Consider how the wild flowers grow.
They do not labor or spin.
Yet I tell you, not even Solomon in all his splendor was dressed like one of these.
Luke 12:27 NIV
"A lowly dandelion is stuck in the ground. It can’t move. It seems hopelessly chained to earth by its roots. But one day, it will give its young marvelous wings that will let it soar above the landscape, to enjoy a brief but wondrous journey, traveling possibly for miles till it gently descends to a paradise its ancestors could never imagine: a land of fertile soils and fountains. Your lawn.
Nature says:
The paper in Nature is titled, “A separated vortex ring underlies the flight of the dandelion.” The authors seem jazzed by what they found:
The editors emphasize that the dandelion’s flight trick depends on finely-tuned parts:
They do not labor or spin.
Yet I tell you, not even Solomon in all his splendor was dressed like one of these.
Luke 12:27 NIV
"A lowly dandelion is stuck in the ground. It can’t move. It seems hopelessly chained to earth by its roots. But one day, it will give its young marvelous wings that will let it soar above the landscape, to enjoy a brief but wondrous journey, traveling possibly for miles till it gently descends to a paradise its ancestors could never imagine: a land of fertile soils and fountains. Your lawn.
Nature says:
Every child knows that blowing on a dandelion clock will send its seeds floating off into the air. But physicists wanted to know more. How does an individual seed manage to maintain such stable flight? Researchers at the University of Edinburgh studied the fluid dynamics of air flow around the seed and discovered a completely new type of flight. It’s based on a previously unknown kind of vortex which may even be common in the plant and animal kingdoms, now that we know where to look.Jeremy Kahn, also writing in Nature, calls it an “‘impossible’ method never before seen in nature.” A beautiful film clip describes how air flowing up through the bristles of the “pappus” as it is called creates a “separated vortex ring” above it that literally sucks the seed up into the air.
The paper in Nature is titled, “A separated vortex ring underlies the flight of the dandelion.” The authors seem jazzed by what they found:
The porosity of the dandelion pappus appears to be tuned
precisely to stabilize the vortex, while maximizing aerodynamic loading and minimizing material requirements. The discovery of the separated vortex ring provides evidence of the existence of a new class of fluid behaviour around fluid-immersed bodies that may underlie locomotion, weight reduction and particle retention in biological and manmade structures.
The editors emphasize that the dandelion’s flight trick depends on finely-tuned parts:
All falling objects, from feathers to cannon balls, create turbulence in their wake. But it takes a rare combination of size, mass, shape and, crucially, porosity for the pappus to generate this vortex ring. Size is also particularly important, because from the point of view of something as small as a pappus, the air is appreciably viscous. At such a scale, a parachute consisting of a bunch of bristles is as effective as the aerofoil found in larger seeds that disperse from taller plants — such as the winged seeds of the maple. In the same way, the tiniest insects do not fly with solid wings, but swim through the air using ‘paddles’ made of bristles.Perhaps most surprisingly, the trick depends on the blank spaces between the parts. What goes on there depends on the solid materials and how they are arranged." EN&V
