You don’t want a dandelion to know which means the wind blows. However it may assist.
On any given dandelion, some seeds are destined to go north, whereas others are fated to fly east, south or west, and each course in between. In impact, every dandelion seed is programmed to launch for a wind coming from one course and resists winds from different instructions, in keeping with analysis to be introduced on the American Bodily Society’s Division of Fluid Dynamics in Indianapolis on November 20.
Dandelion seeds are prone to totally different wind instructions relying on the place they’re on the seed head, says Jena Shields, a biophysicist at Cornell College. The feathery seeds on the facet going through a breeze will let go most simply; the others maintain on tens to a whole bunch of instances tighter — till the wind shifts.
It’s a phenomenon that Shields got down to examine after her adviser seen the best way dandelions responded as his toddler performed with the flowers.
Shields measured the power it takes to pluck dandelion seeds by supergluing a nice wire to the tufted ends and pulling them from the seed heads at varied angles. This seed-by-seed examine mimicked what occurs when wind, or a baby’s breath, pushes them over. As a result of every seed is most prone to winds from distinct instructions, it helps forestall seeds from all going the identical means, Shields says, and should clarify why the vegetation are so profitable at spreading. As soon as blown off a dandelion, the umbrella-like tuft on a seed carries it on the breeze that pulled it away (SN: 10/17/18).
“However a powerful, turbulent wind can nonetheless ship all of the seeds flying in the identical course,” Shields says, so the impact can’t assure {that a} highly effective gust or exuberant little one received’t blow off all of the seeds without delay.
