 20s or so, to warrant wisdom teeth so late. I.e., the ancestors would have needed wisdom teeth already in their teens at least, but now there's a significant timing difference - my sister had her first wisdom teeth around 18, others in their late 20s, etc. Maybe there was a different timing of wisdom teeth back then and later it evolutionarily shifted when such teeth became redundant? Brandmeister 11:49, 14 June 2015 (UTC)

I'd expect that wisdom teeth were to replace other permanent molars that were no longer effective. Back then, with lots of sand and grit getting in the food, teeth would wear down more quickly than they do now. StuRat (talk) 12:08, 14 June 2015 (UTC)

@StuRat: I have to call "citation needed" on that! Since wisdom teeth typically come in before age 25, and wear typically affects the tops of the teeth without allowing them to come closer together. Wisdom tooth explains that there are quite significant racial differences in their occurrence. Some people, myself included, get them quite early. Wnt (talk) 12:40, 14 June 2015 (UTC)

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