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Alsomitra macrocarpa seed (syn. Zanonia macrocarpa)
 

 

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http://commons.wikimedia.org/wiki/File:Alsomitra_macrocarpa_seed_(syn._Zanonia_macrocarpa).jpg

Summaryedit

Description

Kebun Raya, Bogor, Indonesia.

A bit of flowery prose from an essay that I wrote in 2001 on wind-dispersed seeds & fruits:

"Every now and then, field botanists are treated to transcendental moments when the light is golden, the air is fresh, interesting plants are at hand, and the hardships of field work just melt away. During those times, scientific insights arrive with astonishing clarity and grace. One such moment for me came on a sunny afternoon in the Kebun Raya Botanic Garden, in Bogor, Indonesia, some years ago. On that memorable day, I was transfixed as I watched dozens of winged seeds of Alsomitra macrocarpa (Cucurbitaceae, the squash family) glide to the ground in broad, lazy spirals. The seeds spilled out from a fruit hanging on the liana climbing on one of the enormous old trees in the garden. All the principles of aerodynamics as they relate to seed dispersal were manifest in that one lovely moment.

"The gliding seeds of Alsomitra exhibit two kinds of motion: The forward gliding motion, which takes the seed on a helical, downward path, and phugoid oscillations, in which the gliding seed gains lift, stalls, drops briefly until it accelerates enough to generate lift, starting the process over again. Phugoid oscillations are well known to aviation engineers and model airplane fliers, because they can destabilize mechanized flight, but in the seeds of Alsomitra, phugoid oscillations add a graceful rhythm to the descent, and more importantly, slow the descent of the seeds giving them more time aloft. Time aloft is the sine qua non of successful dispersal by wind."

Date
Source Alsomitra macrocarpa seed (syn. Zanonia macrocarpa)
Author Scott Zona from Miami, Florida, USA

Licensingedit

w:en:Creative Commons
attribution
This file is licensed under the Creative Commons Attribution 2.0 Generic license.
You are free:
  • to share – to copy, distribute and transmit the work
  • to remix – to adapt the work
Under the following conditions:
  • attribution – You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work).

Checked copyright icon.svg This image was originally posted to Flickr by scott.zona at https://www.flickr.com/photos/12017190@N06/5616740256. It was reviewed on by FlickreviewR and was confirmed to be licensed under the terms of the cc-by-2.0.

Licensingedit

w:en:Creative Commons

attribution share alike

This file is licensed under the Creative Commons Attribution-Share Alike 2.0 Generic license.
You are free:
  • to share – to copy, distribute and transmit the work
  • to remix – to adapt the work
Under the following conditions:
  • attribution – You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work).
  • share alike – If you alter, transform, or build upon this work, you may distribute the resulting work only under the same or similar license to this one.

Checked copyright icon.svg This image was originally posted to Flickr by scott.zona at https://www.flickr.com/photos/12017190@N06/5616740256. It was reviewed on by FlickreviewR and was confirmed to be licensed under the terms of the cc-by-2.0.

Photo's description:
Kebun Raya, Bogor, Indonesia. A bit of flowery prose from an essay that I wrote in 2001 on wind-dispersed seeds & fruits: "Every now and then, field botanists are treated to transcendental moments when the light is golden, the air is fresh, interesting plants are at hand, and the hardships of field work just melt away. During those times, scientific insights arrive with astonishing clarity and grace. One such moment for me came on a sunny afternoon in the Kebun Raya Botanic Garden, in Bogor, Indonesia, some years ago. On that memorable day, I was transfixed as I watched dozens of winged seeds of Alsomitra macrocarpa (Cucurbitaceae, the squash family) glide to the ground in broad, lazy spirals. The seeds spilled out from a fruit hanging on the liana climbing on one of the enormous old trees in the garden. All the principles of aerodynamics as they relate to seed dispersal were manifest in that one lovely moment. "The gliding seeds of Alsomitra exhibit two kinds of motion: The forward gliding motion, which takes the seed on a helical, downward path, and phugoid oscillations, in which the gliding seed gains lift, stalls, drops briefly until it accelerates enough to generate lift, starting the process over again. Phugoid oscillations are well known to aviation engineers and model airplane fliers, because they can destabilize mechanized flight, but in the seeds of Alsomitra, phugoid oscillations add a graceful rhythm to the descent, and more importantly, slow the descent of the seeds giving them more time aloft. Time aloft is the sine qua non of successful dispersal by wind."


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EXIF data:
File name alsomitra_macrocarpa_seed__syn._zanonia_macrocarpa_.jpg
Size, Mbytes 8.8625361328125
Mime type image/jpeg
Camera manufacturer Nikon
Camera model Nikon SUPER COOLSCAN 5000 ED
Orientation of image 1
Image resolution in width direction 350
Image resolution in height direction 350
Unit of X and Y resolution 2
Exposure time 0/1000000 sec (0)
F number f / 0
Compressed bits per pixel 0
Exif version 0220
Lens focal length 0 mm
Shutter speed 0
Aperture 0
Brightness 0
Exposure bias 0
Maximum lens aperture 0
Supported Flashpix version 0100
Color space information 65535
Exif image width 3940
Exif image length 2620
Focal plane X resolution 0
Focal plane Y resolution 0
Exposure index 0
Software used Adobe Photoshop CS4 Macintosh




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