Wikipedia:Reference desk/Archives/Science/2016 July 30

= July 30 =

Perceptions of suicide
Suicide is often viewed either as a selfish act or an act of desperation, and hence not selfish, but ultimately does it not depend on the circumstance and the perspective you look at it from? Why are the general views one or the other? 2A02:C7D:B99F:5300:CAF:A38B:AC61:C4F7 (talk) 12:31, 30 July 2016 (UTC)


 * Death_and_culture and Philosophy of suicide have something about this.Hofhof (talk) 13:11, 30 July 2016 (UTC)


 * In some cultures suicide is seen as honorable, perhaps as the only honorable option, in some cases. Also, even in cultures where suicide is not seen that way, in cases where death is certain in short order anyway, it is more acceptable.  Two such cases are terminal disease and facing capture by an enemy that is certain to torture and kill them. StuRat (talk) 18:28, 30 July 2016 (UTC)

Code of ethics that psychotherapists are supposed to follow
Are psychotherapists allowed to go with patients for a walk during talk therapy? Could they meet over lunch or coffee for a therapy session outside the psychologist office? — Preceding unsigned comment added by Hofhof (talk • contribs) 14:28, 30 July 2016 (UTC)
 * Different countries, different rules. The main principle seems to be confidentiality - so a walk might be fine but a cafe could present problems. Wymspen (talk) 15:05, 30 July 2016 (UTC)
 * Sure, the laws and regulations could deal with this in a complete different way around the globe. But I am interested in the scientific part of this. Besides your point, I was asking also while it could imply crossing the line between professional space and private space. That is, mixing two types of roles in the relationship. --Hofhof (talk) 17:28, 30 July 2016 (UTC)
 * In you'll see the FBI believe they have the right to put bugs anywhere in public spaces without needing special permission and without specially targeting criminals. So yes I'd have thought they should have a reasonable expectation of privacy but that is not what the government thinks. Dmcq (talk) 17:44, 30 July 2016 (UTC)

Do the same areas of a man's brain light up when his nipples are stimulated in comparison to when his genitals are stimulated?
After all, I know that the same areas of a woman's brain light up when her nipples are stimulated and when her genitals are stimulated. Thus, I am wondering if this is also true for men. Futurist110 (talk) 19:21, 30 July 2016 (UTC)
 * Your premise is in fact based on a false assumption. When different parts of the body are stimulated by tactile contact, they in fact trigger distinct patterns of firing in the somatosensory regions of the brain.  Now it may be true that in a given individual, on a given occasion, that this may result in similar responses in other regions of the brain that control a wide variety of other physiological and biopsychological responses, from arousal, to relaxation, to alarm.  Then again, they easily may not (and they will certainly never approach being truly identical).  But any similarity will vary by individual, by occasion, by state of consciousness, by mood, by pretty much any other mental or physical factor or circumstance.  So there is no real concrete, plausible, general answer to your question, because the premise is just too fundamentally flawed.  Now, if you're asking if some men are aroused by having their nipples stimulated, the answer is unequivocally yes.  But surely that does not come as a surprise to you?  S n o w  let's rap 07:53, 31 July 2016 (UTC)

Sahara desert
How long did it take for the non-oasis soil to disappear after the climate became desertic? Sagittarian Milky Way (talk) 21:00, 30 July 2016 (UTC)
 * Just a point in the right direction as I don't have the time to follow up the primary sources tonight, but I would check out the sources for Chapter 19 (How Africa became Black) of Jared Diamond's Guns, Germs and Steel. I think you should be able to find "further readings" section online; if not, I will transcribe them here for you tomorrow. Numerous of these sources are clearly concerned with the ecological state of the region during the relevant period, so I suspect the answer to your question can be found in one of them! Good luck!  S n o w  let's rap 08:04, 31 July 2016 (UTC)


 * Based on the Dust Bowl, not long. Mikenorton (talk) 09:31, 31 July 2016 (UTC)


 * It isn't the Sahara, but you can look at Needles, CA as an example. Look at a satellite map. It takes about 3 years for a farm to turn completely back into sand. You will see farms, sandy farms, and areas that should have farms based on the surrounding land, but are just sand. Obviously, the soil does not just walk away. It is more likely that it gets buried under the sand. 209.149.113.4 (talk) 19:20, 1 August 2016 (UTC)


 * Fertile soil *can* disappear by a) blowing away (cf Dust Bowl above) and b) soil erosion, exacerbated by farming practices and unusually high rainfall washing dirt into rivers. Carbon Caryatid (talk) 11:36, 2 August 2016 (UTC)


 * Also, dehydrated soil can be rather similar to sand. The organic portion that makes it black dries up and blows away or washes away, leaving just the mineral content, which is more like dust, or, if high in clay, more like dried mud, than soil. StuRat (talk) 20:28, 2 August 2016 (UTC)

Estimating the weight of a dinosaur from its footprint
Is it possible to get an estimate of the weight of this dinosaur using the depth of the footprint, e.g. using the indentation of some small stones or by estimating the softness of the ground the dinosaur was standing on using other means? Count Iblis (talk) 21:21, 30 July 2016 (UTC)


 * Working out the softness of the ground is the biggest problem I think. This study of producing dinosaur tracks experimentally says "It is impossible to achieve a quantitative test for all fossil dinosaur tracks as there are too many variables to account for. These variables include the moisture content at the time of track formation, the weight of the dinosaur, the true morphology of the dinosaur's foot, and the exact gait of the dinosaur at the time of track formation". Note also that many tracks were left by dinosaurs moving through various depths of shallow water, which may have part-supported their weight. Another factor is that the track may be preserved in a layer that was not actually at the surface at the time, but was below another more easily erodible layer now gone. To sum up, too many variables. Mikenorton (talk) 09:39, 31 July 2016 (UTC)


 * Thanks! Count Iblis (talk) 00:02, 2 August 2016 (UTC)


 * However, it is possible to estimate the weight of a dinosaur by everything else about the footprint. The shape/form would let them know what type of dinosaur it is, and then they would use the size of the print (width and length) to figure out what size individual they had.  Knowing the species and the size would give a good estimate as to the weight.  Exceptions would be if the print was from an unknown species or so poor that the species and/or size could not be determined. StuRat (talk) 20:32, 2 August 2016 (UTC)