Which geometric shape is most economical
These are called periodic minimal surfaces. Periodic just means a structure that repeats identically again and again, or in other words, a regular pattern. When such patterns were discovered in the 19th century, they seemed to be just a mathematical curiosity. But now we know that nature makes use of them. The cells of many different types of organisms, from plants to lampreys to rats, contain membranes with microscopic structures like this.
Perhaps they isolate one biochemical process from another, avoiding crosstalk and interference. Some butterflies, such as the European green hairstreak and the emerald-patched cattleheart, have wing scales containing an orderly labyrinth of the tough material called chitin, shaped like a particular periodic minimal surface called the gyroid.
Interference between light waves bouncing regular arrays of ridges and other structures on the wing-scale surface causes some wavelengths—that is, some colors—to disappear while others reinforce each other. So here the patterns offer a means of producing animal color.
T he skeleton of the sea urchin Cidaris rugosa is a porous mesh with the shape of another kind of periodic minimal surface. The open lattice structure means that the material is strong without being too heavy, rather like the metal foams used for building aircraft. To make orderly networks from hard, stiff mineral, these organisms apparently make a mold from soft, flexible membranes and then crystallize the hard material inside one of the interpenetrating networks.
Other creatures may cast orderly mineral foams this way for more sophisticated purposes. Because of the way that light bounces off the elements of the patterned structure, such trellises can act rather like mirrors to confine and guide light. A honeycomb arrangement of hollow microscopic channels within the chitin spines of a peculiar marine worm known as the sea mouse turns these hair-like structures into natural optical fibers that can channel light, making the creature change from red to bluish green depending on the direction of the illumination.
This color change might serve to deter predators. This principle of using soft tissues and membranes as molds for forming patterned mineral exoskeletons is widely used in the sea. Some sponges have exoskeletons made of bars of mineral linked like climbing frames, which look remarkably similar to the patterns formed by the edges and junctions of soap films in foam—no coincidence, if surface tension dictates the architecture.
Such processes, known as biomineralization, generate spectacular results in marine organisms called radiolarians and diatoms. Some of these have delicately patterned exoskeletons made from a mesh of mineral hexagons and pentagons: You might call them the honeycombs of the sea.
When the German biologist and talented artist Ernst Haeckel first saw their shapes in a microscope in the late 19th century, he made them the star attraction of a portfolio of drawings called Art Forms in Nature , which were very influential among artists of the early 20th century and still inspire admiration today. To Haeckel, they seemed to offer evidence of a fundamental creativity and artistry in the natural world—a preference for order and pattern built into the very laws of nature.
All rights reserved. Nautilus uses cookies to manage your digital subscription and show you your reading progress.
The ratio is always less than 1 so hexagonal is always more efficient. The more compact your structure, the less wax you need to construct the honeycomb. Wax is expensive. Hexagon Definition: In mathematics and geometry, a Hexagon is defined as a polygon a closed two-dimensional shape with straight sides with 6 sides.
Note that Hexagons have 6 sides and 6 angles. A six-sided shape is a hexagon, a seven-sided shape a heptagon, while an octagon has eight sides…. In geometry, the hexagonal prism is a prism with hexagonal base. This polyhedron has 8 faces, 18 edges, and 12 vertices. Since it has 8 faces, it is an octahedron. However, the term octahedron is primarily used to refer to the regular octahedron, which has eight triangular faces.
I put together 2 trapezoids to make a hexagon. It has 6 sides and 6 vertices. It has 2 equal parts. My new shape has 2 trapezoids and 4 triangles. Begin typing your search term above and press enter to search. Press ESC to cancel. Skip to content Home Architecture What is the strongest geometric shape and why? Ben Davis August 22, What is the strongest geometric shape and why? What is the most powerful shape? The shape starts with the development of a cell.
During an embryo's formation, tissues will bend into a number of shapes to become an organ down the road. For example, epithelial cells contribute to the outer layer of human skin the epidermis and help with selective absorption, protecting the body, transporting cells, and sensing their surroundings. These cells pack in tightly with each other in order to accomodate the curve that happens while they develop. Researchers have long assumed that these cells pack together in either columns or bottle-like shapes.
An international team of scientists redefined that assumption, serendipitously discovering a new geometric shape. They discovered that the tissues bend in a previously undescribed shape to minimize the energy used by the body and to maximize the stability of the cells as they form.
The new shape and the process of discovering that shape are both detailed in the journal Nature Communications. The team used a computational modeling system that used Voronoi diagramming. Voronoi diagramming is a tool that's used in understanding geometrical organization. To our surprise the additional shape didn't even have a name in math!
0コメント