Oxalis Triangularis Photonasty Timelapse

Description:

: This file was selected as the media of the day for 31 July 2010. It was captioned as follows: English: Oxalis triangularis (Purple Shamrock) is a classic example of a plant which responds with movement to external stimulus. The leaves open and close in response to varying light levels with the result that they are open during during the day and close at night. This is true movement (i.e. not growth) and is non-directional with respect to the stimulus making it an example of nastic movement towards light: photonasty. One image captured every 30 seconds for about 1.5 hours, played back at 25 frames per second; ~750x actual speed. The exposure time was progressively increased through the video so the drop in ambient light levels are not seen. Other languages English: Oxalis triangularis (Purple Shamrock) is a classic example of a plant which responds with movement to external stimulus. The leaves open and close in response to varying light levels with the result that they are open during during the day and close at night. This is true movement (i.e. not growth) and is non-directional with respect to the stimulus making it an example of nastic movement towards light: photonasty. One image captured every 30 seconds for about 1.5 hours, played back at 25 frames per second; ~750x actual speed. The exposure time was progressively increased through the video so the drop in ambient light levels are not seen.Македонски: Виолетова детелина (Oxalis triangularis) врши настија - ненасочено движење на растението како реакција на светлинските или атмосферските промени. Во овој случај детелината се отвора на дневна светлина, а се затвора ноќе. Summary[edit] Description: English: Oxalis triangularis (Purple Shamrock) is a classic example of a plant which responds with movement to external stimulus. The leaves open and close in response to varying light levels with the result that they are open during during the day and close at night. This is true movement (i.e. not growth) and is non-directional with respect to the stimulus making it an example of nastic movement towards light: photonasty. One image captured every 30 seconds for about 1.5 hours, played back at 25 frames per second; ~750x actual speed. The exposure time was progressively increased through the video so the drop in ambient light levels are not seen. Македонски: Виолетова детелина (Oxalis triangularis) врши настија - ненасочено движење на растението како реакција на светлинските или атмосферските промени. Во овој случај детелината се отвора на дневна светлина, а се затвора ноќе. Date: Taken on 12 June 2010. Source: Own work. Author: Richard Wheeler.