Wikipedia:Reference desk/Archives/Science/2013 June 1

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June 1

what's the species here? it's White flowered shrub

At wildcat canyon regional park

mystery white flowers and shrub

— Preceding unsigned comment added by 66.87.69.221 (talk) 01:54, 1 June 2013 (UTC)

The picture is pretty badly out of focus, but I believe that's poison hemlock. It's very common in the California hills. If "Wildcat canyon regional park" is Wildcat Canyon Regional Park, I'm pretty confident of the identification, as I have hiked there dozens of times. Looie496 (talk) 03:06, 1 June 2013 (UTC)

Is there really a need for "poison" to be prefixed to hemlock? Does "only-makes-you-feel-a-little-bit-queasy-for-about-a-day hemlock" exist? Roger (Dodger67) (talk) 11:26, 1 June 2013 (UTC)

"Hemlock" is also a type of coniferous tree (genus Tsuga), or water hemlock, which curiously is even more poisonous than poison hemlock. But more to the point, the common name of the plant, at least in this vicinity, is the full phrase "poison hemlock". Looie496 (talk) 13:48, 1 June 2013 (UTC)

Just be happy they are not giant hogwarts. μηδείς (talk) 16:20, 1 June 2013 (UTC)

See Tsuga, a genus of trees known as "hemlock"; it took me a long time to figure out how Socrates got poisoned by a conifer tree. Nyttend (talk) 17:17, 1 June 2013 (UTC)

It is very similar to Anthriscus sylvestris or "Cow Parsley" which our article says is "an invasive species in many areas of the United States". Alansplodge (talk) 21:54, 1 June 2013 (UTC)

Reptile Identification - NT Australia

Took these mid last year, probably wouldn't take long to identify if I had field guide... seems like two of the skinks might be the same, and as many as three of the dragons might be different phases of the same species? -- Benjamint 06:40, 1 June 2013 (UTC)

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• What nice pictures, these and the gecki. Geckoi?

Either geckos or geckoes. Benjamint, you might try posting with links to your questions at the Amphibians and Reptiles project’s Talk page.—Odysseus1479 00:30, 5 June 2013 (UTC)

Hi benjamint444, I identified 5 as Diporiphora magna. Goodshort (talk) 12:29, 15 December 2013 (UTC) (from fr.wiki and Commons)

Gabapentin

Can the above drug cause death if taken in sufficient amounts?Windmill50 (talk) 07:52, 1 June 2013 (UTC)

Avoiding medical advice, drugs have an LD50. Plasmic Physics (talk) 07:56, 1 June 2013 (UTC)

To save any of us going anywhere near giving medical advice, which we cannot do, I suggest you simply look at our Gabapentin article, and Google beyond that. Seems to be plenty of material out there. HiLo48 (talk) 07:58, 1 June 2013 (UTC)

The toxicity seems to be very low. PMID 21554310 says that there is only one known fatality caused by gabapentin overdose, and PMID 8681309 says that in rats the lethal dose (LD50) is above 2 grams per kilogram. If that number carries over to humans, a human adult would have to consume the better part of a cup of the pure drug to be in serious danger. Looie496 (talk) 14:03, 1 June 2013 (UTC)

Effect of spin on bounce

This is prompted by commentary on a cricket match, and assumes a cricket ball of normal roughness being bowled on a pitch of normal roughness, with no batsman. First, the ball is bowled with no spin, so it lands partway down the pitch and bounces to some maximum height at some further distance. Second, the ball is bowled with the same speed and trajectory but has appreciable topspin - ignoring air resistance, the ball will land at the same spot, but what happens thereafter? I'd guess that its forward velocity will increase but it will bounce to the same maximum height, so this will be further on than before and (given that in reality a batsman would be in place) the bounce will appear to be less. Third, the ball is bowled with the same speed and trajectory but has appreciable backspin. I'd guess that in this case the ball will appear to bounce more than in the first one, in that the point of maximum height after first landing will be closer to the bowler. So, from the batsman's view, topspin gives low bounce and backspin gives high bounce. However, the commentator claimed the exact opposite. Which would it be? 86.139.121.71 (talk) 10:37, 1 June 2013 (UTC)

I agree with your intuition but empirical observations are best in a complex situation where the result of spin will depend on many details (relative influences of wind resistance on the ball, the friction between ball and pitch, etc). I have scant knowledge of cricket, but we have articles that address your question. For example, Topspinner notes that the downward aerodynamic force imparted by topspin results in earlier contact with the ground and a higher bounce. Given that, it's not hard to extrapolate that backspin might extend the flight, resulting in a shallower angle at first contact and a lower bounce. Hope this helps. -- Scray (talk) 13:10, 1 June 2013 (UTC)

See topspin, backspin, and Magnus effect. SemanticMantis (talk) 14:32, 1 June 2013 (UTC)

Thanks. From this extract from the topspinner article Tactically, a bowler will bowl topspinners to draw a batsman forward before using the dip and extra bounce to deceive them. However, on an underprepared soft wicket, the spin on the ball may actually cause it to grip and shoot through low, it would seem that both effects on bounce can occur, depending on the nature of the ground surface. It seems reasonable that backspin could react in either way, too, depending on the same thing. 86.139.121.71 (talk) 18:24, 1 June 2013 (UTC)

Reptile Identification - Cameron's corner, Eastern(ish)/Central Australia

a couple more gecko's needing ident. these ones were taken in October within a few hundred km of Cameron's corner. A couple seem to be Gehyra spp. but I don't really know what to look for when identifying these guys. Benjamint 11:18, 1 June 2013 (UTC)

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No idea, but try this GECKOS INDEX. Alansplodge (talk) 08:25, 2 June 2013 (UTC)

Yeah I tried that site already for the geckos in my post above, it seems like a comprehensive list of species in that area but not particularly helpful elsewhere unfortunately -- benjamint

The element which can form the largest number of covalent bonds

Hi,
Till recently I thought that elements can create only between 0-4 covalent bonds.
Can someone give me the element which can create the largest amount of covalent bond? Exx8 (talk) 11:11, 1 June 2013 (UTC)

Osmium can form up to eight bonds. Plasmic Physics (talk) 11:13, 1 June 2013 (UTC)

Scratch that, rhenium can form up to nine bonds in the ion nonahydridorhenate. Plasmic Physics (talk) 11:15, 1 June 2013 (UTC)

The pattern you note is only valid for the main block elements, and only generally so. Some main block elements can also exceed a valence of four, and some don't reach their assigned group valence under ordinary conditions. Chlorine can reach a valence of seven, despite being assigned a group valence of one, while thallium usually can only reach a valence of one, despite being assigned a group valence of three. Plasmic Physics (talk) 11:39, 1 June 2013 (UTC)

physics - heat project topic

if a can (soft drink can) completely filled with ink and boiling hot water is poured in a glass bowl containing ice cold water then give observations and give a scientific reason for the observations. — Preceding unsigned comment added by 117.197.57.78 (talk) 15:46, 1 June 2013 (UTC)

Have you tried it? What happens? Looie496 (talk) 16:53, 1 June 2013 (UTC)

Please do your own homework.

Welcome to Wikipedia. Your question appears to be a homework question. I apologize if this is a misinterpretation, but it is our aim here not to do people's homework for them, but to merely aid them in doing it themselves. Letting someone else do your homework does not help you learn nearly as much as doing it yourself. Please attempt to solve the problem or answer the question yourself first. If you need help with a specific part of your homework, feel free to tell us where you are stuck and ask for help. If you need help grasping the concept of a problem, by all means let us know. Red Act (talk) 19:31, 1 June 2013 (UTC)

Colubrid snake acting a little rattlesnake-like

I just chased a snake out of my garage; it seemed at first like a common (non-venomous) colubrid ... entirely black with very little variation, about a meter long, and the head didn't seem particularly large or triangular. But when I waved a rake at it, instead of running away, it lunged at the rake ... and then sat in the corner and shook the end of its tail for all it's worth. I haven't seen that behavior before except in rattlesnakes, but I'm not a snake guy. What are the odds the snake is venomous, despite the normal-looking head? - Dank (push to talk) 15:57, 1 June 2013 (UTC)

Can you tell us the location? It was just mentioned here recently that tail shaking in agitated snakes is common, as it is the only available limb. μηδείς (talk) 16:14, 1 June 2013 (UTC)

Central North Carolina, US. Good to hear about the tail-shaking! - Dank (push to talk) 16:41, 1 June 2013 (UTC)

I live near you (I believe we've met once or twice). Long black NC snakes are usually Rat snakes, likely Pantherophis alleghaniensis. They're harmless but skittish if you corner them. I've had them rear up and lunge at me before running away when poked (accidentally) with garden rakes. They like to burrow under mulch and pine straw. Actually quite good snakes to have around as they eat rodents (as the name implies), which like to poop in the corner of my crawlspace and garage. Rat snakes don't do that, but do eat the things that do. --Jayron32 17:28, 1 June 2013 (UTC)

King snakes are often black, known to shake their tales, and would be local and are more aggressive than some other snakes. Since they eat other snakes you may want to leave them alone if you are not snake-fond. μηδείς (talk) 17:30, 1 June 2013 (UTC)

Could be that too. King snakes, like rat snakes, have a large number of species and variations, and there are black king snakes and black rat snakes that look nearly identical. Either way, it isn't harmful. Also, a similar google search shows that rat snakes ALSO shake their tails when startled, so given the information above, I'm not sure we could tell the difference. --Jayron32 17:35, 1 June 2013 (UTC)

Thanks much guys (and yes, hi again Jayron!). It sounds like it could be either, but if forced to guess, I'd guess it's something in the king snake genus ... I've seen plenty of eastern rat snakes around here, and this seemed more aggressive and into tail-shaking ... and a few weeks ago, I saw a similar snake chasing and fighting a similar snake ... I assumed it was a territorial fight, now I think it was a hungry king snake. - Dank (push to talk) 18:37, 1 June 2013 (UTC)

I’ve seen bull snakes behave like that, in the badlands of southern Alberta. It was typical of the smaller or younger ones when disturbed; the big ones would more often head for cover or find an ‘anchor’ to coil themselves around. And no, they’re not venomous either, although I gather they do sometimes eat rattlers.—Odysseus1479 03:09, 4 June 2013 (UTC)

If one testicle is larger than the other,what should the effect on the body?

Another question about testicle.If one testicle is larger than the other,what should the effect on the body? — Preceding unsigned comment added by Titunsam (talk • contribs) 18:39, 1 June 2013 (UTC)

Normally no affect at all, in fact difference in size and height is more common than exact congruence. Dbfirs 19:06, 1 June 2013 (UTC)

This topic was studied in great detail by the famous Asian scientist, Dr. Won Hong Lo. ←Baseball Bugs ^{What's up, Doc?} carrots→ 20:49, 1 June 2013 (UTC)

Be serious, now, Bugs. Males walking long distances in unmarked landscape tend to walk in a circle to the right or left depending on which testicle is larger. μηδείς (talk) 21:02, 1 June 2013 (UTC)

Is the the result of some serious hands-on research? HiLo48 (talk) 23:39, 1 June 2013 (UTC)

This site, among many others out there, states that it is normal for a man's testicles to be different sizes. - Karenjc 21:45, 1 June 2013 (UTC)

One of the more interesting pieces of research on this topic is Scrotal asymmetry in man and in ancient sculpture, which won its author, Chris McManus, an Ig Nobel Prize in Medicine in 2002. The report states that, in most human males, the right testicle is higher and larger than the left. However, in Greek sculptures, the right testicle is indeed depicted as the higher, but it's the left testicle that's shown larger. The theory is that the Greeks assumed that gravity would act to pull the larger testicle further down. Mind you, they apparently also believed that the testes' main function was to act as tensioners for the vocal chords - naturally enough, when you think about it, since small boys have small testes and high-pitched voices, but as the testicles grow and descend, the voice becomes deeper. - Cucumber Mike (talk) 22:28, 1 June 2013 (UTC)

How far from Humans evolutionarily to *not* have just two chest nipples?

How far away from Humans evolutionarily do you have to get to get animals that have something other than two chest nipples? Do all Primates have just two chest nipples, all Apes, All Great Apes? I believe that I was told that Humans are unique in that the breast tissue is actually disconnected across the sternum.Naraht (talk) 22:07, 1 June 2013 (UTC)

AFAIK, all primates have two mammary glands; which means you'd need to go one clade up from the Primates order, which would be the Euarchontoglires Superorder. Both Rodents and Lagomorphs (Rabbits, et. al.) are part of that superorder, and they have more than two such nipples. Since those are all co-equal members of the Euarchontoglires superorder, all of those would be equally "distant" from humans, evolutionarily speaking, so "non-Primate Euarchontoglires" is your grouping that meets your criteria. --Jayron32 22:57, 1 June 2013 (UTC)

(ec)Lemurs are primates, at least in most classifications; our articles on Ruffed lemur and ring-tailed lemur describe multiple pairs of mammary glands. Nimur (talk) 01:42, 2 June 2013 (UTC)

In that case, the infraorder Simian is the clade in question, since the Simian clade is basically "primates minus lemurs and tarsiers". I think Tarsiers are closer in relation to humans than lemurs are, however, do tarsiers have multiple pairs? --Jayron32 04:31, 2 June 2013 (UTC)

Not far at all. Supernumerary nipples are surprisingly common in humans. I've seen several cases myself, especially when I was giving free EKGs during free community health screening programs. According to our article, celebrities with extra nipples include Zac Efron, Harry Styles and Mark Wahlberg. Dominus Vobisdu (talk) 01:36, 2 June 2013 (UTC)

And Chandler Bing. RNealK (talk) 03:27, 2 June 2013 (UTC)

"That's not a nipple, that's a nubbin !". StuRat (talk) 04:22, 2 June 2013 (UTC)

"Apelike they were, he said, and simian; Instead of normal men and wimian": From 18:05. -- Jack of Oz ^[Talk] 05:22, 2 June 2013 (UTC)

Wow. Amazing what features go unnoticed in familiar landscapes! Putting in some hard work, I find [1] (erm, sorry, I just left out the other four images I found due to Wikipedia's excessive copyright paranoia, but I assure you an images.bing search for Zac Efron nipple will not leave you disappointed. But the appearance is remarkably subtle!) Wnt (talk) 14:10, 2 June 2013 (UTC)