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Tropic-bird landing

Tropic-bird landing
Photo Information
Copyright: Tom Conzemius (pirate) Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 799 W: 152 N: 1186] (7474)
Genre: Animals
Medium: Color
Date Taken: 2013-01-15
Categories: Birds
Camera: Canon 7D, 100-400L is
Exposure: f/6.3
More Photo Info: [view]
Photo Version: Original Version
Date Submitted: 2013-01-26 9:53
Viewed: 2388
Points: 8
[Note Guidelines] Photographer's Note
White tailed Tropicbird
In landing birds one can easily see the alula

from Wikipedia
The alula is a small projection on the anterior edge of the wing of modern (and some ancient) birds. The word is Latin and means "winglet"; it is the diminutive of ala, meaning "wing". The alula is the freely moving first digit, a bird's "thumb," and is typically covered with three to five small feathers, with the exact number depending on the species. Like the larger flight feathers found on the wing's trailing edge, these alula feathers are asymmetrical, with the shaft running closer to anterior edge.

In most situations, the alula is held flush against the wing; however, it can be manipulated. When flying at slow speeds or landing, the bird moves its alula slightly upwards and forward, which creates a small slot on the wing's leading edge. This functions in the same way as the slats on the wing of an aircraft, allowing the wing to achieve a higher than normal angle of attack and thus lift without resulting in a stall. During stretching of the wing down toward the ground, the alula is abducted from the wing and can be clearly viewed.
Alula in ancient birds

The presence of an alula has been confirmed in several now-extinct ancient relatives of modern birds, including Eoalulavis hoyasi (an enantiornithine from the mid-Cretaceous, 115 mya) and the earlier Protopteryx fengningensis.[3] Since these species are not closely related to modern birds, either the alula evolved twice, or it did so more than 130 million years ago.

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Critiques [Translate]

Hello Tom
An elegant photo of a likewise bird!
Nicely chosen moment, perfectly still, good focus, excellent detail and exposure.
A fine photo.
regards yiannis

Hello Tom,
very nice capture of this inflight bird with good detail and colour.
great tonal range and the back ground.
best wihes,

OMG. What a stunning capture of a flying bird. Never seen anything like this before. Natural colors and fine details...... Nitin

Hello Tom

Its landing flight pose with the long tail
with the POV and framing, it gives
dynamism to the image, TFS


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