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April 6

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Electric bath warmer

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Would warming a bath with this product actually work and would it be safe? How long might it take to warm an 80L bath to 40c? 108.192.136.193 (talk) 00:34, 6 April 2015 (UTC)[reply]

Note: The image linked shows an immersion heater. -- ToE 09:32, 6 April 2015 (UTC)[reply]
We are in no position to answer questions regarding electrical safety based on nothing but a photograph - though I very much doubt that such a device would be compatible with electrical safety regulations in most countries if used in such manner. Even ignoring the obvious risks of electrocution, anything that small capable of heating a bath full of water is going to present a significant risk of burns. In short, we can't answer your question, and even if we could, the only answer we could legitimately give is "don't even think about trying it". AndyTheGrump (talk) 03:41, 6 April 2015 (UTC)[reply]
With the caveats mentioned by AndyTheGrump above, my guess would be that, in a cold room, the bath of water would lose heat faster than that device could add it, so it would never reach 40C. In the distant past, I have heated a bath with a higher power immersion heater, and it worked, but it was a very dangerous thing to do and I now have more sense (I think). Dbfirs 07:20, 6 April 2015 (UTC)[reply]
Those are designed for heating a cup of cold water to about 80-90°C (175-195°F) for coffee/tea etc. Assuming no losses for all these calculations, we get: To heat 300 millilitres (10 US fl oz) from 10°C to 90°C requires about 100kJ of energy, to do so in 1 minute requires 1.7kW of power. To heat 50litres (about half a bathfull, before you get in( of water by 30°C (from 10°C to 40°C) requires 6,300kJ. At 1.7kW, that's just over 1 hour, so even without any losses to the air, it's impracticable. LongHairedFop (talk) 08:32, 6 April 2015 (UTC)[reply]
I doubt it's actually as high as 1.7kW. This one, for example, is just 300W.--Phil Holmes (talk) 12:06, 6 April 2015 (UTC)[reply]
Yes, 1 minute sounds very fast to boil a cup of water, I believe a powerful microwave can do it in about a minute, but I wouldn't be surprised if one of those old immersion heaters took 3 or 4 miunutes to boil a cup.Vespine (talk) 00:19, 7 April 2015 (UTC)[reply]
I've never used one, so the time of 1 minute was picked at semi-random. The one in Electric_heating#Immersion_heater is indicated at 500W. Anyway, a 300W unit will take about 3hrs to heat a bath, assuming no losses. — Preceding unsigned comment added by 62.56.48.4 (talk) 09:31, 7 April 2015 (UTC)[reply]

regrowing fingers

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How come my skin regrows when it gets cut and my bones regrow when they break, but my chopped off finger won't grow back? — Preceding unsigned comment added by 219.137.229.2 (talk) 00:56, 6 April 2015 (UTC)[reply]

Wikipedia has an article titled Regeneration in humans. I suggest you read that article, and then read any bluelinks from that article, to see where it takes you in your research. --Jayron32 01:00, 6 April 2015 (UTC)[reply]

That's a bit beyond my mental abilities. Can you just tell me? Thanks! — Preceding unsigned comment added by 219.137.229.2 (talk) 01:06, 6 April 2015 (UTC)[reply]

Healing vs. regeneration. Different processes. ←Baseball Bugs What's up, Doc? carrots02:46, 6 April 2015 (UTC)[reply]

From what I found it appears that there really is not an answer to this question as of yet. There have actually been documented cases in an article from nature.com [1] it is documented that some children have been known to regrow fingertips and some adults have even grown back parts of their liver. We have the ability when we are in the womb, humans are built piece by piece simply because we have stem cells by the time we are born our cells turn into adult somatic cells. Other animals still have stem cells even in adulthood [2]. According to NUI-Galway’s Frank's research there may be two main reasons of human's lack of regenerative abilities. First if an amphibian loses a limb it can hide and regenerate without the need for food, this is simply not an option for a mammal with a fast metabolism that must eat, thus a mammal must regenerate "quick, and dirtily" [3]. Professor Galway states “Because these (embryonic-like stem) cells are so versatile, it is difficult to keep them under control,” Frank explains. “They are more likely to ‘misbehave' or form tumors than differentiated cells. We hypothesize that only animals that have very simple body plans, like Hydractinia, can manage this problem because they have less complex organs and 'misbehaving' cells are less of a problem. But complex animals, like humans, need better control of their cells to maintain their highly complex organs. They have to get rid of them during early development before they become too complex.”[4]) Lriverauk22 (talk) 03:40, 6 April 2015 (UTC)[reply]

References

Note that an injury can be completely healed if the wound is small. That is, new skin or bone can be grown. However, if the injury is larger, then you get scar tissue instead, which isn't as good (less flexible, for one thing), but seems to be necessary to plug the wound quickly, to avoid infection in the case of skin, or allow the use of the leg in the case of a broken femur, etc. In the womb there's little risk of infection and the bones don't need to be used, so there's plenty of time to grow new body parts. Not so on the outside. (The obvious solution would be to use scar tissue to quickly plug the wound, then slowly replace the scar tissue with new skin, bone, etc., but evolution doesn't seem to have figured out how to do that yet.) StuRat (talk) 06:19, 6 April 2015 (UTC)[reply]
That sort of language is very misleading - evolution doesn't "figure anything out". It is a simple process of selection where random changes that confer an advantage for survival are passed on and those that don't confer an advantage tend to die out. Richerman (talk) 09:47, 6 April 2015 (UTC)[reply]
Yes, I was obviously anthropomorphising it, for comic effect. StuRat (talk) 20:50, 6 April 2015 (UTC) [reply]
Evolution does "figure things out" in a way. It's just that it's via non-conscious trial and error. Or as the saying goes, "Nature finds a way." ←Baseball Bugs What's up, Doc? carrots22:09, 6 April 2015 (UTC)[reply]

Turning into a skeleton

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After a person is buried in a coffin how long does it take for them to turn into a skeleton? 212.47.240.157 (talk) 03:18, 6 April 2015 (UTC)[reply]

After being buried 6 feet underground it takes about 10-15 years according to two of three sources I found with one source saying it could take up to 50 years but that is an extreme outlier and it highly depends on what the coffin is made out of. The 50 year process is common in those that are made out of solid oak.

Here are links to sourcing for this answer. http://www.enkicharity.com/how-long-does-it-take-for-a-body-to-decompose.html http://www.theguardian.com/lifeandstyle/2008/feb/16/healthandwellbeing.weekend2 http://www.memorialpages.co.uk/articles/decomposition.php — Preceding unsigned comment added by Trivle (talkcontribs) 03:47, 6 April 2015 (UTC) Trivle (talk) 03:53, 6 April 2015 (UTC)[reply]

Depends on the pH of the soil that the coffin is buried in. Sarcophagus means "flesh-eating"'. Being alkali, the flesh decomposes very quickly. In acid conditions (such as Bog Bodies) the flesh can last millennia. My mother-in-law has pickled herself in gin and tonic and martinis so still looks 21 (cough, cough)--Aspro (talk) 21:48, 6 April 2015 (UTC)[reply]
I wish I could tell you how old that joke is. :) Now, these questions are about below-ground burials. Wouldn't the concrete vault stave off that process? Also, wouldn't an above-ground crypt also stave off that process? I recall they disinterred Zach Taylor's body a few years back, and even after 100 years they were able to do something resembling an autopsy. ←Baseball Bugs What's up, Doc? carrots22:07, 6 April 2015 (UTC)[reply]
Only the OP knows this but I take his question as to being buried in soil rather than being interned in a crypt or catacomb etc., were other conditions can exist, such as humidity/temperature and lead-lined/butyl rubber lined/wooden/stone/steel, etc., coffins maybe used. --Aspro (talk) 14:26, 7 April 2015 (UTC)[reply]

Our article about Incorruptibility may be of interest. Richerman (talk) 23:57, 6 April 2015 (UTC)[reply]

I realise that this is several days old but more than 134 years in the case of John Torrington. CambridgeBayWeather, Uqaqtuq (talk), Sunasuttuq 12:57, 8 April 2015 (UTC)[reply]

"Physicist's guide to life" book?

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I'm trying to recall a very good book I read a few years ago by a physicist who seemed to have a very good head on his or her shoulders and a great sense of humour. There were chapters on different themes; I think one might have been about nuclear power and another was definitely about nutrition. Some advice I remember in the nutrition chapter was something like "the best physical exercise for losing weight is pushing food away from yourself at the table". Please, what was this book? I hope somebody recognizes it. Hayttom 04:26, 6 April 2015 (UTC) — Preceding unsigned comment added by Hayttom (talkcontribs) [reply]

Did I do something wrong? My question seems to have landed in the middle of the previous answer. Hayttom 04:30, 6 April 2015 (UTC) — Preceding unsigned comment added by Hayttom (talkcontribs) [reply]
  • The error wasn't yours, it was Lriverauk22's when responding to the #regrowing fingers question. Auk added a number of references using <ref> tags, the same way they might do in an article. But by itself this would produce reference footnotes at the bottom of the whole page (I believe the RD pages are set up to do that; otherwise the footnotes might go nowhere). So each time a new question section was added (including yours), the references got separated farther and farther from the section they belonged to. On the RD and similar talk pages, if you use <ref>, you also need to add {{reflist-talk}} (or {{reflist}}, for a different format) below your contribution, so the reference footnotes stay inside the section. See Template:reflist-talk. It was Dismas who saw what had happened and added the missing template, moving the footnotes up where they belong. Thanks, Dismas. --65.95.176.148 (talk) 18:19, 6 April 2015 (UTC)[reply]
Do any of these ring a bell [1]? I believe Physics for Future Presidents includes both nuclear power and dieting, though I don't know if it matches your themes exactly. Dragons flight (talk) 05:58, 6 April 2015 (UTC)[reply]
That was quick ... yes, thanks, it was "Physics for Future Presidents: The Science Behind the Headlines". Hayttom 11:30, 6 April 2015 (UTC)[reply]
Our links: Physics for Future Presidents by Richard A. Muller -- ToE 18:40, 6 April 2015 (UTC)[reply]
Maybe something by Richard Feynman. Richard Avery (talk) 07:07, 6 April 2015 (UTC)[reply]
Resolved

sleep deprivation

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It is stated that sleep deprivation leads to madness and eventually death. However coma patients survive sometimes years in the coma but not sleeping. Can you explain? — Preceding unsigned comment added by KrikvsPicard1969 (talkcontribs) 11:34, 6 April 2015 (UTC)[reply]

Have you read Coma? ←Baseball Bugs What's up, Doc? carrots11:59, 6 April 2015 (UTC)[reply]
Are you saying that sleeping and comas are basically the same thing except that coma patients don't wake up in the morning? KrikvsPicard1969 (talk) 12:03, 6 April 2015 (UTC)[reply]
It's a different type of sleep, as noted in the article. What you're thinking about is being forced to stay awake, as a form of torture; or in the extreme case, the inability to fall asleep at all, which is called familial fatal insomnia. ←Baseball Bugs What's up, Doc? carrots12:19, 6 April 2015 (UTC)[reply]
  • Let me summarize -- the following information is in the coma article but might be hard to extract. The word "coma" is widely misused in the popular literature to encompass two distinct states, which doctors call (1) true coma, and (2) persistent vegetative states. Patients never survive for years in a state of true coma -- rarely longer than a few weeks, after which the patient either deteriorates or else progresses to a vegetative state. A patient in a vegetative state can survive for years. In true coma there is no genuine sleep, but in a vegetative state sleep-wake cycles are usually present. Bottom line: those patients who survive for years are not in a coma, they are in a vegetative state, and they do generally have sleep cycles. Looie496 (talk) 18:04, 6 April 2015 (UTC)[reply]
  • It's worth noting that insomnia does not, in itself, usually result in death, outside of a handful of isolated and poorly-understood cases concerning the condition which bugs linked to. That's not to say that persistent insomnia is in any way pleasant; after even a single day without sleep, cognitive function takes a dive and after a few days you're looking at serious neurological impairment affecting everything from hormone balance to social capability. Before a week, the physical and cognitive state is not far removed from catatonia. But even at its worst, insomnia is unlikely to result in death, unless it compounds upon another issue (say hypertension or heart disease). Those who are said (in the relevant scientific literature) to have died from insomnia belong to just a handful of families who have been afflicted with the (and the wording is ironic but appropriate) nightmarish genetic condition FFI, and have had little or no sleep for years on end before their bodies finally collapse under the strain. This documentary may be of interest to you. Snow let's rap 23:41, 6 April 2015 (UTC)[reply]

Losing weight

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If a person eats less and then feels hungry, is that the optimum time to begin exercise as the body is forced to draw upon fat stores rather than food in the belly? — Preceding unsigned comment added by 212.231.208.217 (talk) 17:01, 6 April 2015 (UTC)[reply]

Not necessarily. The truth is, you're likely to get a huge variety of answers to this inquiry, as this has long been an area of some controversy in the areas of nutrition and exercise physiology, with perspectives all over the place. While it's true that the exerciser's body will need to secure that energy from somewhere in its metabolic stores, it will not necessarily tap adipose tissue in order to do so, so the net effect upon both overall weight and the maintenance of muscle tissue (which might otherwise itself help keep down weight) could be poor. Again, advice is all over the place on this issue, but the most common perspective is to eat a typical meal about an hour before exercise and then a light snack shortly after; if one is looking to maintain their current weight the amount eaten should be roughly equivalent to that burned; if weight loss is the goal, slightly less should be eaten, but one should typically not go hungry into an intensive workout routine. Needless to say, if you personally are considering a new nutritional/exercise regimen, a consult with a physician is invaluable and (if you're inclined) they can always direct you towards a dietician or other nutritional expert. ([2], [3], [4], [5], [6], [7]) Snow let's rap 00:04, 7 April 2015 (UTC)[reply]
Weight = energy in vs energy out, it's actually not much more complex than that, despite the million self help and diet books that will try to convince you otherwise. The food in your stomach didn't magically 'disappear' becuase you didn't burn it up with exercise at the time. Put another way, if you exercise with food in your stomach, you won't be using up some portion of energy that you would otherwise 'poo' out or something if you didn't "use" it. The enegy from the food you ate will get used, whether you exercise or not, if you exercise you might burn more of it up, if you don't you'll store it, then you'll burn it later. Having said that, I do believe the general recommendation is to eat after exercise not before, but that's as much a practical consideration: exercising on a full stomach is not so comfortable and exercising does make you hungry so it makes sense to eat afterwards. Vespine (talk) 00:13, 7 April 2015 (UTC)[reply]
Of course, all of this is relative to general context. Obviously performance athletes and their support teams approach bio-energetics in a much more structured fashion, timing for exact amounts of macronutrients for very specific times, relative to exercise (and correspondingly, exercise timed relative to the metabolic cycle). Snow let's rap 02:26, 7 April 2015 (UTC)[reply]
The "energy in minus energy out = weight gain" is only going to be useful when you are way too heavy, say you weigh 110 kg while you should weight 75 kg. In that case, you should practice calorie restriction. Some exercise is then also recommended, but if you are that obese you are not physically fit enough to do strenous exercise. Exercise when you are not physically fit isn't going to burn a lot of calories, but being active like walking around will contribute quite a lot as you can keep that up for many hours. Simply walking around will burn 60 Kcal per hour more compared to sitting. So, if you do that for ten hours per day (take a standing desk instead of a normal one) you'll burn 600 Kcal more which is quite significant.
It's a totally different story if you your problem is that you weigh, say 82 kg while you want to weigh 75 kg and you notice that you do lose weight when you diet but when you are at your desired weight you tend to gain weight. In that case, the emphasis should not be on the diet but on physical fitness. You should gradually increase the exercise intensity, duration and frequency which will have the effect of increasing your basal metabolic rate. And this means that you should actually increase your calorie intake as you become fitter and are exercising harder. You must then make sure that your diet only contains healthy foods. If you were to diet and restrict calories then that would make it more difficult for your muscles to grow larger. The goal now is to have a steady state situation where you burn more calories at the same weight, which means that you must also eat more calories. You should do a combination of cardio and strength training, you could follow a program like this one. Count Iblis (talk) 05:29, 7 April 2015 (UTC)[reply]
The "energy in minus energy out = weight gain" is only going to be useful when you are way too heavy. I disagree, I don't see any reason why that would be the case. It's simply conservation of mass. One thing many people find surprising is that when you "lose weight" you aren't "converting fat into enerty", or digesting it and pooping it out, you are actually EXHALING it. The majority of weight is lost out of your front hole via carbon dioxide, not your back hole :). When you eat, energy goes in, when you exercise energy comes out: if more energy goes in you will gain weight, if more energy comes out you will lose weight, if they are roughly equal you will stay the same weight. It's really NOT much more complicated than that. Vespine (talk) 23:56, 7 April 2015 (UTC)[reply]
Agreed. Conservation of mass / energy is basically the only factor ultimately affecting weight. However, it isn't the only factor affecting overall health. Compared to a sedentary lifestyle, regular exercise will generally improve fitness and overall health regardless of weight. That's one reason to prefer a combination of diet and exercise in most recommendations for improving overall health. Dragons flight (talk) 00:29, 8 April 2015 (UTC)[reply]
Thing is that the basal metabolic rate is regulated by hormones. The precise mechanisms are not fully understood, but what should be clear is that evolution over hundreds of millions of years is unlikely to have led to a system with obvious flaws. Suppose an animal would need to expend a bit more energy to get to its food source and that food source would yield just a little less energy. If that negative energy balance, however small, would not be neutralized, that animal would eventually starve to death. E.g. if you eat one dry sandwich of, say, 80 Kcal less per day, and your body would not compensate for that, then this would become a deficit of 8000 Kcal in 100 days which would yield 1 kg weight loss. This means that you would lose 100 kg of weight in 27 years time. Obviously the metabolic rate will simply be adjusted to prevent this from happening. But this then also means that you shouldn't gain weight if you eat a bit more.
What goes wrong in people who need to diet to keep their weight from increasing is that they operate their bodies so far out of its design parameters that the feedback mechanisms that would normally keep the weight constant don't work well enough. If you exercise hard enough then the body will take care of its own weight. Count Iblis (talk) 03:06, 8 April 2015 (UTC)[reply]
[citation needed]. Your theory, as I understand it, is if you take someone who is in energy balance, i.e. Calories consumed = Calories expended, and increase or decrease their intake by a small amount then their weight won't change. Your explanation is that the body will simply know if they are eating more (or less) and adjust their BMR to compensate. That's an experiment that could very well be done. Certainly it could be done in animals, and probably even in humans if they would consent to being monitored closely enough. My guess though is that your theory just isn't true. I find it more likely that cause and effect is the following: small food imbalance -> small change in weight -> small change in BMR until stable again. Keep in mind that BMR is directly dependent on weight. Heavier people use more energy for the same activities. In humans, this translates to roughly 12 kcal / day / kg of weight. In your hypothetical example of a person who was 80 kcal out of balance, the natural response would seem to be to lose 6.5 kg. At that point the same activities would require roughly 80 kcal less energy than they did before, and the person would again be in balance. Rather than BMR magically changing in order to maintain a specific weight, I believe that their BMR would change primarily in direct response to weight gain / loss. Such changes would already provide the stabilizing effect that limits the weight impact of small dietary imbalances, without needing to assume the body automatically knows if you are slightly out of balance. Dragons flight (talk) 16:31, 8 April 2015 (UTC)[reply]
There is some evidence for it, see here: "There is evidence that the hypothalamic-pituitary-thyroidal axis is regulated, at least in part, by leptin. This provides an important interface between adiposity, regulated by leptin, and metabolic rate, regulated by thyroid hormones. The mechanisms underlying the connection between adipose signals and energy expenditure include the regulation of the synthesis and secretion of TRH (thyrotropin releasing hormone) by leptin, through the mediation of input from the arcuate nucleus to the TRH neurons in the paraventricular nucleus (PVN) [1]. In addition, the thyroid axis is also indirectly regulated by leptin's actions on the melanocortin pathway, as alpha-MSH (melanocyte stimulating hormone) stimulates and AgRP (agouti-related protein) blocks TRH release [2]. Furthermore, leptin has direct effects on TRH neurons, regulating its synthesis not only by up-regulating the expression of the proTRH gene in the PVN [3] and by influencing the feedback regulation of the TRH-secreting neurons by thyroid hormones, but also by increasing promoter activities of the prohormone convertases PC1/3 and PC2, essential for the activation of TRH from proTRH [4]."
Thing is, as you point out, if all of the feedback were due to the weight, then the 80 Kcal energy imbalance would require a 6.5 kg change in weight, but that's huge! If I were to eat just one sandwich less per day, 15 instead of 16, then my current weight of 55 kg would become less than 48.5 kg (the dry sandwich alone is 80 kg, but of course, I don't eat dry bread). Or if I were to eat just one piece of sandwich more, my weight would increase to more than 61.5, which is a huge gain in weight. Or you could lose weight by wearing heavier clothes, you would lose exactly the extra weight you would start to wear. Count Iblis (talk) 02:43, 9 April 2015 (UTC)[reply]

Addiction

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How do people get addicted to non-addictive things like gardening, knuckle cracking, or watching porn? Obviously I understand how people get addicted to marijuana and other substances because it is a drug. — Preceding unsigned comment added by Arduino12345 (talkcontribs) 19:53, 6 April 2015 (UTC)[reply]

"The term addiction is also sometimes applied to compulsions that are not substance-related," - Addiction#Behavioral_addiction, we have articles on Behavioral_addiction and Addictive_behavior. The term "addiction" is also often used sloppily, see e.g. Addictive_behavior#Compulsion_vs_addiction and compulsion for some related things. SemanticMantis (talk) 20:18, 6 April 2015 (UTC)[reply]

With things like gardening, knuckle cracking, or watching porn, people grow a need to do these things because it provides them some sort of pleasure. This is because when one uses drugs or do activities they enjoy, it elevates the levels of dopamine in the brain increasing the level of pleasure you receive from the action. This even happens when you get good grades, so because those activities you mentioned would bring pleasure to the people doing them they are more likely to continue doing those activities because it provides a euphoric feeling to them.

Here are some sources with information on this topic: http://content.time.com/time/magazine/article/0,9171,986282,00.html http://www.helpguide.org/harvard/how-addiction-hijacks-the-brain.htm http://www.peele.net/lib/diseasing6.html BHope95 (talk) 20:39, 6 April 2015 (UTC)[reply]

I suffer from Trichotillomania and can tell you there is no "pleasure" involved, it's very annoying.. Vespine (talk) 00:04, 7 April 2015 (UTC)[reply]
Have you tried shaving your head? ←Baseball Bugs What's up, Doc? carrots02:03, 7 April 2015 (UTC)[reply]
Come on, Bugs, seriously, what's the point of this? Vespine presumably shared their condition in order to illustrate an important distinction between different types of compulsion, not to invite obvious lifestyle suggestions made as if they were a complete simpleton. Seriously, what kind of response were you expecting here? "Shay-veeng? What is this Shay-veeng you speak of"? I'm half surprised you didn't wikilink shaving. Snow let's rap 04:24, 7 April 2015 (UTC) [reply]
Very prescient of you Snow. For the record, 1) It's not on my head, it's actually my beard and 2) shaving does not help; You can't shave off every single ingrown, stubble, bump, pimple and even if you could by the afternoon there would be more than anough to continue. There's never a shortage of something on my face or neck to inadvertently pick at. It started about 8 years ago when I quit smoking, and now I'm pushing 40, so I do not fit the typical trich profile. It's not quite so bad that I need medication for it, but I have seen a few doctors who have suggested a few things that have so far not worked. I have not yet tried hypno or "proper" behavioral therapy. I did not intend to hijack this thread, I'm thinking that maybe admitting and "confessing" my problem might help with my continuing struggle to stop doing it, I suspect at least it won't hurt.. :) Vespine (talk) 04:58, 7 April 2015 (UTC)[reply]
My question was sincere, and I see from what you're saying that someone with that compulsion will find a way. It's often said that when you stop one addiction you substitute another. ←Baseball Bugs What's up, Doc? carrots05:46, 7 April 2015 (UTC)[reply]

Not to put too fine a point on it, but not all habits are addictions. I have a habit of drumming my fingers (and, over the course of a lifetime, I've become quite adept at producing very complex and rapid rhythms using only the five fingers of one hand). It's a nervous habit which would be very difficult to stop, but I don't think any professional would call it an addiction. I think the same applies to knuckle-cracking. ―Mandruss  05:59, 7 April 2015 (UTC)[reply]

Well, except that there is some (disputed) evidence that popping of the joints can cause long-term degradation of musculo-skeletal strength. And as the distinction that you seem to be making is based on genuine harm done, that is minimally relevant. [8] Snow let's rap 06:09, 7 April 2015 (UTC)[reply]
Yes, my lay person test for addiction (and one that at least approximates that used by a large number of professionals) goes as follows. Is it causing significant harm to your life or the lives of others? Is it impossible to stop without being forced to, despite knowing that? If both are yes, it's an addiction. ―Mandruss  06:16, 7 April 2015 (UTC)[reply]

Can an animal genetically engineer itself?

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I've been reading about some of the techniques used in genetic engineering, such as Electroporation, Sonoporation, and Vector (molecular biology); and I was wondering whether it would be possible for an animal to use any or these or other methods to introduce it's own DNA into foreign cells that are within it's body. The article for electroporation says hundreds of volts are normally used to introduce new DNA into cells a few millimeters away; however electric eels produce 600 volts of electricity [9]. The Emerald sea slug has genes from an algae that it passes on to it's descendants [10]. Bullets and Bracelets (talk) 21:35, 6 April 2015 (UTC)[reply]

Yes, in fact it happens all the time, it's called Horizontal gene transfer. Vespine (talk) 23:01, 6 April 2015 (UTC)[reply]
Remember, eels aren't designed to shock themselves, especially internally. They're relatively shock resistant, ensuring electricity will take the easiest path, so even if they wanted to electroporate, I don't think they could. A lot goes into the process beside voltage. I doubt an eel has the brainpower to even begin wanting to actively try.
If the right lightning bolt hit the right river at the right time, maybe something would accidentally fuse, but I'm no expert. InedibleHulk (talk) 23:54, 6 April 2015 (UTC)[reply]
Tardigrades are supposed to be pretty good at repairing genetic damage to themselves, if that counts. ←Baseball Bugs What's up, Doc? carrots18:25, 7 April 2015 (UTC)[reply]
Part moss, part piglet. Not bad! InedibleHulk (talk) 18:33, 7 April 2015 (UTC) [reply]
Or there's even better, part pigs, part trees. μηδείς (talk) 05:02, 10 April 2015 (UTC)[reply]