Talk:Phyllotaxis

message: Here's what the article says:
A repeating spiral can be represented by a fraction describing the angle of windings leaf per leaf. Alternate leaves will have an angle of 1/2 of a full rotation. In beech and hazel the angle is 1/3, in oak and apricot it is 2/5, in poplar and pear it is 3/8, and in willow and almond the angle is 5/13.[2] The numerator and denominator normally consist of a Fibonacci number and its second successor. The number of leaves is sometimes called rank, in the case of simple Fibonacci ratios, because the leaves line up in vertical rows. With larger Fibonacci pairs, the ratio approaches phi and the pattern becomes complex and non-repeating.
If we try a few examples, we can see that the ratio does not approach phi. For example, 13/5 = 2.6, while phi is about 1.618. Or we can try fib(30)/fib(28) = 832040/317811 = 2.6180339887543225. Clearly this is not converging on phi.
If you want numbers that approximate phi, you can try a Fibonacci number and its successor. For example, fib(30)/fib(29) = 832040 / 514229 = 1.61803398874820362134. Therefore, the article appears to be incorrectly claiming that dividing a Fibonacci number into that number's second successor will approximate phi. In fact, to approximate phi you should divide a Fibonacci number into its successor, not its second successor. 13:09, 17 October 2008 (UTC)
replies: text: lofthouse, his point was that it DOESN'T converge to phi, when you use a Fibonacci number and its SECOND successor.  And he's absolutely right.  Uporządnicki (talk) 12:53, 11 May 2012 (UTC)

text: Just a quick look-and-think suggests to me that the sequence might be converging on the square of phi.  That comes to about 2.617924.  Uporządnicki (talk) 13:58, 10 May 2012 (UTC)
replies: text: Without going into general details, the examples given necessarily converge to the square of phi, because the numerators and denominators given are  alternate Fibonacci numbers (1,1,2,3,5,8,13...) Note that phi^(n+1)=phi^(n-1)+phi^(n), so that phi^2=phi^0 + phi^1 (2.61803... = 1 + 1.61803...). But without explanatory details concerning the underlying mechanisms, that amounts to numerology. Maybe someone with access to some of the more recent publications could supply some helpful material? JonRichfield (talk) 09:12, 11 May 2012 (UTC)
thread_title:  Phi reference wrong 

message: Under the section Repeating Spiral, discussing successive plant leaves along a branch spiraling until a leaf finally lines up with the first leaf in consideration, and the pattern repeats, it says "With larger Fibonacci pairs, the pattern becomes complex and non-repeating."
I'm not an expert--neither a mathematician or a botanist.  But it seems to me that that might be true only in practical terms, not mathematical.  When I think it through, it seems to me that mathematically, with ANY Fibonacci pair "m/n", after "n" leaves, the spiral will get back to its starting point--having gone around the branch "m" times. So it seems to me that if "[w]ith larger Fibonacci pairs, the pattern becomes complex and non-repeating," this would only be due to the practical point that with larger Fibonacci pairs, you'll never find a branch with enough successive leaves.
If I'm wrong, I'd be grateful if someone could explain it to this layperson.  But if I'm right, I think the statement in the article could do with clarification.  Uporządnicki (talk) 13:28, 10 May 2012 (UTC)
thread_title:  Larger Fibonacci pairs--really non-repeating? 

message: The article says that Alternate leaves will have an angle of 1/2 of a full rotation. But this assertion is not qualified at all. If it applies to a specific example, that is not mentioned. If this is a general rule, it is not explained further, and the examples that follow (which are specific) give different rotation values. Aboctok (talk) 23:48, 22 June 2012 (UTC)
replies: text: Good catch! I've changed it to "Alternate distichous leaves will have an angle of 1/2 of a full rotation." Sminthopsis84 (talk) 01:18, 23 June 2012 (UTC)
thread_title:  Repeating spiral section 

message: Phyllotaxy Towers are kind of Phyllotactic Architecture.  — Preceding unsigned comment added by 2.187.98.165 (talk) 11:15, 4 November 2012 (UTC)
replies: text: This is listed in the See also section. Where that was recently added is a section about plants, not clearly written, but probably intended to refer to "plant architecture", a sub-discipline of botany. Sminthopsis84 (talk) 14:55, 4 November 2012 (UTC)
replies: text:  The article on P. Towers was recently deleted at AfD. I believe the references there would be useful in a new article on either Biomimetic architecture or Phyllotactic architecture, to cover (actual) domes as well as (putative) towers. There would then be a place for links in either direction with Phyllotaxis. There could also be a place for a properly-cited paragraph here about the application of phyllotaxis to the architecture of buildings. Chiswick Chap (talk) 08:24, 18 November 2012 (UTC)

text: Admins can see deleted content, and if you request it I can make a user space copy of the article.--Salix (talk): 13:56, 18 November 2012 (UTC)

text: There is the germ of an article here, probably along the line of biomimetic architecture. The problem with the delete article was that there is very little literature on the subject, indeed the only place the term is used is in the authors own thesis. biomimetic architecture has a much greater amount of supporting literature and would not be at risk of deletion.--Salix (talk): 14:07, 18 November 2012 (UTC)
replies: text: Thanks. I don't think I have time right now to be the prime builder of such an article, but could help out if someone else wants to take the lead. Sminthopsis84 (talk) 14:17, 18 November 2012 (UTC)
thread_title:  Phyllotactic Architecture 

message: * URBAN CACTUS HIGH-RISE
* ‘Mangal City’ Skyscrapers
* Phyllotaxy Towers  — Preceding unsigned comment added by 2.187.120.8 (talk) 07:28, 19 January 2013 (UTC)
thread_title:  Case Studies 

message: * Star Cage
* phaselab
* 
* MathWorld
* math.smith
* Phyllotaxis: The Fibonacci Sequence in Nature
* Twig and Leaf Phyllotaxy
* Phyllotaxis Spirals in 3D
Heres the links from that article. Some are enough to support a section on Phyllotactic art or Phyllotactic in construction.--Salix (talk): 10:10, 18 November 2012 (UTC)
thread_title:  External links on Phyllotaxy 

message: Thank you Chiswick Chap and Salix for explaining what happened, I was starting to think that I'd left this page with a red link in See also! Is it really the case that once a page has been deleted there is no way to recover the text that was there? In any case, this is so discouraging that I don't intend to put any effort into researching the topic in order to create a page about it that would just be attacked once again by deletionist forces. Sminthopsis84 (talk) 13:48, 18 November 2012 (UTC)
replies: text: Admins can see deleted content, and if you request it I can make a user space copy of the article.--Salix (talk): 13:56, 18 November 2012 (UTC)

text: There is the germ of an article here, probably along the line of biomimetic architecture. The problem with the delete article was that there is very little literature on the subject, indeed the only place the term is used is in the authors own thesis. biomimetic architecture has a much greater amount of supporting literature and would not be at risk of deletion.--Salix (talk): 14:07, 18 November 2012 (UTC)
replies: text: Thanks. I don't think I have time right now to be the prime builder of such an article, but could help out if someone else wants to take the lead. Sminthopsis84 (talk) 14:17, 18 November 2012 (UTC)
thread_title: Thank you for explaining here

message: Mention which pattern appeared on earliest plants, etc. Jidanni (talk) 07:53, 29 September 2020 (UTC)
thread_title:  Evolution