Loading...

How the Cucumber Tendril Coils and Overwinds

11,005 views

Loading...

Loading...

Loading...

Rating is available when the video has been rented.
This feature is not available right now. Please try again later.
Published on Sep 1, 2012

How the Cucumber Tendril Coils and Overwinds
Time-lapse movies of tendril searching for a support and coiling (Movie S1)

- How Cucumber Tendrils Curl
http://news.sciencemag.org/sciencenow...

- Uncoiling the cucumber's enigma
In the creeping plant's tendrils, researchers discover a biological mechanism for coiling and stumble upon an unusual type of spring
http://www.seas.harvard.edu/news-even...

Reference
How the Cucumber Tendril Coils and Overwinds
Science 31 August 2012: Vol. 337 no. 6098 pp. 1087-1091 DOI: 10.1126/science.1223304
http://www.sciencemag.org/content/337...

Abstract
The helical coiling of plant tendrils has fascinated scientists for centuries, yet the underlying mechanism remains elusive. Moreover, despite Darwin's widely accepted interpretation of coiled tendrils as soft springs, their mechanical behavior remains unknown. Our experiments on cucumber tendrils demonstrate that tendril coiling occurs via asymmetric contraction of an internal fiber ribbon of specialized cells. Under tension, both extracted fiber ribbons and old tendrils exhibit twistless overwinding rather than unwinding, with an initially soft response followed by strong strain-stiffening at large extensions. We explain this behavior using physical models of prestrained rubber strips, geometric arguments, and mathematical models of elastic filaments. Collectively, our study illuminates the origin of tendril coiling, quantifies Darwin's original proposal, and suggests designs for biomimetic twistless springs with tunable mechanical responses.

Supplementary Materials Video
Download Supplement PDF
http://www.sciencemag.org/content/sup...

Video
Movie S1
http://www.sciencemag.org/content/sup...
Time-lapse movies of tendril searching for a support and coiling

Movie S2
http://www.sciencemag.org/content/sup...
Drying and rehydrating a fiber ribbon

Movie S3
http://www.sciencemag.org/content/sup...
Drying and rehydrating a whole tendril

Movie S4
http://www.sciencemag.org/content/sup...
Unwinding of a physical model

Movie S5
http://www.sciencemag.org/content/sup...
Overwinding of a fiber ribbon

Movie S6
http://www.sciencemag.org/content/sup...
Overwinding in a physical model with ribbon on inside and wire on outside

Movie S7
http://www.sciencemag.org/content/sup...
Unwinding of a numerical filament

Movie S8
http://www.sciencemag.org/content/sup...
Overwinding of a numerical filament

Movie S9
http://www.sciencemag.org/content/sup...
Unwinding of a young cucumber tendril

Movie S10
http://www.sciencemag.org/content/sup...
Overwinding of an old cucumber tendril

Movie S11
http://www.sciencemag.org/content/sup...
Overwinding of a passiflora tendril

Loading...

When autoplay is enabled, a suggested video will automatically play next.

Up next


to add this to Watch Later

Add to

Loading playlists...