Wikipedia:Reference desk/Archives/Science/2010 July 5

= July 5 =

Giant isopod-- survival outside of water
Can a giant isopod survive on land? If so, for how long? (I ask because I've seen photos of them on land and apparently alive, such as [this], unless it's fake). 68.123.238.146 (talk) 03:22, 5 July 2010 (UTC)


 * That photo is definitely a fake. The trilobites vanished in the Permian extinction about 250 million years ago.  The ICanHazCheezburger.com site is all about faked photos of one kind or another.  Modern isopods are things like wood lice - but there is the Giant isopod Bathynomus - that can grow to a half meter or more in length.  They live in very deep ocean areas though - I don't think they'd do well out of water. SteveBaker (talk) 04:35, 5 July 2010 (UTC)
 * So I can buy realistic plastic Trilobites?




 * ...Excellent... --mboverload @ 04:39, 5 July 2010 (UTC)


 * I don't think the OP is confused about trilobites. The animals in the picture are clearly giant isopods despite the caption, and the OP asks about the survival of giant isopods out of water. Rckrone (talk) 07:19, 6 July 2010 (UTC)
 * They're images of giant isopods (which are common enough) who've been exposed to snack foods and Photoshop.  Acroterion  (talk)  20:03, 6 July 2010 (UTC)
 * Considering that our Giant isopod article has a couple of pictures of them out of water (apparently alive), I would imagine that they can live a short time out of water. They're related to crab and lobsters (being crustaceans), which are also known to be able to survive outside of water (in some cases, for extended periods of time).  A giant isopod probably couldn't function very well out of water (being used to having water help support its weight), but they might be able to avoid the quick suffocation that most fish would experience. Buddy431 (talk) 23:46, 6 July 2010 (UTC)
 * On which general topic see Gérard de Nerval. 87.81.230.195 (talk) 09:17, 7 July 2010 (UTC)
 * I thought most deep-sea creatures couldn't even survive in shallow water, never mind air? Strange.--92.251.137.196 (talk) 15:22, 7 July 2010 (UTC)

Ancient Machines
This site seems to be deliberately laid about yarn. They mention a "University of Chandigarh" which does not exist. The guy who made this up knew that there is a town called Chandigarh in India allright so thought that must have uni too ! There may be other loopholes too that need to be exposed  Jon Ascton    (talk)  03:42, 5 July 2010 (UTC)
 * Sorry, don't understand your question. Laid about yarn? --mboverload @ 04:13, 5 July 2010 (UTC)
 * I think he's stringing you along:) Myles325a (talk) 08:10, 5 July 2010 (UTC)
 * (EC) My guess is that the university is a self-made non-accredited diploma mill, as pretty much no credible scholar would entertain the so-called ancient astronauts theories. Not even the champion of the hypothesis in Chariots of the Gods? has much of anything in the way of credentials. In other words, academia is immune to this nonsense, but the public isn't, especially when this kind of trash appears on National Geographic channel's Is It Real? see critique. Alas, pseudoscience runs strong still, but we can take comfort that cocaine/opium or worse brain tonics aren't sold every which-way in every CVS nowadays, as would be in the late 19th century. SamuelRiv (talk) 04:16, 5 July 2010 (UTC)
 * Excuse me but there is no need to begin to bad mouth a university or an individual because a 'new-ager' has mentioned it/them in one of their 'new-age' articles. Please do some research before jumping to conclusions, both SamuelRiv and JonAscton. Thank you.87.102.23.18 (talk) 15:28, 5 July 2010 (UTC)
 * Just to clarify the scholar was Dr. Ruth Reyna who obtained a PhD from University of Poona 1961, (also written books eg amazon link). The Chandigarh university appears to be Panjab University, and the documents are supposedly held there . I don't know where the documents come from or anything about their authenticity. 87.102.23.18 (talk) 15:23, 5 July 2010 (UTC)
 * I assume these are the documents ?
 * Hypothetical Example I have a crackpot theory that the observable universe is explained by tiny silver men inside my eyeballs casting shadows on my retina, and by invisble golden mice jumping up and down on my head to simulate gravity.. In my article I reference Isaac Newton's work on optics and gravity .. Science is not advanced by attempting to discredit the work of Newton, or Cambridge University simply because I mentioned them in my blog..87.102.23.18 (talk) 15:44, 5 July 2010 (UTC)

I don't understand the question here. The "strange artefacts" site is obviously just another conspiracy theory site, not to be read when sober. anything else? Physchim62 (talk) 16:01, 5 July 2010 (UTC)
 * I think the aim is to show some flaw - I would guess that dating the documents would be one obvious route to disproving the 'ancient astronaut' theory. If the documents prove to be old then that would be a suprise too.87.102.23.18 (talk) 16:08, 5 July 2010 (UTC)


 * To IP87: fair enough, the fault is mine. Regarding the original question, I hope I answered that with the links in my first response which discuss the whole history of the ancient astronauts kookery. Regarding the "documents" linked, they are actually modern drawings of what are assumed to be descriptions of flying machines in one of the Vedas, if I recall from a badastronomy.com debunking. It's like if I were to draw a picture of Noah's Ark, except I assume beforehand that it's actually a spaceship. SamuelRiv (talk) 16:12, 5 July 2010 (UTC)
 * Additionally there's no shortage of flying machines/people/creatures in many other ancient texts (along with gold growing rings, cloaks of invisibility etc etc) . Many people require more than just some text describing space travel to make them believe that it's literally true. The usual requirement for a historical document to be taken seriously as containing elements of fact is supporting evidence, usually archaeological remains, or secondary independant documents corroborating (eg such as matches in historical events/people in the bible and in eqyptian historical sources). 87.102.23.18 (talk) 16:47, 5 July 2010 (UTC)

Could you clone a human female from male cells?
As a male cell contains both an X (female) chromosome and a Y (male) chromosome, would it be possible to pair up two of the X chromosomes and create a human female from the male's genome? And if a boy was cloned (XY) as well as a girl (XX), could the two of them theoretically breed and start a population that derives from a single parent? I am supposing that human females can't do this because they do not have a Y chromosome. We are used to thinking that only females can create life, but the whole cloning idea is reminiscent of the Genesis story in which Eve is created from Adam's body, and not vice versa.Myles325a (talk) 08:28, 5 July 2010 (UTC)
 * I am not used to thinking that only females can create life. Cuddlyable3 (talk) 13:11, 5 July 2010 (UTC)


 * I suppose it might be possible, in theory, to remove the Y chromosome and duplicate the X chromosome to create a female "clone" from a male cell. But that cell now has two identical X chromosomes, so any recessive genes on the X chromosome have been duplicated, which will reduce the chances of the "clone" developing normally. Similarly, mating clones will result in a population with very low genetic diversity, which leads to low fertility rates. Gandalf61 (talk) 13:27, 5 July 2010 (UTC)


 * Was it Asimov who sang, "Oh give me a clone, of my own flesh and bone, with its Y chromosome changed to X. And when it is born, my own little clone, will be of the opposite sex."? -- 58.147.52.176 (talk) 12:17, 6 July 2010 (UTC)
 * Another science fiction reference is that of Lapis Lazuli and Lorelei Lee, daughters by this process of Lazarus Long in Heinlein's Time Enough for Love. -- 58.147.52.176 (talk) 23:40, 6 July 2010 (UTC)


 * The uniparental disomy article may be of interest, although it does not specifically address this issue. -- 58.147.52.176 (talk) 23:40, 6 July 2010 (UTC)

Strange hydrostatic aroud Australia
Hello dear thinkers. Please excuse my uneasy English, I'm French. For those who prefer the French version, here it is.

On this page Australie : nouvel état des lieux du réchauffement climatique they are explainations concerning the rise of water of the oceans linked to the global warming. My question is about a single strange sentence: It's written that "This rise of water is not uniform (all aroud Australia ) : on the south, the sea has risen at a speed of 3 mm per year during the recent years, but has risen at a speed of (from 7 to 10) mm per year on the north coast."

Question : How can the sea rise at a different speed on 2 shores opposite the same island ? (even if this island is a near-continent). With the difference between the 2 speeds (7-3)=4 mmm per year for 10 years long it makes 4 cm (more than 1 inch).

When I asked this question on the Reference desk in French for the 1rst time some months ago I got answers refering to earth gravity changes, but I think it's not conclusive. I also got answers sending me to Geoid but I also think that this geoid doesn't change enough to explain this strange difference between 2 "sea rise speeds".

Sorry for being so long asking my question, thank you very much for your "cogitations". Joël DESHAIES- Rheims-France---90.18.59.162 (talk) 14:07, 5 July 2010 (UTC)


 * Surprising as it may sound to you, the answers you were given are the correct ones. Dauto (talk) 14:38, 5 July 2010 (UTC)
 * The mistake you seem to be making is to look at the issue as a problem in hydrostatics, when the oceans are a dynamic system with continual energy input from the Sun. The height of a column of water depends on other factors apart from gravity, for example the temperature and the salinity. Just to give one well known example, the mean sea level (MSL) of the Pacific Ocean at that end of the Panama Canal is 20 cm (8 inches) higher than the MSL of the Atlantic Ocean just 77 km (48 miles) away. Physchim62 (talk) 15:42, 5 July 2010 (UTC)
 * Yes, there are 'anomalies' in sea level height, but how to explain the anomaly in the rate of sea level rise ?? 87.102.23.18 (talk) 16:28, 5 July 2010 (UTC)


 * Well, I think the question has a point. It is possible to have different sea level changes at different points, but it clearly isn't possible for the differences to build up continuously at a steady rate for very long.  And the explanation wouldn't be in terms of earth gravity changes, but more likely in terms of changes in wind patterns and ocean currents, which push the water from place to place.  As Psychim62 pointed out, there is a difference of 20 cm between the Atlantic and Pacific sea levels at Panama, caused by winds and currents. Looie496 (talk) 16:31, 5 July 2010 (UTC)
 * Perhaps the answer is related to average changes in wind/current direction then, happening at the same time as (and probably related to) the overal sea rise/warming effect. I don't know how to search for such data though.87.102.23.18 (talk) 16:40, 5 July 2010 (UTC)
 * The Australian tectonic plate moves North (causing seismic activity Java - Indonesia). Might this induce a N-S tilt in Australia? Cuddlyable3 (talk) 18:44, 5 July 2010 (UTC)

Hello, I'm the French OP. Indeed, my title is wrong using "hydrostatic", we have clearly to think in terms of hydrodynamic. As some of you pointed, the hard thing is not the difference of "altitudes" but the difference of "speeds" in rising. After reading your explainations and the French ones hear I'm still at the same point : or I don't understand how it can be possible, or (and it's my opinion now) there's a mistake in the data, according to me it just scientificly impossible. In anycase, I thank you all for helping me understanding sciences. Rheims - France ---90.18.59.162 (talk) 13:28, 6 July 2010 (UTC)


 * The important part is "in recent years". Obviously the difference can't continue forever, but by your own calculations, it can continue for 10 years without doing anything impossible. Looie496 (talk) 20:11, 6 July 2010 (UTC)


 * Sea level rise can indeed be higher in some areas than others. Tides, for example, can increase the sea level rise beyond its original levels, but melting of nearby ice caps and shifting of ocean currents can be another factor. A cold current being replaced with a warm current will increase sea level rise, but constant melting from glacial outlets (such as Jakobshavn Isbrae and Pine Island Bay can "channel" the extra water onto a specific swath of the ocean, see here for example. Also, variations in the El Nino Southern Oscillation already causes sea level variations on the scale of several feet between warm and cold anomalies off the coast of South America. Similarly, the drop in sea levels from the 1998 El Nino to the 2008 La Nina is just about enough to almost exactly cancel out the global sea level rise seen in Tuvalu in the same period. Thermal expansion will also be more siginifcant in Arctic regions, meaning the coasts of the Arctic Sea could have more sea level rise than in warm, tropical oceans. ~ A H  1 (TCU) 15:06, 7 July 2010 (UTC)


 * There's no reason to suspect a mistake in the data: I have a plot sitting in front of me (possibly from Kang et al., Inhomogeneous Sea Level Rise in the East/Japan Sea, JGR 110 (2005), but I can't find the paper online) that shows average sea level changes from 1992 to 2002 ranging from -4mm/yr to 16mm/yr in the Sea of Japan. Direct measurements and data from TOPEX/Poseidon agree with each other in this area. As others have said, changes in warm/cold currents and areas of upwelling/downwelling could cause this kind of discrepancy (and keep in mind changes of millimetres per year aren't large; static differences in sea level can be in the range of metres). 198.103.39.129 (talk) 18:23, 7 July 2010 (UTC)

Difference between mud and loam
What is the difference between mud and loam, please? I am interested mainly in their use as a construction material.

Wikipedia says that loam consists of sand, silt and clay and that mud consists of soil, silt and clay, but can also contain sand. Thus, to me not being a native speaker both terms seem to have the same meaning. --146.107.3.4 (talk) 14:11, 5 July 2010 (UTC)
 * In British English, "loam" is used to describe a type of soil (a type that often becomes "muddy" in the British climate): "mud" is a more general term. Physchim62 (talk) 14:31, 5 July 2010 (UTC)


 * (ec)In agriculture Mud generally refers to ground matter/earth/soil that is clay rich - (ie not really peat, topsoil, humus though they will be described as mud when very wet ). it is generally clay like in nature, but may be more liquid. Loam is generally more particulate, and so has better drainage.. though when wet it can be described as mud. It is not as slicky as clay.
 * In argricultural terms they are different. In building terms they are less distinct see http://www.thefreedictionary.com/loam : "A mixture of moist clay and sand" which is very similar to mud as used in Mudbrick.87.102.23.18 (talk) 14:38, 5 July 2010 (UTC)


 * You might find this useful http://www.tbe-euro.com/downloads/SustainableBuildingConference-Austria1.pdf : in construction terms I haven't found an example where the two can't be used fairly interchangably.87.102.23.18 (talk) 14:42, 5 July 2010 (UTC)


 * More Were you thinking of mudbricks and walls or more in terms of groundwork/subgrades? In terms of foundations etc this book makes some useful distinctions 87.102.23.18 (talk) 15:04, 5 July 2010 (UTC)

The difference is a matter of water content mainly. Mud always means soil that is saturated with water enough to be sticky and squishy. If it dries out, it isn't mud any more. Loam is simply a type of soil with no particular implication about water content. If you saturate loam with water, it turns to mud. Looie496 (talk) 16:20, 5 July 2010 (UTC)


 * Soil classification defines types of soils based on their sand, silt and clay content. Mud usually contains more water than loam. ~ A H  1 (TCU) 14:55, 7 July 2010 (UTC)

Is it Gun cotton?
This is what we found inside, besides shot itself, when we open a of 12 gauge shotgun cartridge in India. Is it so in the West ? I mean what exactly you find in yours in real life (as opposed to Wikipedia article)? What exactly is the stuff I have shown ? Is it gun cotton, or cordite what ever ? (the scale in centimeter) Jon Ascton    (talk)  17:24, 5 July 2010 (UTC)
 * I think it is either cordite, or, more likely, Smokeless powder. Guncotton isn't black. --The High Fin Sperm Whale 17:36, 5 July 2010 (UTC)


 * No, it ain't black either (only seems in pic).It is in fact dark green  Jon Ascton    (talk)  17:42, 5 July 2010 (UTC)


 * It's not pure gun-cotton nitrocellulose which is white like cotton. Nor cordite (image in article). It's almost certainly a form of smokeless powder. You might find this useful - the powder is similar but slightly lighter. If the cartidge was more full than those in the links with powder then they could be using real gunpowder which is less powerful.87.102.23.18 (talk) 17:53, 5 July 2010 (UTC)
 * You might find the cutaway shells here  interesting to look at.87.102.23.18 (talk) 18:05, 5 July 2010 (UTC)

In that case, I'd guess smokeless gunpowder (smokeless gunpowder has so many different formulas and ingredients, probably one of them is dark green, or it could even be coloured like that on purpose). --The High Fin Sperm Whale 17:56, 5 July 2010 (UTC)


 * Yes, this is exactly what I found. The link seems to say that such shot is only meant for bird game, i.e. not in serious ammunition ? What about the standard shotgun ammo in the west ? And what about pistol and revolver etc. ?  Jon Ascton    (talk)  18:26, 5 July 2010 (UTC)


 * And, the other question, actually I already asked it in another post - talking of novel uses of 12 gauge shotgun cartridge, is there any machine which exploits the rush of its blast to dig a hole in ground when you have no time for a shovel ?


 * Erm - shotguns are mostly for bird game, (or firing at rats etc) - the small amount of powder is due to it's high power - shotgun cartridges were originally made for gunpowder - see Shotgun_shell " Modern smokeless powders are far more efficient than the original black powder used in shotgun shells, so very little space is actually taken by powder" - even the ones for bigger game have a lot of wadding eg see Shotgun slug (image right).
 * Were you thinking about military use? 94.72.242.84 (talk) 18:40, 5 July 2010 (UTC)


 * For rifle or pistol cartridges I can't do better than this which has numerous cutaway diagrams of the 'shells'.94.72.242.84 (talk) 18:44, 5 July 2010 (UTC)

.--Stone (talk) 20:07, 5 July 2010 (UTC)


 * A Mythbusters episode tried to reproduce using a gun to cut a circular hole in a floor to escape from the bad guys. I recall that regular firearms were ineffective, and I imagine digging through dirt would be a lot harder. Besides, the dirt would be mostly pushed forward rather than to the side. Clarityfiend (talk) 02:06, 6 July 2010 (UTC)


 * Yeah - I think the most effective thing you could do to dig a hole with a shotgun shell would be to extract the explosive charge and push it as deep into the soil as you could and then set it off with a fuze. The resulting crater would be the best result you could possibly hope.  The energy from the charge would mostly be directed upwards - towards pushing dirt out of the hole - although in soft soil, maybe half of the energy would go to compressing the soil beneath and making it harder to dig the next bit out.  But the 'crater' made from a single shotgun shell would be unlikely to be more than a couple of handfuls of dirt...barely one shovel-full, I'd expect.  There just isn't that much energy there.  People do use small amounts of explosives to break up large rocks while excavating - but the solidity of a rock makes it much more amenable to breaking by explosives than soft, flexible, compressible soil.  Furthermore, the goal is generally to break the rock into manageable chunks - not to physically remove it from the hole, which is energetically much more challenging. SteveBaker (talk) 13:30, 6 July 2010 (UTC)
 * Check out nuclear demolition. There were several plans to blast instant harbours and canals using atom bombs, and the Soviet Union is thought to have actually used bombs to stop gas well fires. Cod Lover Oil (talk) 16:34, 6 July 2010 (UTC)
 * Yes but there is a tad more energy involved with a nuclear bomb than a shotgun shell. Obviously you can do excavation with explosives - mines and quarries do exactly that all the time.  But the puny amount of explosive in a shotgun shell just isn't enough to make much of a hole...even less so if you use that explosive to drive things into the ground rather than lifting stuff out of the hole. SteveBaker (talk) 19:46, 6 July 2010 (UTC)
 * Bunker buster is kinda, sorta close to the concept, although it's job isn't to dig, either. The accompanying image does show some uplift, but I think almost all of it goes back down in roughly the same spot. Maybe Nuclear bunker buster is even closer. These would work better on asteroids, where the gravity is lower. -- JohnWBarber (talk) 00:01, 7 July 2010 (UTC)

Duty or pleasure?
I remember reading in my beginner level Biology books that living things should be able to reproduce. I used to think that all organisms had a sort of 'obligation' to reproduce and hence propagate their species. My current view is that almost all animals copulate due to attraction to the opposite sex and the resulting offspring are not on the parents minds during courtship. Is this natures way of ensuring that species propagate and do not go extinct by hiding duty behind pleasure? Thanks. --119.155.112.195 (talk) 20:08, 5 July 2010 (UTC)


 * Propagation of Life is the foremost project of evolution, nothing is more important, natural selection is a by-product of the process. Therefore the biological apparatus is designed in such a way that greatest pleasure (enjoyment of sex) can only be achieved by engaging in the process of intercourse. You see, it is a sort of bribe Evolution offers us so that can make the nature work ! By "we" I mean we all, that includes all other species. Interestingly Homo sapiens are the only organisms that can "cheat" mother nature i.e. family planning that is we can have sex for enjoyment alone, I think that Evolutionary Forces will now find some round about to overcome this danger ! Jon Ascton    (talk)  20:30, 5 July 2010 (UTC)


 * You'd love Idiocracy --mboverload @ 21:45, 5 July 2010 (UTC)


 * "Almost all animals" is probably too strong. There seems to be a neural "reward" system in all vertebrates, and I believe it is activated by sexual activity in all vertebrates that have been examined. There is also a reward system in insects, but I don't know if it is activated by sex. I don't think there is much information about other types of invertebrates such as molluscs and worms. In any case, there is no requirement for pleasure to be associated with reproduction -- it is theoretically possible for organisms to be hard-wired to give the necessary responses to the appropriate stimuli, without pleasure coming into the picture. Looie496 (talk) 21:30, 5 July 2010 (UTC)


 * Of course, that's what I meant in other words, in a scientists words (yours) it may sound a bit different, but believe me we are saying the same thing - "pleasure" is a human term," hard-wired to give the necessary responses to the appropriate stimuli" is what I meant if I were you. Perhaps I should not use the word "pleasure"... Jon Ascton    (talk)


 * I probably didn't explain clearly enough. To say that an animal does something for pleasure means that it is capable of anticipating the consequences of actions, estimating the pleasure expected from each, and choosing the one that is expected to yield the greatest pleasure.  Those are sophisticated capabilities, probably beyond the reach of many species.  The simplest alternative is to have direct, mechanical connections from certain sensory detectors to certain motor systems, so that detection of the presence of a possible mate leads automatically to performance of the response.  I think it would be more reasonable to describe that sort of system as "duty" than as "pleasure" (although neither term is totally accurate). Looie496 (talk) 04:16, 6 July 2010 (UTC)


 * Both assign too much conscious agency. The essential point is that the evolutionary process leads to drives for reproduction—and if it didn't in some species, they would eventually die out. The mechanisms of those specific drives are not a conscious will to reproduce, even in human beings. Humans are sort of a special case because our understanding of reproductive biology and social consequences are probably much higher than any other animals, and we have rich cultures of reproduction. But our basic drive for sexual intercourse is not motivated by a conscious desire to have babies—it's the other way around. Our gonads say, "do stuff," and we do it, and end up with babies as a result. We see the connection. I'm not sure other animals do. "Pleasure" is probably a better term than "duty" for lots of animals, but "duty" is a bad term even for bugs, who do it not because they feel consciously required to, but because they are programmed to do it. --Mr.98 (talk) 13:03, 6 July 2010 (UTC)


 * I think you're looking at it backwards. I forget who originally said it - but the truth is that an animal is just a gene's way of making another gene.


 * From the perspective of a gene, it has to make an animal (or a plant or whatever) that has the highest probability of successfully preserving the gene into the future and spreading as many copies of it as possible. The whole business of animals and plants and mating and all of that stuff is just the way that the gene has found (by evolution) to be most effective in performing that task.  The gene had to evolve to make sex pleasurable - or to provide some other 'drive' to do it because that's an effective strategy for ensuring that it'll get propagated.


 * But this strategy is complicated. If we (as the intermediaries 'caused' by the genes) don't feel an obligation to have kids - if we decide to use birth control through our fertile years...or to become homosexual or to simply abstain from sex altogether - then the gene has failed in it's task to provide that 'sex drive' and will (by definition) be eliminated from the next generation.  The gene failed.  Do we care that the gene failed?  Maybe not.  We only care if our genes gave us brains that made us care!


 * It goes beyond the actual act of creating a child too. If we were genetically 'wired' to have a baby and then abandon it - then those genes would also die out after just one generation.  So having kids can be fun - it's definitely rewarding to see your son or daughter go to college and be a success.  But the reason why that's a pleasure is because it was to the gene's advantage to have us continue to promote the continued existence of the next generation to the point where it too could propagate the next generation.  Why are grandparents suddenly so fixated on their grandchildren?  Guess what?  Once their child has produced offspring, the most necessary thing for the continued propagation of those genes is to protect the grandchildren - and to hell with the intervening generation!


 * Hence, the process of evolution has molded the gene to the point where it produces human brains that have instinctual goals to produce offspring and to protect and educate them appropriately.


 * SteveBaker (talk) 13:20, 6 July 2010 (UTC)
 * I think your thinking of the Gene-centered view of evolution most notable expressed by Richard Dawkins in The Selfish Gene who I think was the one to coin the phrase ;a whatever is just a gene's way of making another gene'. Nil Einne (talk) 00:02, 7 July 2010 (UTC)
 * Aha! Thank-you! I was half-suspecting it was Dawkins, but I couldn't remember the precise wording of it so I couldn't search for it and I was side-tracked by wondering if it was Desmond Morris who first said it.  Well, whatever.  It's an interesting (and entirely valid) way to view the world. SteveBaker (talk) 05:24, 7 July 2010 (UTC)

'Hence, the process of evolution has molded the gene to the point where it produces human brains that have instinctual goals to produce offspring and to protect and educate them appropriately.'

Is it the genes that make a human parent want to send his child to school or the modern norm of good education = good job = respect that has changed the way people think about education? --119.155.11.103 (talk) 15:34, 6 July 2010 (UTC)


 * Yes, I think so. We have a general, instinctive (and therefore, genetic) drive to want the best for our children.  That drive is filtered through intelligence, learned behavior, logic, economics, etc - but in the end, the reason we send our kids to school is that we are instinctually driven to have them perpetuate our genes.  Of course, we're using our brains to actively consider how to turn that general 'drive' into actions: "Will sending my kid to school result in him/her getting a better job?"...and..."Will having a better job result in my kids not being hungry, having a roof over their heads?"...those are conscious thoughts - but deep down, it's probably genetics giving us the general drive to want our kids to do well.  It's the same with sex, while we only have a rather general drive to reproduce, the precise details of whether to take the girl to the dance or to the movies and whether candy or flowers would make the best impression are coming from our intelligence because we haven't had time to evolve to believe that owning a red convertible with turbochargers and wide tyres will definitely get us laid.  (Hmmm - I think I may have just disproven something! :-)


 * Without genetics, this is a crazily strong drive. Almost all parents would truthfully say that if it came down to it, they would happily lay down their lives to save their kids...and there are plenty of cases where parents have done exactly that.  That's an amazing thing - there is really no other instinct that so completely overrides our goal of self-preservation.  If not for the pressure of our genes trying to be perpetuated, why on earth would we do that?


 * The genes provide the "Why" and our intelligence provides the "How".


 * SteveBaker (talk) 19:34, 6 July 2010 (UTC)


 * Steve, I agree with all that you say, but I am also puzzled by the fact that some people - including myself and a number of my personal acquaintances (mostly male) - have never felt any desire whatever to have children (as opposed to just having recreational sex should the opportunity arise) and indeed have always actively disliked the idea. Do you think these are examples of individual 'nurture' overriding (genetic) 'nature', or do you know of a genetic explanation that might account for it. (NB: this is not merely a reflection of physical immaturity, as I'm in my 50s!) 87.81.230.195 (talk) 21:36, 6 July 2010 (UTC)


 * It's complicated (warning: I have an anthropology degree). In very general terms, evolutionary pressures have shaped our desires so as to best leave more of our DNA in the gene pool. It's important for us to eat, drink, pass waste, exercise, and have sex, so these things all make us feel good in various ways. By virtue of their biology, female mammals are much more likely to be responsible for raising the children than the males are - and women are no exception to that rule. But raising kids is no mean feat; it takes a lot of time and energy to carry a baby to term and it then takes even more time and energy to raise the kid enough for them to strike out on their own. That kind of drawn out task is hard to reward with a bribe (like an orgasm); it's rewarding, but nobody has kids so that twenty years later they can look back on the sweat and toil with satisfaction! What's needed instead is a brain that's hard-wired to want to raise kids; it's no accident that young girls play house and put diapers on their teddy bears; their brains are wired to make them instinctively want to do that. They therefore find that kind of play rewarding and are more likely to plunge into the sacrifices needed for the real thing. Men have different drives. We could, in theory, simply enjoy our orgasms with every woman in the area and not think at all about wanting to have a child. If you wanted to look at it cynically, I guess you could say it's because women are forced to care for the child anyway. However you equate it, men can get away with contributing less to the child-rearing, so their brains are not wired in the same way as to find such stuff enjoyable. I'm not saying it's fair, I'm just saying that's how the balance sheet works out. The first complication is that men who have children and stay with the family unit can form extremely strong bonds to their kids. Even men (such as myself) who had little desire for children before parenthood find that switch suddenly turned on. Which makes evolutionary sense as well, of course; children of parents who both care for them have a survival advantage against those that must make do with one parent. This is in contrast to the so-called Cinderella effect, which involves some grim aspects of children being raised by step-parents (see here as well). The most over-arching complication of course, is that people are all individuals and while it's easy to talk in generalizations, specifics will always be cloudy. When I first became a dad, I had no idea I would become a devoted parent, for example; there are an unfortunate number of parents (or either sex) who do not. And not every girl plays with dolls and not every woman has the strong basic urge to "listen to their biological clock". But in general they do; those stereotypes didn't just come out of the blue, they illustrate some of the ways natural selection has worked to shape our desires. Some of this comes from my understanding of parenthood as I've experienced it in, some of it comes from my degree, but it's not entirely OR. You may find the works of Helen Fisher and Desmond Morris to be of interest, for example. Our article on Sexual selection in human evolution also touches on some of this. Matt Deres (talk) 23:19, 6 July 2010 (UTC)
 * It's worth pointing out that everyone who decides not to have kids, and sticks with that decision, has essentially extinguished his particular genetics, while those who do want kids and are able to have them will pass their genetics along. And since there is no shortage of kids in the world, everybody's happy. ←Baseball Bugs What's up, Doc? carrots→ 23:36, 6 July 2010 (UTC)


 * Seen from the perspective of the gene, those people who choose not to (or fail to) have healthy, long-lived children have failed in the one single thing that the gene is "trying" to make them do (it's hard not to anthopomorphize!). And from the perspective of the genes of people who do have offspring, it's absolutely wonderful that some people choose not to do that because it leaves more potential mates and more resources for the offspring of those who do...which is a huge win!  But I agree - why do we (as humans) have to satisfy our genes?  If they fail to compel (or at least sufficiently encourage) us to do what they "need" then it's no big deal so long as we don't somehow suffer as a consequence.  In times of old, not having children meant not having anyone to look after you in old age - which would have been a really serious problem for subsistance farmers and hunter-gatherers - but in modern society, we can avoid that issue fairly easily by saving money, buying into pension plans, creating systems of government with welfare, and so forth.  In a very real sense, we've managed to cheat our genetics.  Evolutionary theory says that sooner or later, the genes will catch on and adapt some clever new strategy...maybe in a few generations, some weird genetic flook will pop up and cause us to gradually suffer more and more horrible pain if we don't have a kid by age 30!  Such a mutation would have significantly more breeding success than the lackadaisical gene that let's us get away without reproducing - and would therefore spread rapidly throughout the population, to the general detriment and misery of us humans. SteveBaker (talk) 05:13, 7 July 2010 (UTC)

Identifying a Howitzer
Greetings,

I am trying to identify a howitzer. The photographs were taken at the entrance of the fort of Ouvrage Saint-Gobain; I was told that it is a Skoda 105mm, but I have doubts.

Thank you very much in advance! Rama (talk) 21:23, 5 July 2010 (UTC)
 * Commons has a couple of pictures of a 105mm howitzer in the Skoda artillery category -- you can compare them. Looie496 (talk) 21:43, 5 July 2010 (UTC)