Wikipedia:Reference desk/Archives/Science/2016 October 21

= October 21 =

Two questions after watching Disney's Tarzan...
Naraht (talk) 04:58, 21 October 2016 (UTC)
 * 1) What mammals other than Man reach sexual maturity and/or full growth after age twelve? Elephants?
 * 2) Is there a significant difference among the milk of the great apes (compared to the difference between Human milk and Cow Milk?
 * For 1, suggests female Asian elephants and some male Asian elephants achieve sexual maturity after twelve. (But some humans do achieve sexual maturity before 12.) African elephants   seem to often be before 12 years. I'm not sure how reliable this source is  , but I believe it's correct that elephants are not fully grown at this stage and therefore male elephants at least rarely mate at this age. Nil Einne (talk) 08:33, 21 October 2016 (UTC)
 * My guess was the blue whale but "The blue whale reaches sexual maturity at around 10 years of age."  Alansplodge (talk) 11:04, 21 October 2016 (UTC)
 * Male sperm whales "become sexually mature at 18 years" according to the article, or "between 18–21 years" according to the Australian Department of the Environment and Energy for instance. For female sperm whales the corresponding ages are given as "9" / "between 7–13". ---Sluzzelin talk  12:35, 21 October 2016 (UTC)
 * For 2, The constantly protruding breasts of the adult human female differ from the mammary glands of other Primates that protrude only while actually filling with milk, and are presumably the result of evolutionary sexual preference by males, see Mammary gland. In this article studies on the milk of primates, especially in comparison with human milk, are reviewed. This article reviews primate lactation biology and milk synthesis to identify the derived and ancestral features of primate milks. This report elucidates the structures of free milk oligosaccharides so that they can be related to glycan function in different primates. AllBestFaith (talk) 13:13, 21 October 2016 (UTC)
 * This is a sidetrack, but it's useful in pointing out the distinction between breast and mammary gland. The former article currently says "In females, it serves as the mammary gland..." which makes me wince, not just because men can (rarely) lactate effectively, but because the breast contains fatty tissue that is not part of the gland.  And indeed, the human breast is specifically designed to stand out on its own, without lactation activity!  Not entirely easy to find a good source to cite for this distinction though. Wnt (talk) 17:27, 22 October 2016 (UTC)
 * Regardless of how much or how little a woman has "up front", the breasts will typically expand during the time period of lactation. Hence the need for a Nursing bra. ←Baseball Bugs What's up, Doc? carrots→ 19:37, 24 October 2016 (UTC)
 * Quibble,, but human breasts aren't specifically designed to stand out as they aren't designed at all; they have evolved to stand out. EdChem (talk) 23:52, 24 October 2016 (UTC)
 * Forsooth this is a well-worn and erudite point to make, and yet I indulged said trolling because I doubt the philosophy behind it. Evolution is, of course, a fact; but I feel it does not preclude design.  Were this a random world, it would in all likelihood be barren rock, and yet, we are here, though the power of the anthropic principle, at least.  And breasts are, by all expectation, in large part the product of the sexual selection of so many randy boys who have, bit by bit, hallucinated their fondest dreams into a glorious and living reality.  If the power of our consciousness can produce breasts from barren moonscapes through such scientifically valid means, I think perhaps we should not discount that the design of the universe may have been influenced, in part, by some other conscious mechanism so that this type of beauty would exist today.  We don't really know why we live in the universe we do, or what makes it real as opposed to every other imagining that might be encoded in some transcendental number or other.  Why presume it is all calculated mathematically from a random and boring point in the past that no one has seen, rather than being calculated backwards from its destiny to produce some specific and wonderful scene in the future?  And so, whether for the lesser reasons above or for the greater reason of some divine plan for humanity, I choose to regard breasts as being designed, even though, admittedly, much of that belief is unfalsifiable and scientifically meaningless.  If it is meaningless, so is the opposite. Wnt (talk) 01:23, 25 October 2016 (UTC)
 * This is sort of similar to how E. O. Wilson, one of the greatest living biologists, has no problems talking about "the creation". I don't think he ever talks about any creator, but there isn't really any scientific quibble with saying that all this is a creation, insofar as our best understanding is that it was not this way long ago. SemanticMantis (talk) 14:45, 25 October 2016 (UTC)

What makes wasabi difficult to cultivate?
My friend told me today most wasabi comes from horseradish - and the Wikipedia article backs this up. This is attributed to the wasabi's cost and rarity, which is due to difficulty in its cultivation...but the article does not provide reasons why. Thus, the header question. I would appreciate any insight into this question. Thank you! Rotideypoc41352 (talk) 20:17, 21 October 2016 (UTC)
 * http://www.thewasabicompany.co.uk/wasabi-plants/wasabi-plant are the people to ask. Seems that it has been something of of an occult art until recently, but they claim to have made it practical, both for their commercial production, and for home-grown. Andy Dingley (talk) 20:38, 21 October 2016 (UTC)


 * Agree with Rotideypoc41352 that this article is lacking. As to the cultivation bit, that is easy to answer. Both Wasabi and Horseradish need the right soil conditions in order to provide an economic viable crop yield. Most farm land doesn't provide those ideal conditions regardless of how much fertilizer etc one spreads.. Just as trying to cultivate watercress in the Sahara Desert is very difficult too. I have grown horseradish but it need to be grown in a corner of the garden were the soil is always damp and with a low  pH.--Aspro (talk) 21:04, 21 October 2016 (UTC)


 * Talking of damp... Looking at File:Izu city, Ikadaba, Wasabi fields 20111002 C.jpg have you noticed that the commercial plantation depicted in that image is on a stream bed. IE., very moist  with a low pH. Opposite example: One can't convince a rhododendron to grow in most of Kent as the soil doesn't suit them (pH too high) . Rhododendron.Org --Aspro (talk) 21:32, 21 October 2016 (UTC)


 * I have visited a wasabi farm in Japan. Wasabi is typically grown in running water such as a stream bed with a constant water temperature of between 12°C (54°F) and 14°C (57°F). Anything outside of 8°C (46°F) and 20°C (70°F) and the plants will die. --Guy Macon (talk) 21:49, 21 October 2016 (UTC)


 * Exactly. So, coming back to the OP's question. Rather than the article stating that  “Wasabi is difficult to cultivate” it should read something like  “Wasabi favours  growing conditions which restricts its wide cultivation. The resulting inability to fully satisfy commercial demand, thus makes it quite expensive”. Or something along those lines – with some ref's.  Should this discussion not be now  transferred to this articles talk page? How does one do that?--Aspro (talk) 22:38, 21 October 2016 (UTC)
 * It probably should not be taken to the Talk page. Talk pages are for discussing what should be in the article.  This seems to be a general question about production of wasabi.  If the OP or other editor wants to question whether the article should contain content about the production, that should be on the Talk page. DrChrissy (talk) 22:50, 21 October 2016 (UTC)


 * The OP's question has alerted us, that this article is deficient enough to warrant him asking this question. Why he didn’t post this on the article's talk page I don't know. Yet, a better, explanation should be in this article – which I don't think the OP would disagree with – otherwise he would not have needed to ask – in the first place – and where do we have those discussions if not on the talk page? --Aspro (talk) 23:26, 21 October 2016 (UTC)


 * I guess it depends on the motivation of the OP for posting the question. If they intend to edit the article with information on production, yes, the question should have been posed at the Talk page.  If the OP was simply wanting to know why there are problems producing wasabi, then this is probably the correct place.  I have to admit, I have not even read the wasabi article so I did not know this information was missing.  I do not feel strongly about this at all so please feel free to move this thread to the Talk page if you wish - I will certainly not challenge that. DrChrissy (talk) 23:35, 21 October 2016 (UTC)


 * My feeling (per Aspro) is that if an OP asks a question on a RefDesk about a subject whose article they have linked (and presumably therefore read, as is explicitly stated in this case), it's prima facie evidence that the article is probably lacking and/or unclear in some fashion (assuming no trolling, which is certainly not the case with Rotideypoc41352's query).
 * While no volunteer on the RDs is thereby obliged to go and improve the article, it's a clear signal that improvement is desirable, and potential article editors are free to continue on the article's talk page, or one of them could just boldly go ahead and fettle it.
 * This doesn't mean that the OP wasn't right to ask at the RD in the first place: for most users (IP or signed up), the RDs are for supplying wanted information – that some of us may also utilise RD queries as a steer to improving articles is an added benefit, not a rival purpose. {The poster formerly known as 87.81.230.195} 90.197.27.88 (talk) 02:37, 22 October 2016 (UTC)
 * Whenever I see a question like the OP's asked on an article talk page, I take it as implicit that it is saying "This article is deficient. What information do we need to add to fix this?"  However, I quite often see people get told off for asking such questions ("The talk page is for discussing improvements to the article.  If you have general questions about the subject go to the Reference Desk") if they don't spell that out.  Iapetus (talk) 09:13, 24 October 2016 (UTC)
 * There are some very well informed editors on the Ref page who may be able to offer advice on articles they don't watch. I guess the "most correct" approach is to ask the question on the article's Talk page first, and if no answers are forthcoming, bring it here.  However, an editor should never be told off - this ref page is one of the friendliest places on WP - let's keep it that way. DrChrissy (talk) 15:44, 24 October 2016 (UTC)


 * As other editors also see the need for a clarification, Have edited the article the using Guy Macon refinances thus: Wasabi. Does this now cut the mustard ?--Aspro (talk) 19:43, 25 October 2016 (UTC)
 * I see what you did there. Nice one! 22:31, 25 October 2016 (UTC)