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Omnipresent phyllotaxis The essence of phyllotaxis consists in screw arrangement of leafs on plant stems (branches on trees, petals in racemes etc.). In the phyllotaxis phenomenon the more complicated concepts of symmetry, in particular, the concept of the "screw axis of a symmetry", is used. Botanists established that the phyllotaxis fraction from the sequence of (1) are characteristic for different plants. www.goldenmuseum.com /0604Phillotaxis_engl.html   (882 words)

Section 5: Phyllotaxis   (Site not responding. Last check: 2007-10-27) Phyllotaxis or phyllotaxy refers to the arrangement of leaves along a stem. Phyllotaxis originates at the shoot apex where the directions for growth are genetically programmed in the meristematic tissues. Spiral phyllotaxy is the classification of leaf arrangement where by one leaf primordium is produced at a time by the apical meristem. botit.botany.wisc.edu /courses/structure_cd/labs/B5/5.htm   (532 words)

deodands | Fibonacci phyllotaxis The subsequent literature of phyllotaxis is substantial, and I have been primarily guided by the various surveys in Jean and Barabe (1998) for this section. Some of the subsequent studies of phyllotaxis concentrated on, and gave more rigorous mathematical theories of, the 'static'; phyllotactic problem of the classification of lattices, and, for example, the relationship between the divergence angle and the visible opposed parastichies (Adler et al (1997), Jean (1994)). It may be relevant that quite a large number of the archive sheets (unpublished in Saunders (1992)) are concerned with the dynamics and the stability of lattices. www.swintons.net /deodands/archives/cat_fibonacci_phyllotaxis.html   (3661 words)

Phyllotaxis - Cambridge University Press Phyllotaxis, the study of the patterns determined by leaves, petals, and other organs of plants, raises some of the deepest questions of plant morphogenesis. In this book, the many facets of phyllotaxis are dealt with in an integrated manner for the first time. The author describes a unified concept of phyllotaxis, and presents a mathematical model of plant growth based on experimental, anatomical, cellular, physiological and palaeontological observations. www.cup.cam.ac.uk /catalogue/catalogue.asp?isbn=0521404827   (330 words)

deodands: Fibonacci Phyllotaxis Phyllotaxis means here the arrangement of structures, such as leaves or florets, in plants. According to Adler et al (1997) the first to explicitly recognise that Fibonacci numbers were involved in phyllotaxis were Schimper (1831) and Braun (1831). Another excellent example of Fibonacci phyllotaxis, very well known to Turing, is the fir cone. www.swintons.net /deodands/archives/000088.html   (571 words)

Buffalo Museum of Science - Principia Botanica - Analysis of Phyllotaxis The analysis of biological symmetry which utilizes essentially geometrical premises is similar in many respects to the analysis of plant morphology which begins with the given categories of leaf, stem and root or biogeography which begins with casual migrations. This tendency is responsible for the establishment, at the level of coelocanthid fishes, of the morphogenetic premise which led for example, to the five fingers of Homo and for the reduction of the ancestral strobile around five sectors of growth which led to modern pentamerous flowers. The genetic spiral, described by the developmental sequence of leaf primordial, is often assumed to have special significance for phyllotaxis. www.sciencebuff.org /principia_botanica_analysis_of_phyllotaxis.php   (1244 words)

Twig and Leaf Phyllotaxy The arrangement is such that drops from the first leaf fall on the fourth leaf in some cases and on the sixth in others." This observation call attention to the fascinating, naturally occurring mathematical phenomena: leaf phyllotaxy and the Fibonacci numbers. We can conclude that phyllotaxy is another means by which to identify woody plants in the field, especially in winter. Knowing the phyllotaxy of woody plants adds to the fun of field trips in the winter. www.ct-botanical-society.org /newsletter/phyllotaxy.html   (909 words)

KWIATKOWSKA, DOROTA. Patterns associated with phyllotaxis are: pseudowhorls; primary vasculature; and wing pattern. Number of leaves in a pseudowhorl depends on the quality of phyllotaxis, but also on the relation of leaf primordia size to the size of an apex dome, i.e. Another pattern closely related both to the quality of phyllotaxis and to primordia packing is the pattern of vascular sympodia. www.ou.edu /cas/botany-micro/bsa-abst/section2/abstracts/11.shtml   (310 words)

Geometrical relationships specifying the phyllotactic pattern of aquatic plants -- Kelly and Cooke 90 (8): 1131 -- ... The primary principle relates the sites of primordial initiation to the overall phyllotaxis, i.e., primordia arising on the apical dome are often positioned in spiral arrangements, while primordia arising on the subtending axis are arranged in whorled patterns. Different spiral phyllotaxes are illustrated by the apical meristems of Brassica oleracea, Linum usitatissimum, and Helianthus annuus, which show that the ratio of the size of young primordia to the apical dome is inversely correlated with the magnitude of the Fibonacci numbers characterizing these phyllotaxes. Jean R. 1994 Phyllotaxis, a systematic study in plant morphogenesis. www.amjbot.org /cgi/content/full/90/8/1131   (6904 words)

About Intro The number of visible spirals (parastichies) in spiral arrangements are most often Fibonacci numbers (1, 1, 2, 3, 5, 8, 13, 21...) and the angle between successive leaves is close to the Golden Angle - about 137.5 degrees. This frequent type of pattern is called Fibonacci phyllotaxis. Phyllotaxis has affinities to other pattern formation mechanisms where many simple agents interact with simple rules. maven.smith.edu /~phyllo/About/index.html   (224 words)

SYMMETRY IN PLANTS The first two parts concern data collecting, pattern recognition and pattern generation to which students of phyllotaxis are well accustomed. The third part is devoted to the problem of origins of phyllotactic patterns, giving the field of phyllotaxis the universality it requires to be fully understood. This book on mathematical and biological phyllotaxis is the first collective book ever. www.worldscibooks.com /lifesci/3063.html   (430 words)

A plausible model of phyllotaxis -- Smith et al. 103 (5): 1301 Data Supplement - HTML Page - index.htslp -- Proceedings ... Starting with the parameter values for the spiral phyllotaxis simulation (column Spiral in Table 1), selected equations or parameters of the model were changed, and simulations were run again to determine whether spiral phyllotaxis could be maintained. The spiral phyllotaxis was maintained after reducing the transport coefficient T' from 22.5 to 19.0, the primordium differentiation threshold Th from 7.5 to 7.0, and the peripheral zone size from 2.9 to 2.57 (simulation SA3 in Table 3). Spiral phyllotaxis was maintained after increasing diffusion coefficient D from 4.0 to 4.5 and decreasing transport coefficient T from 22.5 to 22 (simulation SA4 in Table 3), but the simulation was very sensitive to parameter values. www.pnas.org /cgi/content/full/0510457103/DC1   (1932 words)

Phyllotaxis: Helical arrangement of leaves and staggered dots on shells - two corresponding patterns — Max Planck ... The regular initiation of leaf (or seed) primordia behind the tip of a growing shoot, called phyllotaxis, seems to have nothing in common with any pattern on sea shells, but this impression is misleading. As in shells, also on a growing shoot, new pattern elements appear in a narrow zone that shifts in the course of time due to growth. For phyllotaxis this suggest that not the previously formed leaves but some sort of memory within the leaf forming zone is responsible for the positioning of the next leaf. www.eb.tuebingen.mpg.de /dept4/meinhardt/phyllo.html   (1165 words)

Phyllotaxis Leaves, petals and other organs in plants are not arranged randomly, rather they seem to follow well-defined rules. This geometrical arrangement of organs is one of the main questions in plant morphogenesis, and the study of patterns thus produced is named phyllotaxis, from the greek phyllo (leaf) and taxis (order). The study of phyllotaxis is also relevant for other non-botanical structures, such as crystals, Mandelbrot set or proteins. coco.ccu.uniovi.es /malva/sketchbook/lssketchbook/examples/phyllotaxis/phyllotaxis.htm   (191 words)

The Fibonacci Numbers and Golden section in Nature - 2 The technical term for the study of the arrangements of leaves and of seedheads in plants is phyllotaxis. F J Richards Phyllotaxis: Its Quantitative Expression and Relation to growth in the Apex Phil. Eddy Levin has invented a wonderful golden-section measuring tool, like a pair of dividers or callipers and he has a page of examples of it in use showing the golden section on flowers, insects, leaves etc that's well worth looking at. www.mcs.surrey.ac.uk /Personal/R.Knott/Fibonacci/fibnat2.html   (2661 words)

Plant architecture -- Reinhardt and Kuhlemeier 3 (9): 846 -- EMBO Reports   (Site not responding. Last check: 2007-10-27) If the size of the meristem allows for two auxin maxima to coexist, then pairs of opposite leaves are formed, resulting in decussate phyllotaxis (I). Phyllotaxis is thought to be a multigenic trait because, although Reinhardt, D. and Kuhlemeier, C. (2001) Phyllotaxis in higher plants. emboreports.npgjournals.com /cgi/content/full/3/9/846   (3634 words)

Phyllotaxis   (Site not responding. Last check: 2007-10-27) In many cases, such as the celebrated case of the sunflower head, phyllotactic patterns involve the golden angle. I put some discssuion of the appearance of Fibonacci numbers and the golden ratio in phyllotaxis at Talk:Fibonacci number/Phyllotaxis. Some of it might be useful here once this article is fleshed out a little more. www.wwwtln.com /finance/144/phyllotaxis.html   (662 words)

Symmetry in Plants   (Site not responding. Last check: 2007-10-27) It aims at reflecting the widest possible range of ideas and researches closely related to phyllotaxis and contains 30 well illustrated chapters, four prologues and a foreword. Prologue by a Mathematicien: The Role of mathematics in phyllotaxis Plastochrone Ratio and Leaf Arc as Parameters of a Quantitative Phyllotaxis Analysis in Vascular Plants www.mi.sanu.ac.yu /vismath/sg/plant.htm   (459 words)

Auxin Regulates the Initiation and Radial Position of Plant Lateral Organs -- Reinhardt et al. 12 (4): 507 -- THE PLANT ... distichous phyllotaxis and the symmetry observed in whorled Shown are distichous phyllotaxis (B), spiral phyllotaxis (C), whorled phyllotaxis (D), and reversion from whorled to spiral phyllotaxis (E). Kirchoff, B.K. (1984) On the relationship between phyllotaxy and vasculature: A synthesis. www.plantcell.org /cgi/content/full/12/4/507   (6080 words)

Phyllotaxis - Cambridge University Press The author describes a unified concept of phyllotaxis, and presents a mathematical model of plant growth based on experimental, anatomical, cellular, physiological, and paleontological observations. The model not only provides a framework for formal analyses of botanical data, but also emphasizes the relevance of phyllotaxis to other structures, such as crystals, and proteins. Interpretation of Fujita's frequency diagrams in phyllotaxis; 7. www.cambridge.org /us/catalogue/catalogue.asp?isbn=0521404827   (254 words)

Phyllotaxis in Xanthium Shoots Altered by Gibberellic Acid -- MAKSYMOWYCH and ERICKSON 196 (4295): 1201 -- Science Phyllotaxis in Xanthium Shoots Altered by Gibberellic Acid -- MAKSYMOWYCH and ERICKSON 196 (4295): 1201 -- Science Phyllotaxis in Xanthium Shoots Altered by Gibberellic Acid Phyllotaxis in control plants displayed a 2,3 contact www.sciencemag.org /cgi/content/abstract/196/4295/1201   (292 words)

Tomato Branching&phyllotaxis   (Site not responding. Last check: 2007-10-27) The arrangement of leaves on a stem is called phyllotaxy. Tomato phyllotaxy is termed spiral because only one leaf is present at each node and each successive leaf is displaced approximately 137.5 degrees from the last. Thus a line connecting successively older leaves (leaves #1 to #5 in the figure) would make a spiral. sanangelo.tamu.edu /agronomy/tomato/branching.html   (383 words)

Disruption of a DNA Topoisomerase I Gene Affects Morphogenesis in Arabidopsis -- Takahashi et al. 14 (9): 2085 -- THE ... The genesis of phyllotaxis, which often is associated with the Disorganization of the spiral phyllotaxis in clavata (clv1, Jackson, D., and Hake, S. Control of phyllotaxy in maize by the abphyl1 gene. www.plantcell.org /cgi/content/full/14/9/2085   (4197 words)

Phyllotaxis Screensaver   (Site not responding. Last check: 2007-10-27) The Phyllotaxis Screensaver project is a nice little project I did for myself. The Fibonacci Numbers and the Golden Ratio appear in many ways in nature: from the multiplying behavior of rabbits to the growth of seashells. I also used phyllotaxis for the amicitia public web interface and the CreditGenerator program. www.evolutie.org /phyllotaxis.html   (162 words)

A Collision-based Model of Spiral Phyllotaxis   (Site not responding. Last check: 2007-10-27) Well known examples include the layout of seeds in a sunflower head and the arrangement of scales on a pineapple. This paper presents a method for modeling spiral phyllotaxis based on detecting and eliminating collisions between the organs while optimizing their packing. In contrast to geometric models previously used for computer graphics purposes, the new method arranges organs of varying sizes on arbitrary surfaces of revolution. algorithmicbotany.org /papers/phyllo.sig92.html   (154 words)

CiteULike: livingthingdan's phyllotaxis   (Site not responding. Last check: 2007-10-27) Recent papers added to livingthingdan's library classified by the tag phyllotaxis. posted to grammar phyllotaxis plant simulation teachmyself by livingthingdan as posted to complexity compsci epsilonmachine informationtheory intro memory phyllotaxis by livingthingdan as www.citeulike.org /user/livingthingdan/tag/phyllotaxis   (102 words)

Find in a Library: On the interpretation of phenomena of phyllotaxis. Find in a Library: On the interpretation of phenomena of phyllotaxis. To find a library, type in a postal code, state, province, or country. WorldCat is provided by OCLC Online Computer Library Center, Inc. on behalf of its member libraries. www.worldcatlibraries.org /wcpa/ow/43315a2453996175.html   (40 words)

Processing 1.0 _ALPHA_ - phyllotaxis spiral lattice Please visit the The Processing (BETA) board for current information. I was trying to implement the function from this page on phyllotaxis: http://www.math.smith.edu/~phyllo/About/Lattices/SpiralLattices.html The code below doesn't result in anything that looks like a pattern. I've tried converting to radians too, with no luck. www.processing.org /discourse/yabb/YaBB.cgi?board=Programs;action=display;num=1103483355   (222 words)

Table of contents for Library of Congress control number 93015285   (Site not responding. Last check: 2007-10-27) Table of contents for Phyllotaxis : a systemic study of plant pattern morphogenesis / Roger V. Jean. Hyperbolic transformations of the cylindrical lattice Handbook of authors Indexes. Library of Congress subject headings for this publication: Phyllotaxis Mathematical models, Plant morphogenesis Mathematical models www.loc.gov /catdir/toc/cam028/93015285.html   (100 words)

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