Wikipedia:Reference desk/Archives/Science/2011 July 18

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July 18

People like you killed Copernicus!

Or "People like you laughed at Einstein!" - I'm sure that a lot of us who've been around the internet for a while will have seen various crackpots and cranks make statements along those lines (if not those precise statements) by way of rebuttal when their new scientific theories are met with derision or incomprehension by all those that they're talking at. What would be the correct term to refer to this particular logical fallacy? --Kurt Shaped Box (talk) 01:40, 18 July 2011 (UTC)

According to our article, Copernicus died peacefully at the age of 70. AndyTheGrump (talk) 01:49, 18 July 2011 (UTC)

Indeed. Which is what makes it an even sillier statement. --Kurt Shaped Box (talk) 01:54, 18 July 2011 (UTC)

That's what THEY want you to think. He was actually cracked over the head with a pot in the observatory by Colonel Mustard's great-great-great-great grandfather. Clarityfiend (talk) 02:46, 18 July 2011 (UTC)

I don't know a term but it made me think of the crackpot index at http://math.ucr.edu/home/baez/crackpot.html. PrimeHunter (talk) 01:57, 18 July 2011 (UTC)

I'm not sure that ignorance is a 'logical fallacy'. But yes, there ought to be a term for the 'They laughed at X!/Murdered Y!' argument, though I'm not sure it qualifies as a fallacy as such. I suspect this question might get a better answer on the language reference desk. AndyTheGrump (talk) 02:03, 18 July 2011 (UTC)

Aristophanes allegedly said "Ignorance can be cured, but stupidity is forever". HiLo48 (talk) 02:21, 18 July 2011 (UTC)

"The fact that some geniuses were laughed at does not imply that all who are laughed at are geniuses. They laughed at Columbus, they laughed at Fulton, they laughed at the Wright brothers. But they also laughed at Bozo the Clown." -- Carl Sagan (1979.) 99.24.223.58 (talk) 02:28, 18 July 2011 (UTC)

• Maybe the fallacy is a type of Association fallacy? --Jayron32 02:48, 18 July 2011 (UTC)

Persecution complex, Delusions of grandeur, also click Fallacy Taxonomy and scroll down under Informal Fallacy to Guilt by Association (next to "Hitler Card"). μηδείς (talk) 02:53, 18 July 2011 (UTC)

"A measure for crackpots" at [1] (page 10 in the PDF) calls it the "Fulton non sequitur" with reference to steamboat inventor Robert Fulton. But "Galileo Gambit" is a more common name, of course referring to Galileo Galilei. Galileo Gambit was formerly an article [2] but now redirects to Association fallacy. PrimeHunter (talk) 02:59, 18 July 2011 (UTC)

I think that in general people are just oblivious to being wrong, especially when they have a lot of reasons that they think are good for being right and it really doesn't take that much of a persistent error for this effect to occur. I'm thinking this is a kind of like the butterfly effect of misconceptions, and its probably related to memes. But I reckon the persecution complex happens more or less due to a lack of comprehension of the issues involved when the crank gets wound up over their misconceptions. --Modocc (talk) 04:49, 18 July 2011 (UTC)

Effing relativists drive me up the wall! What I like to point out is that no one laughed at Newton and his three hundred year old theories are what got the rockets to the moon! Vespine (talk) 06:44, 18 July 2011 (UTC)

Newton was laughed at in the form of a lampoon. When he insisted that divine intervention would eventually be required to reform the planetary system, due to the slow growth of instabilities, Leibniz lampooned him: "God Almighty wants to wind up his watch from time to time: otherwise it would cease to move. He had not, it seems, sufficient foresight to make it a perpetual motion." Cuddlyable3 (talk) 14:07, 18 July 2011 (UTC)

It’s only been in the last couple of decades that the Catholic Church has finally come out and apologised for labelling the entire Jewish race as “Christ-killers”, and maintaining that judgmental attitude for close on 2,000 years. The irony is that if Christ had not been crucified, there would have been no resurrection, no fulfilment of the prophecies, no Church, and no priests, bishops, cardinals or popes. -- Jack of Oz ^{[your turn]} 06:53, 18 July 2011 (UTC)

Did they claim Jesus committed suicide, because he was Jewish too. Googlemeister (talk) 13:11, 18 July 2011 (UTC)

"Oh, but that's different". -- Jack of Oz ^{[your turn]} 13:18, 18 July 2011 (UTC)

There is indeed a logical fallacy in this sort of attack on a person who challenges someone else's view. Any opinion or point of view will be held by a large number of people - people of all levels of knowledge and skill. It is illogical to attack one person, or a small number of people, when there is an unknown large number of people who hold the same view. To attack one or more people instead of attacking the principle is an ad hominem attack. On most significant matters of principle, an ad hominem attack will be considered irrelevant by many people. Dolphin (t) 13:57, 18 July 2011 (UTC)

(OR)British magistrates have been criticized for addressing a black defendant as "you people". Thus have I heard. Cuddlyable3 (talk) 14:12, 18 July 2011 (UTC)

Ah, yes - 'You people...'. Two little words that if placed at the beginning of a statement, leave me with little hope that the words that follow will have any real value or sense to them. It's the same feeling I get when someone starts off with 'God told me to...'. --Kurt Shaped Box (talk) 14:34, 18 July 2011 (UTC)

Thermodynamics for beginners

Can someone confirm that I'm not talking complete bullpoop over at the computer reference desk: [3] is it a reasonable assumption that a hard disk drive consuming 10 or 12 watts under load is inevitably going to output something very nearly approaching the same amount of heat? Someone has posted a link that seems to imply it produces more than this, which seems absurd, but I can't help thinking that it is unlikely to produce much less, either. Other than the output signal (which I'd perhaps naively assume wouldn't be in the watt range), any outputs have to be as heat, or other non-ionising radiation (I hope I've got the terminology right here), or as sound/vibration - and that if significant parts of the output aren't as heat, it isn't likely to be good for the computer, the user, or both? AndyTheGrump (talk) 03:20, 18 July 2011 (UTC)

First law of thermodynamics says that you cannot get more out than you put in, in terms of energy. Power is not energy, so you need to make sure that you use your terms correctly. But generally, yeah, you cannot get more joules of heat out than joules of energy you put into a system. Power (physics) is energy per unit time. Things like "Force", "energy", and "power" (and their units of newtons, joules, and watts) frequently get confused. Its important to be precise in what you are discussing. Furthermore, heat is rarely measured in "watts" because Power is usually most useful as a unit of "work". When you see something like the wattage of a space heater, what is being measured is the input wattage; the output of the heater is usually quoted in units like British thermal units, which is merely another unit for energy (like a Joule or a calorie). As far as the crux of the dispute, I think what the source link is saying isn't that a HD produces more heat than it's own input of energy, what it is saying is that the energy in/heat out ratio in a HD is much higher than the energy in/heat out ratio in a CPU because of the large amounts of heat generated by the moving parts. --Jayron32 03:32, 18 July 2011 (UTC)

You're right. This was also pointed out in one of the blog comments. -- BenRG (talk) 04:24, 18 July 2011 (UTC)

Yes AndyTheGump is right. The link in question is incorrect. While it does not contain Jayron32's absurd phrase "more heat than it is own input of energy", it wrongly refers to "generating a lot of mechanical movement, which means friction-- and heat disproportionate to the power input". The writer's error could be to regard friction as a heat source that is independant of the electric power input, which it is not, or to have omitted the word "idle" from "disproportionate to the idle power input". Cuddlyable3 (talk) 14:39, 18 July 2011 (UTC)

I believe what I said was, and I quote (bolded because you misquoted me) was that "the source link is saying isn't that a HD produces more heat than it's own input of energy". You are intelligent enough to understand what that sentence means, so I am not sure why you deliberately said it was "absurd" that I would note that. --Jayron32 15:50, 18 July 2011 UTC)

English writers are familiar with the contraction "it's" which means "it is". Some are not so fortunate as to have mastered educated English, but we who are so blessed can often figure out what a person is trying to say. Does your post mean that you now wish to discuss a subject that you earlier dismissed[4] as uninteresting? Cuddlyable3 (talk) 16:15, 18 July 2011 (UTC)

I believe before I asked you to stop pretending that this was a problem. --Jayron32 17:06, 18 July 2011 (UTC)

I think what we see here is unnecessary friction between two parts producing more heat than light... --Stephan Schulz (talk) 18:05, 18 July 2011 (UTC)

PARTICLE ACCELERATION

1)how can we accelerate hadrons? 2)can Ions heavier than proton and alpha and beta rays for example Ionized carbon and nitrogen and oxygen isotopes be accelerated  ?--Akbarmohammadzade (talk) 03:27, 18 July 2011 (UTC)

1. Controlled fluctuating magnetic fields.
2. Yes, they can.

Plasmic Physics (talk) 04:21, 18 July 2011 (UTC)

1) Big, electrically charged plates or big magnets do the trick usually. One of the simplest types of particle accelerators is a cathode ray tube, of which you are very familiar as nearly every television set and computer monitor prior to about 10 years ago was built with them. But all particle accelerators work on the same basic principle: You have electrically charged plates which focus and accelerate a beam of particles. The difference between a CRT and the large particle accelerators is like the difference between a bottle rocket and a Saturn V rocket, but the basic principle is the same.

2) Absolutely. Ions of any size can be accelerated, that's the principle behind mass spectrometry; which generally involves two phases: generate ions, then accelerate the ions using electrically charged plates. Mass spectrometry techniques like MALDI are done on superhuge molecules like proteins and nucleic acids.

You might want to read the article titled particle accelerator or Large Hadron Collider. --Jayron32 04:44, 18 July 2011 (UTC)

You might also enjoy reading Relativistic Heavy Ion Collider where, of all things, heavy ions are accelerated. Dauto (talk) 15:31, 18 July 2011 (UTC)

2) If I electrically charge myself, by walking on carpet with socks, for example, it will be possible to accelerate me the same way they do hadrons. Incidentally, you can just say protons. You can accelerate any hadron (although ones with neutral charge will be harder to accelerate), but the Large Hadron Collider just uses protons.

cancer pain

Do cancer cells have active pain receptors? Is the pain of cancer during medications because of the action against cancer cells? that is, the medication kills the cells and hence the pain? — Preceding unsigned comment added by 199.224.149.10 (talk) 08:47, 18 July 2011 (UTC)

People who have cancer and are feeling pain need to inform their doctor immediately. We cannot give any medical advice. There are many causes of cancer pain, but most cancer pain occurs when a tumour presses on nerves or body organs, or when cancer cells invade bones or body organs. Cancer treatments such as chemotherapy, radiation or surgery also may cause pain. Cuddlyable3 (talk) 13:51, 18 July 2011 (UTC)

That's not really an answer, the OP stipulated the conditions of the cancer pain, which you simply repeated back at him/her. Plasmic Physics (talk) 14:15, 18 July 2011 (UTC)

True. As unqualified strangers on the Internet we may not offer unsourced medical information. Cuddlyable3 (talk) 16:25, 18 July 2011 (UTC)

The OP did not say "my cancer..." or "my friend's cancer...," nor did he seem to be playing games by asking for medical advice in the guise of a general quest for information about a topic. Just like Real Life Reference Librarians, we are allowed to refer such questioners to Wikipedia article, or other reliable sources such as books or journal articles. Such sourced info is, logically, not "unsourced." Edison (talk) 18:45, 18 July 2011 (UTC)

(EC) Well, how about some sourced physiological information, then? I myself do not (to my knowledge) have cancer, or (to my knowledge) personally know anyone who currently has, but I still find the question interesting in purely biological terms. So, perhaps, might the OP, who has given no overt indication of being in a different situation to my own. Why don't we assume good faith in the OP's not having covertly asked for a personal diagnosis? (The poster formerly known as 87.81.230.195) 90.201.110.154 (talk) 18:55, 18 July 2011 (UTC)

(EC) Since curiosity about cancer is not a request for medical advice, it's legitimate to actually provide some actual information here. Generally, cancer cells are of a certain type which determines the type of cancer, and therefore tumors themselves don't have pain receptors. Cancer pain is of various types, including that due to injury to surrounding (non-cancerous) tissue, called nociceptive pain; another type is neuropathic pain caused by the tumor's stimulation of nerves. Sometimes, during chemotherapy, there is neuropathic pain which ceases after the chemo is discontinued. The questioner can find references in the linked articles. - Nunh-huh 19:04, 18 July 2011 (UTC)

""Medical advice"? What hysterical nonsense!

No, in order for one to feel pain because of what is happening to the cancer cells themselves, they would need to be properly innervated by neurons carrying cells to the CNS, an unlikely case. Pain is likely the result of pressure exerted by a tumor on tissues with pain receptors, or the negative side effects of treatments on living tissues. μηδείς (talk) 21:27, 18 July 2011 (UTC)

I don't know this one, but briefly looking into the literature (no further back than 2010 on PubMed!), here are some ideas. Metastatic breast cancer in bone has the ability to cause bone cells to change from those that create bone to those that break it down (osteoclasts) resulting in osteolysis and pathological fractures. (see [5] and ref. 16) According to a recent general review of the mechanisms of cancer pain [6], breast cancer sufferers will almost certainly not feel pain in the breast, but rather usually feel the pain when metastasis occurs to the skeleton. The pain is in part due to an acidic environment, here due to osteolysis but apparently a more general characteristic of cancers - "acidosis is a well-established cause of pain", they say, and the acid is produced "adjacent to the well-innervated periosteum".

Additionally, according to the review, there is a chemical means of pain enhancement (hyperalgesia) from endothelin-1, though tumors can produce either this or an antagonistic molecule. Such pain is typical of squamous cell carcinoma but not melanoma. They also can produce bradykinin with a closely related effect. Cancers can also enhance growth with nerve growth factor, possibly linked to perineural involvement where the tumor actually invades a nerve - this is associated with pancreatic cancer. Apparently anti-NGF is a potent means of treatment.

Proteolysis has a role also - the cancers produce trypsin and other proteases and more or less literally digest the surrounding tissue. Cells have receptors (PAR2) which cause pain ("mechanical allodynia") when they receive fluids associated with cancer cells.

Much of the preceding is from that review [7] which is public access and a good starting point for further reading. But one thing it fails to cover is "breakthrough pain", which is mentioned only in the abstract and the conclusion. According to [8] (another free article) it is often due to the skeletal metastases described above, but can come from neuropathic causes, the end of a dose of painkiller, or other reasons. There is a great deal of literature about it, mostly technical papers about fentanyl. Wnt (talk) 12:35, 19 July 2011 (UTC)

How does vo2 max work?

The article vo2 max doesn't really explain the biochemical process behind it. Why do trained people have a higher oxygen uptake? I'm assuming it's something to do with the binding of Oxygen to haemoglobin. Is this also related to how some untrained people can faint/feel sick after intense exercise, presumably due to oxygen insufficiency or is that related more to insufficient glucose? Thanks. Clover345 (talk) 11:38, 18 July 2011 (UTC)

Haemoglobin -Oxygen binding biochemistry is not affected by training. What changes are the cardiac output and the lung physiology. Trained athletes have bigger, stronger hearts that pump more blood- drawing more oxygen out of the air per minute. The lung structure also will affect how much oxygen is absorbed - healthy large lungs without scar tissue or phlegm that are highly elastic are better. (older people have relatively inelestic lungs- the stale oxygen depleted air isnt expelled properly when they breath out) To a certain level the lung can adjust how efficient it is readup on the ventilation perfusion ratio. Training also makes the muscles more efficient for a type of aerobic activity by increasing the blood supply to the muscles over the long term. Hope this is useful.Staticd (talk) 13:37, 18 July 2011 (UTC)

Thanks. Does this mean that the actual biochemical process of respiration is unaffected by training and that the change is more physiological? Clover345 (talk) 14:42, 18 July 2011 (UTC)

By "biochemical process" if you are speaking about the affinity/saturation of Hb by Oxygen, then as far as i know, no that's more or less entirely genetic and constant for all people. However i forgot to mention another change - that the number of RBCs goes up with certain kinds of training- especially at high altitude. cheerio. Staticd (talk) 04:31, 19 July 2011 (UTC)

Electronic wristwatch movement

Resolved

I have a battery-powered wristwatch with mechanical hands. A few weeks ago it was accidentally submerged in water (it's not designed to be waterproof). Since then, the second hand moves at four-second intervals: i.e. it doesn't move for four seconds and then jumps forward four seconds in one go. I find this behaviour puzzling. I'd have thought that if it were 'sticking' then the behaviour might vary a bit depending on which way up the watch is, whether I shake it, etc. but it's completely consistent. I've read the Electronic Movements section of the wristwatch article but don't understand how the gearing works. I'd like to know more about how the quartz oscillations are converted into a mechanical movement and what might have happened to my watch mechanism to cause it to behave in this way. --Frumpo (talk) 12:18, 18 July 2011 (UTC)

Is it possible that your battery is getting low? Maybe by moisture contamination or just coincidentally. My watch has certain movements of the second hand to indicate the health or otherwise of the battery. It would help if we knew what make and model of watch we are discussing. Richard Avery (talk) 13:20, 18 July 2011 (UTC)

Genius! It hadn't occurred to me that this might be deliberate behaviour. It's a Longines L4.720.4. I've just found an instruction manual online and it says "Some models have a battery end-of-life function. The seconds hand will start to jump every 4 seconds." Thanks very much! --Frumpo (talk) 13:47, 18 July 2011 (UTC)

Aegis radar system

I have heard some US Navy folk joking that if you irritate the captain of an Aegis cruiser, he can use his radar on you and cause birth defects in your future children. Now from what I know about the Aegis radar system, it is able to project 6 megawatts of power down 1 degree of bearing (supposidly they could get a radar return off the moon). While that is impressive, I don't think radar is an ionizing form of radiation so I am skeptical about those effects. So have there been cases of radar exposure causing sterility or having tetrogenic effects? If so, what would be the equivalent distance to a Aegis radar at full power for those effects? Googlemeister (talk) 14:33, 18 July 2011 (UTC)

There has never been a conclusive study which has shown that radio waves cause an increase in cancer risk at any intensity (or indeed, any ill effects whatsoever). You are indeed correct to suspect that radar (at least at conventional wavelengths) is not ionizing radiation (this is a good read on the topic). The warning signs you see on radio towers are mostly out of an abundance of caution; it's probably not a good idea to pump large amounts of anything through your body, just to find out what happens. And if the radiation is intense enough, there's always a chance it can heat an object to the point of burns, but (someone correct me if I'm wrong) it would take Gigawatts or more at close range to cause this to happen.

I'm sure the story was in jest. The guy who taught me how to use our 1 MW radar often said he would point it down at our cars in the parking lot to disable them, but I knew he was joking. -RunningOnBrains^(talk) 15:43, 18 July 2011 (UTC)

I'm not sure causing greivous birth defects is part of the Uniform Code of Military Justice, so I might take the claim with a few very large grains of salt... --Jayron32 15:43, 18 July 2011 (UTC)

However I am completely sure it is not. If that were so, it would be grievous not "greivous". Cuddlyable3 (talk) 15:58, 18 July 2011 (UTC)

Male sterility is a known side effect of radiation treatment of cancer but this not a safe alternative to vasectomy for contraception. During WW2 Himmler authorized sterilization experiments to take place at Auschwitz Concentration Camp. The AN/SPY-1 radar in Aegis transmits in the range 2 to 4 GHz. I can't confirm whether the 6 MW rated output is a short-term peak or if it is possible to send continuously, or whether the phased array antennas can focus on the crotch of an irritating seaman in the near field. (OR) Workers on Distant Early Warning Line stations warmed themselves by standing in front of the radar antennas, without documented ill-effects AFAIK. I think you meant teratogenic. The main sign of anything affecting Semen quality is reduced sperm Motility which can be caused by radio waves including, it has been suggested, those from a mobile phone in the pocket. Cuddlyable3 (talk) 15:52, 18 July 2011 (UTC)

Radiation doesn't have to be ionizing radiation to cause you harm. What do you think will happen if you put a cat inside of a microwave oven and press start - don't actually try that experiment. Just think about it. Dauto (talk) 16:02, 18 July 2011 (UTC)

Shame on you Dauto for even thinking of such a catastrophe. Cuddlyable3 (talk) 16:20, 18 July 2011 (UTC)

Getting an echo from the moon is trivially easy with a system such as AEGIS. In fact amateur radio operators routinely communicate using the moon as a reflector with a tiny fraction of the power available to an AEGIS radar. With modern digital signal processing 100 watts is enough. Roger (talk) 18:32, 18 July 2011 (UTC)

I don't know how the frequencies and power compare, but a friend worked on MIM-23 Hawk missile radar systems in the US military, and after his years of service developed cataracts in his 30's. Several of his friends from the service who worked on the radar systems developed cataracts as well at an early age. Edison (talk) 18:41, 18 July 2011 (UTC)

Cataracts develop for a variety of reasons that do include exposure to radiation, see Cataract#Causes. The article MIM-23 Hawk#Radars gives some information on frequencies and powers. Cuddlyable3 (talk) 20:19, 18 July 2011 (UTC)

A six-megawatt radar beam can cook you quite nicely if you get too close to the transmitter, but I don't think it can be focused tightly enough to just cook your reproductive organs. --Carnildo (talk) 00:08, 20 July 2011 (UTC)

When will Dawn transmit new photos of Vesta?

The latest photo taken of Vesta by Dawn (spacecraft) is over a week old, taken July 9. Is there any news as to how long it will be before new images are transmitted, and what procedures they are working on now? --George100 (talk) 18:56, 18 July 2011 (UTC)

Well our article says

Dawn was scheduled to be inserted into orbit at 05:00 UTC on July 16 after a period of thrusting with its ion engines. Because its antenna is pointed away from the Earth during thrusting, scientists were not able to immediately confirm whether or not Dawn successfully made the maneuver. The spacecraft would then reorient itself and was scheduled to check in at 06:30 UTC on July 17.[24] NASA later confirmed that it received telemetry from Dawn indicating that the spacecraft successfully entered orbit around Vesta.[25] The exact time of insertion has not been confirmed as it depended on Vesta's mass distribution, which has only been estimated.[26]

A quick search finds the mission status which says something similar and also the news page [9] again saying something similar. This would suggest they have more important things likely taking up communication time with the probe, like confirming the details of the orbit, making sure it is okay etc.

Of course it's possible they've already received more images, simply not have the time to process them or otherwise decided not to release them yet. For example, the general image page [10] shows they were releasing an image about every 7 days or so. The page you linked to shows the image was taken on the 9 July and release on 14 July. The mission status page confirms Vesta was observed on the 12 and the 16th, these images whether received on earth or not evidently haven't been released yet.

BTW I noticed the mission status page also says:

The change in the thrust schedule does not affect the plan for the intensive Vesta science observation phase, which begins in August.

Nil Einne (talk) 20:54, 18 July 2011 (UTC)

I've found some additional info to my question on the Faq page:

"Why aren't there more images of Vesta on the webpage?"

The spacecraft has to stop thrusting and turn to take a picture of Vesta and then turn again to send it back to Earth. We do not want to stop thrusting often or for long thus we only take "nav" pictures occasionally. These pictures are necessary to determine the exact position of Vesta using the location of the background stars. These are the pictures we are currently posting.

--George100 (talk) 18 July 2011 (UTC)

Saturday's photos are up now: http://www.nasa.gov/mission_pages/dawn/main/index.html thx1138 (talk) 21:24, 18 July 2011 (UTC)

Update: the first picture from orbit just came in. Looie496 (talk) 02:28, 19 July 2011 (UTC)

I would much rather have some close up pictures of asteroid SO16 2011, which is in a very unlikely orbit for objects its size, and at a very peculiar place along it at the moment. 99.2.148.119 (talk) 05:25, 19 July 2011 (UTC)

What's that slip face like structure in the upper right ? Sean.hoyland - talk 08:30, 19 July 2011 (UTC)

"Slip-face" is probably not far wrong. In that photo of Vesta, which is looking roughly at the body's south pole, almost the whole of the visible hemisphere is occupied by an enormous impact crater, with a central uplift mountain such as is commonly seen in large craters on the Moon and other solar system bodies. The feature you mention is part of the inner side of the outer rim of the crater. {The poster formerly known as 87.81.230.195} 90.201.110.222 (talk) 19:03, 19 July 2011 (UTC)

Anabolic steroids and testosterone

What is the difference between anabolic steroids and testosterone? Are they two completely different things? Or are they two different words for the same thing? Thanks. (Joseph A. Spadaro (talk) 20:26, 18 July 2011 (UTC))

What part of:

Anabolic steroids, technically known as anabolic-androgen steroids (AAS) or colloquially simply as "steroids" or "'roids", are drugs which mimic the effects of the male sex hormones testosterone and dihydrotestosterone. They increase protein synthesis within cells, which results in the buildup of cellular tissue (anabolism), especially in muscles. Anabolic steroids also have androgenic and virilizing properties, including the development and maintenance of masculine characteristics such as the growth of the vocal cords, testicles, and body hair (secondary sexual characteristics).

(and the rest of the article) needs further clarification? Nil Einne (talk) 20:58, 18 July 2011 (UTC)

Testosterone is an anabolic steroid in the same way that aspirin is a pain reliever -- it is one of many. Looie496 (talk) 21:03, 18 July 2011 (UTC)

(ec)Testosterone is a single compound. Anabolic steroids are a group of related compounds, some naturally occuring, some synthetic. In the classification used in the article, testosterone is a gonadal anabolic steroid. I sense a slight contradiction between the lede that Nil Einne reproduced, and the section on gonadal anabolic steroids, as the lede seems to exclude the naturally occuring componds from the definition, and include only substances that mimic them. --NorwegianBlue ^talk 21:14, 18 July 2011 (UTC)

Thank you. So, testosterone is a specific form of an anabolic steroid (which is a generalized term). Is that correct? Kind of like an analogy such as this: A car is a general term, of which a Honda Civic is a specific example of a car. Thus ... An anabolic steroid is a general term, of which testosterone is a specific example of an anabolic steroid. Is my analogy correct? If so ... besides testosterone, what are some other anabolic steroids out there? I don't think that I have ever heard of any (besides testosterone) ... and, if I recall, the anabolic steroids article did not list any ... which is why I thought that the two terms (testosterone and anabolic steroid) might have simply been two words for the same thing. Please advise. Thanks! (Joseph A. Spadaro (talk) 16:43, 19 July 2011 (UTC))

The Anabolic steroid article lists several compounds, and links to their articles: Methyltestosterone, Fluoxymesterone, Oxymetholone, Oxandrolone, Nandrolone decanoate, Methandrostenolone, Methyltestosterone. --NorwegianBlue ^talk 14:02, 20 July 2011 (UTC)

Thanks for the help! Much appreciated! (Joseph A. Spadaro (talk) 15:08, 21 July 2011 (UTC))

Non-orbital space rockets

Which nations had the first non-orbital rockets? Rockets which got into space but did not necessarily orbit? Britain had the Skylark (rocket) which launched in 1957. What nations were earlier than that? 92.28.249.93 (talk) 21:57, 18 July 2011 (UTC)

Well, the Soviets, of course, had earlier non-orbital rockets. The earliest, as far as I can tell, were the German V-2 rockets, which could reach altitudes higher than 100 miles -- I think that counts as space. Looie496 (talk) 22:33, 18 July 2011 (UTC)

That (pretty arbitrary) delineation is the Kármán line at 100km (except for USAF and NASA, who drastically lower the bar). Sub-orbital spaceflight lists the first unmanned vehicle to reach that altitude as a V-2 in early 1944. Both the US and the Soviet Union grabbed V-2s at the end of WW2 (and the UK a handful), and so made their own launches in the mid to late 40s - see V-2#Post-Second World War usage. -- Finlay McWalter ☻ Talk 22:56, 18 July 2011 (UTC)

So Britain could have been the second nation into space (or "the first allied nation in space" if you want to play the game of defining the rules to suit yourself) except they only got up to 70km according to Operation Backfire (WWII). 2.101.5.83 (talk) 11:20, 19 July 2011 (UTC)

70 km passed the U.S. definition of space (50 miles) during the early space race so you probably could still say it. The U.S. V2 launches started in 1946 and the Soviets in 1947. Rmhermen (talk) 19:38, 19 July 2011 (UTC)

50 miles is 80km. --Tango (talk) 19:45, 19 July 2011 (UTC)

It is a pity there is no article about Britain's achievements in space, as it had a few early satellites and rockets. 2.97.220.86 (talk) 21:06, 19 July 2011 (UTC)

Why only one subspecies of humans survived

What were the factors that led to the extinction of all Homo species and even subspecies except Homo sapiens sapiens? I particularly wonder because many of Homo seemed to be life-capable and not practising cannibalism. --188.146.69.140 (talk) 23:44, 18 July 2011 (UTC)

They probably couldn't compete with our species. Dauto (talk) 23:48, 18 July 2011 (UTC)

Such things are hard to determine. See Neanderthal extinction hypotheses for the Neanderthals. PrimeHunter (talk) 00:28, 19 July 2011 (UTC)

Species are defined as those populations which are genetically isolated--biological species concept--i.e., that don't interbreed. We have evidence that Denisova and Neanderthal man did interbreed with Homo sapiens sapiens, hence they did not go extinct any more than any of our ancestors have gone extinct. Their subpopulations were absorbed into wider humanity. And if 2.5% of extra-African genes are Neanderthal, then there are the equivalent of ~125,000,000 (.025 X 5,000,000,000) "man/genomes" worth of Neanderthals living today--far more than ever lived when they were an isolated population. μηδείς (talk) 01:33, 19 July 2011 (UTC)

It should be noted that while the above is stated as fact, as our extinction hypothesis article points out, it is just one of many competing theories. (And you've made a mess of the biological species concept. It's not that they interbreed. It's that they produce fertile offspring. There's a big and important difference there.) --Mr.98 (talk) 01:50, 19 July 2011 (UTC)

Do you deny, Mr.98, that the concept of Mayr's that I linked to is perfectly applicable for the point I made, or relevant to the question asked?

As for whatever "mess" it is you think you are pointing out--if there is any, as your statement is unclear--the relevant point is that isolated populations themselves don't interbreed--there is no gene flow--even when occasional individuals interbreed to produce infertile hybrids. Next time I should provide a blue link for anyone who might be confused...Oh, wait....

As for "stated as fact", I said "We have evidence that..." and I said "And if 2.5% of extra-African genes are Neanderthal..." That is hardly claiming that the evidence is conclusive or the conclusion is viewed as fact.

You need to learn to distinguish between what people have actually said themselves and your own outrage-generated straw men caused by not reading them reasonably, and to stick to the former, not the latter, as the basis of your criticism.

μηδείς (talk) 02:28, 19 July 2011 (UTC)

I think Mr. 98 had a good point that relates to the species problem and speciation. As I presume our article notes and in any case we've discussed many times before on the RD, the concept of species isn't as clear cut as many non biologist would like to believe.

Even given that, I don't know if many taxonomists would consider two groups seperate species if they only very recently were genetically isolated and there are still no real genetic or phenotypic differences between the two and they can easily interbreed. For example if some sort of catastrophic activity seperated a landmass in to 2 sufficiently so that some land animals could not cross between the two last year, few would consider animals on either side which would have been considered the same species prior to the seperation as seperate species even though they are genetically isolated today. They will probably be one day presuming both survive and the land masses remain seperate but they aren't now. In other words, no sensible species definition generally considers present day genetic isolation (ignoring the history) the sole arbitrator of seperation between species. (And of course it's possible a landmass may be seperated for only part of a year or a small number of years, even if the animal's generation time is less then the time of seperation you can't really call that genetic isolation if you actually look at the history or predicted future, snapshot in time approach doesn't work.)

The traditional definition has been of the inability to interbreed to produce fertile offspring which would generally arise over time given genetic isolation, but not always even when the species show significant phenotypic adaptations, which partly relates to the problem of defining species. We get complicated things like the many possible Ursid hybrids (some of which are fertile including at least one which occasionally occurs in the wild) and the complex evolutionary/genetic relationship/history of brown bears and polar bears which also demonstrate the idea of 'genetic isolation' and 'able to interbreed to produce fertile offspring' are fairly fussy concepts anyway, as is any definition of 'species'. Reflective of the fact life is a continuum that doesn't always fit into nice little boxes and many things that could meaningfully be considered seperate species probably (with the caveats I'm pretty sure are outlined in our species, species problem and speciation articles) don't arise suddenly.

P.S. Of course we haven't even considered bacteria or archaea where the concept of species itself is questionable although that doesn't really relate to the original question. Nil Einne (talk) 08:45, 19 July 2011 (UTC)

No need to get so defensive. You did just present your statements as if they were cut and dry, and they aren't. I was just making that clear, not criticizing you. Similarly you got the most important part of the biological species concept wrong. Interbreeding is not enough — the resulting offspring must be fertile. My goal was to clarify, not criticize. --Mr.98 (talk) 11:38, 19 July 2011 (UTC)

So your point is, when I said that the subgroups interbred so that 2.5% of the current extra-african human genome is Neanderthal, I should have pointed out that the modern human ancestors produced by such interbreeding were fertile? How many of your ancestors never had children? Once again, the "mess" you are cleaning up is your own straw man. μηδείς (talk) 22:58, 22 July 2011 (UTC)

What does cannibalism have to do with it? Just because a species doesn't eat other similar species (which may or may not have been the case, anyway) doesn't mean that it doesn't kill or marginalize other species. --Mr.98 (talk) 01:51, 19 July 2011 (UTC)

A recent Science News article, "Non-Africans Are Part Neanderthal, Genetic Research Shows", said that research published in the July issue of Molecular Biology and Evolution, had determined that all humans except some in sub-Saharan Africa included Neanderthal DNA in their genome, in the X chromosome. This must be horrifying to elitist scientists who have insisted that THEIR ancestors would NEVER have mated with Neanderthals. (Tell that to farm boys who screwed sheep, per Kinsey). So most of us are descendants of Neanderthals. They interbred with modern humans, likely in the Middle East, and the result was fertile offspring, perhaps with enhanced survival ability, who passed on the Neanderthal DNA to present day humans. Edison (talk) 17:26, 19 July 2011 (UTC)

Although perhaps improbable, we still do not have 100% certainty that all competing subspecies that did not interbreed in fact did fade out. Thus are the unproven cryptids such as Orang Pendek. ~AH1 ^(discuss!) 21:02, 20 July 2011 (UTC)