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Math in Nature.Key Mathematics in Nature: Bees, Honeycombs Bubbles, and Mud Cracks Jonna Massaroni, Catherine Kirk Robins, Amanda MacIntosh & Amina Eladdadi, Department of Mathematics Bees & Honeycombs Bubbles Mud Cracks The most fascinating application of hexagons is the Look virtually anywhere, and you can find bubbles. As the Earth’s surface loses water not only are mud honeycomb. It is common knowledge that circular cells Whether they’re from the soap in your kitchen sink or cracks formed, but polygons as well. These polygons create wasted space, whereas hexagonal cells, such as from the hot gasses vented from the ocean floor, all create a form of repeating symmetry throughout the the ones that can be found in honeycombs, are more bubbles are subjected to the same mathematical rules dried mud puddles. As the mud loses water, this causes efficient. In fact, if one places six regular hexagons in a and concepts. Bubbles are considered to be what are it to shrink and separate. The drying mud becomes ring with each pair sharing one common side, a free called, “minimal surface structures.” Essentially, bubbles brittle and not only forms into its shapes of polygons but seventh hexagon appears in the center. This seven- form a spherical shape that employs the least amount of is separated by vertical cracks. These polygons are hexagon honeycomb arrangement maximizes the area surface area needed to enclose any given volume of air made up of straight lines creating a path or circuit. This enclosed in the honeycomb while minimizing the or gas. They remain spherical because there is an equal symmetry formed by mud puddles is also formed perimeter. Which ultimately means the minimization of amount of pressure against all points on the bubble, similarly by basalt and lava. Once they are dried or the wax needed for the construction of the arrangement. therefore, no distinct edges can be maintained. The only cooled down, polygons are formed leaving a symmetric It is evident that bees do not have to take this course in exception to this rule is when multiple bubbles join pattern on the Earth’s surface. This natural wonder is all ABSTRACT optimization theory to make their honeycomb. This is together. Foam, for instance, is composed of many around us. Without looking very far, symmetry can be because this same hexagonal pattern can be seen in a bubbles of various shapes and sizes. When they are found in just about anything. collection of identical coins placed together, in contact, joined together they change shapes to maximize their Polygons are fascinating, especially on a flat surface. Although, by looking at this pattern of space-filling capabilities. Though their appearances can when they are approximated in coins it becomes clear that if the bees wish to tessellate all be different, when three or more bubbles join together nature. When looking carefully on can (covering a plane by using the repetition of a single they merge so that the three angles of their connection see them all around us. For example, shape with out gaps or overlap) a plane for their form a 120 degree angle (the same number found in the hexagonal convection-cell clouds, honeycomb a circle or cylindrical shape will not work. hexagonal formation of bee hives). The bubbles alter mud cracks, or even sea salt flats Some people believe, such as Pappus of Alexandria, their formations to minimize the energy required to exhibit the same pattern. that bees are gifted with “a certain geometrical contain the multiple volumes of gases, however, if all forethought” and “There being, then, three figures which surrounding bubbles popped and only one remained, it Here, we explore how polygons of themselves can fill up the space around a point, viz. would revert to its spherical shape. configuration is achieved throughout The triangle, the square and the hexagon, and the bees nature. We present three examples have wisely selected for their structure that which Theorem: The that exhibit patterns which can be contains more angles, suspecting that it could hold more (a) Two bubbles patterns of cracks described mathematically: honey than either of the two.” At the same time, there meeting at point M. All observed in mud that honeycombs, bubbles and mud are other, later, writers that believe that this hypothesis three bubbles meet at cracks. The hexagonal honeycombs was incorrect, and that the hexagonal cell created by the has been dried by the 120 angles-the three sun form curves that maximize the enclosed region and bees was “no more than the necessary result of equal shaded angles are all minimize the wax needed for pressures, each bee striving to make its own little circle 120 degrees. (b) The often intersect in right construction, while satisfying the bees' as large as possible." The honeycomb produced by bees geometry associated angles. cell-size constraint. Bubbles are a is among works of art produced by animals. Their with two bubbles. The real-world example of what honeycomb is geometrically perfect and leads scientists pink angles are 30 source : Wolfram Mathworld to question whether it is the result of self-organizing degrees, and the mathematicians call a minimal principles of packing or genetic predisposition. green angles are 60 surface. A minimal surface is one that degrees.The numbers has the smallest area possible, while refer to the steps in the meeting certain conditions. The drying derivation in the text. mud becomes brittle and not only forms into its shapes of polygons but Honeycomb Conjecture is separated by vertical cracks. Theorem: Any partition of the plane into regions of equal area has perimeter at least that of the regular hexagonal grid (i.e., the honeycomb, illustrated above). Pappus refers to the problem in his fifth book. The conjecture was REFERENCES finally proven by Hales (1999, 2001). 1. Adam, John A. Mathematics in Nature Modeling, Patterns in the Natural World: Princeton University Press: 2003. 2. Sascha Hilgenfeldt, Bubble Geometry, the Nieuw Archief voor Wiskunde, 2002; 5(3): 224-230 The regular tessellation Consisting of regular hexagons Poster Design & Printing by Genigraphics® - 800.790.4001 .
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