Wikipedia:Reference desk/Archives/Science/2016 June 13

= June 13 =

Are there any living things in 4+ homographic taxonomic categories?
Gorilla gorilla gorilla is a subspecies of gorilla. None of it's other taxonomic classifications are "gorilla". It's tribe gorillini is close but no cigar. Sagittarian Milky Way (talk) 04:56, 13 June 2016 (UTC)


 * The first thing that pops to mind is Major Major Major Major, but of course that's not really what you're looking for. —Steve Summit (talk) 07:36, 13 June 2016 (UTC)


 * Let me see... Rattus rattus is a rat, Gerbillus gerbillus is a gerbil, Orilus orilus is an oriole, Iguana iguana is an iguana, Conger conger is a conger eel, Puffinus puffinus is the Manx shearwater, Boops boops is the Bogue fish, Mops mops is the Malayan Free-tailed bat, Megacephala (Megacephala) megacephala is a Tiger Beetle subspecies, and, if you are ready, Bison (Bison) bison bison is a subspecies of, you guessed it, bison. To conclude, just remember that Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo. JoshMuirWikipedia (talk) 09:22, 13 June 2016 (UTC)
 * Tautonym is the technical term, and List of tautonyms is the place to research this. No quadruples so far, but it's a long list. Tevildo (talk) 19:30, 13 June 2016 (UTC)
 * Try Cinclus cinclus cinclus, which is in the family Cinclidae. Tevildo (talk) 19:40, 13 June 2016 (UTC)
 * Colius colius, family Colidae, order Coliiformes. I'm going to stop now. Tevildo (talk) 19:49, 13 June 2016 (UTC)

this user enquires the harms that may occur from overconsumption of lemons
6 or more within 24 hours.immideatism for knowledgeFAMASFREENODE (talk) 11:25, 13 June 2016 (UTC)


 * Quoting the notice at the top of this page... "We don't answer (and may remove) questions that require medical diagnosis or legal advice."
 * That said, you might want to read Vitamin C. Dismas |(talk) 12:59, 13 June 2016 (UTC)

in reply to, the enquiry is performed as for general knowledge and refdesk is for itFAMASFREENODE (talk) 13:23, 13 June 2016 (UTC)


 * This indicates it takes a couple of lemons to make a single glass of lemonade. So you're talking 3 glasses to consume 6 lemons. If you have concerns about it, you should contact your doctor. ←Baseball Bugs What's up, Doc? carrots→ 14:49, 13 June 2016 (UTC)

Main Battle Tanks
Why Russian and British tanks have longer guns - main guns - than all other tanks ? Why German tanks have two types of guns, one short and the other is long ? 86.108.73.207 (talk) 13:08, 13 June 2016 (UTC)


 * What era? WWII? The "classic" example of this would be the PzKpfw IV, with the short 75mm and the long 75mm.
 * The first of these was a "heavy tank gun" intended as a dual purpose piece of tank artillery. It could fire either an armour-piercing shell against tanks, or a high-explosive shell against troops or buildings. At the time, this was a powerful tank gun. It was one of the few tanks which could carry such a large calibre (diameter) 75mm gun in a fully rotating turret.
 * The short barrel gives a short length in which to accelerate the shell. A longer barrel gives more length. So for the same round, the long barrel gives greater muzzle velocity. This doesn't matter much with an explosive shell: so long as it arrives, it will explode and do damage according to its filling. For an anti-tank armour-piercing solid shell though, the velocity with which it arrives is what gives it its destructive power. A longer gun will probably use a larger chamber and shell case for the round - the amount of propellant chosen is the amount that can be burned during the shell's travel down the barrel: a longer barrel gives time and space for more. It may need a larger shell case to make use of this though.
 * The first of these two guns was the L/24 variant, the longer was the L/43. This means that their calibre length (the length of the barrel as a number of diameters) was nearly twice as long for the longer barrel. It is more difficult to make the longer gun though: it is larger, harder to make such a long barrel, heavier (so the tank suspension might not cope), has greater recoil forces (so the turret bearing has to be stronger) and will probably use larger ammunition (so fewer rounds can be carried).
 * The US Sherman also had varying barrel lengths. The original gun was another short 75mm but the US lengthened it as the 76 mm gun M1 and the British installed their 17 pdr as the Sherman Firefly. The Fireflies' ammunition was so large (and powerful) that a crew member had to be left out to make room. Andy Dingley (talk) 13:51, 13 June 2016 (UTC)

Well I`m sorry I didn`t mention the era I`m asking about, I meant the third generation era , but the information is useful thank you very much. 86.108.73.207 (talk) 14:57, 13 June 2016 (UTC)


 * The following data applies to current main battle tanks. The Russian T-80 is armed with the 2A46 125 mm smoothbore with a barrel length of 52 calibers (6.0 metres).  The British Challenger 2 is armed with the L30 rifled gun with a barrel length of 55 calibers (6.6 metres).  The American M1A2 Abrams is usually armed with the 44 calibers (5.3 metres) version of the Rheinmetall 120 mm gun.  However, many German supplied NATO armies using this gun have replaced it with the more powerful 55 calibers version where there is a possibility that they will have to face Russian T80s.  So it is debatable whether the OPs contention that only British and Russian tanks have longer guns is correct. SpinningSpark 15:31, 13 June 2016 (UTC)
 * Our article gives a barrel length for the Rheinmetall L/55 of 6.6 m, the same as the L30. Alansplodge (talk) 20:35, 13 June 2016 (UTC)
 * Then I'd agree with Spinningspark. For recent tanks, I can't see a systemic variation between them. Andy Dingley (talk) 15:46, 13 June 2016 (UTC)
 * The Abrams is normally equipped with the L/44, not the L/55, which is indeed a shorter barrel. SpinningSpark 08:36, 14 June 2016 (UTC)

Thank you Spinningspark, Thank you Andy Dingley. 86.108.73.207 (talk) 18:06, 13 June 2016 (UTC)

Brian spider
There's nothing here about it, but it was a topic of Mark Trail several weeks ago. It's a newly discovered species named for someone named Brian.— Vchimpanzee  •  talk  •  contributions  •  20:03, 13 June 2016 (UTC)
 * Actually, we do. Dolomedes briangreenei - see also this article from National Geographic.  [WARNING - Article has large photo of said arachnid].  Named after Brian Greene. Tevildo (talk) 20:34, 13 June 2016 (UTC)
 * Okay, thanks. I just missed it somehow. And apparently I'm glad I did. Here is where I learned about the species.— Vchimpanzee  •  talk  •  contributions  •  20:37, 13 June 2016 (UTC)
 * When I saw that, I assumed it was named after Brian Austin Greene. Thankfully not so. Justin15w (talk) 19:12, 14 June 2016 (UTC)
 * Every time I see this, I first read it as brain spider. Is that a thing?  If not, it should be. --Trovatore (talk) 19:55, 14 June 2016 (UTC)
 * "In some spiders, the central nervous system took up nearly 80 percent of the space in their bodies, sometimes even spilling into their legs." . Salticids in particular are super brainy and smart hunting spiders: some of their hunting techniques are comparable to lions', see Hunting tactics of the genus Portia. For extra cool/creepy points, they huntother, dumber, web-weaving spiders, in part by sending deceptive vibrational signals down the victim's web. So yeah, brain spiders :) SemanticMantis (talk) 22:01, 14 June 2016 (UTC)

Determining month and/or day in GTA by day duration
I'm particularly interested in GTA Vice City and GTA San Andreas. AFAIK, the day duration synched with clock in the upper right corner there is constant (and apparently it's the Northern Hemisphere), so based on day duration and daylight intensity I wonder what month and/or day would it be during the gameplay? Thanx.--93.174.25.12 (talk) 23:12, 13 June 2016 (UTC)
 * It would depend on the latitude of the location. Here's a calculator that shows amount of daylight on a specified day in a specified location: CodeTalker (talk) 23:24, 13 June 2016 (UTC)


 * Day duration for San Andreas, California in 2016 is listed here . That US Navy site can be configured for various places and years from this interface. Then you can look up various Anytown, USA locations. This will only precisely work for the game if the designers cared about modeling the real world with respect to daylight duration in either the current decade or perhaps the decade of the setting of the game in question. I'm not sure but I think that for mid lattitudes the drift in ~50 years time is fairly small, and perhaps you can ignore year for game-estimation purposes. SemanticMantis (talk) 23:30, 13 June 2016 (UTC)
 * In case there's some confusion San Andreas in Grand Theft Auto was never presented as San Andreas, California but instead as a place containing parts of something similar to California and Las Vegas. In the specific case of Grand Theft Auto: San Andreas, it was an island (I don't think it was mentioned as an island but it was an island in game) containing 3 cities fairly loosely based on Los Angeles, San Francisco, and Las Vegas. See Grand Theft Auto (series) for more. Nil Einne (talk) 14:17, 14 June 2016 (UTC)

I believe that day and night always had the same duration in GTA:VC & SA, regardless of how many days had passed in the game. However, there was (at least in GTA:SA) a days passed counter in the stats. If you measure different lengths of day/night on different days and you know how many days have passed between measurements, I think 2-3 measurements should be enough to determine latitude and day of year. 78.0.238.197 (talk) 21:36, 16 June 2016 (UTC)


 * How many degrees above the horizon can the Sun reach? What time is sunrise? What time is sunset? How many degrees north or south of due west does the Sun set? (due south or north being the Sun's direction halfway between sunrise time and sunset time, if the game says otherwise then they screwed up). Sagittarian Milky Way (talk) 22:54, 16 June 2016 (UTC)