White Gazania Flower in VIS and reflected UV

[Dr Klaus Schmitt]

Here about a white Gazania flower, most likely Gazania rigens. Shot in visible and ultraviolet light, using the Baader-U filter and a high power Xenon flash, as well as an UV sensitive camera.

Visible light image:

Ultraviolet (UV) light image:

Diptych VIS - UV:

The petals of this white Gazania flower are quite special, since they show in UV an otherwise invisible bright rim (reflecting around 370nm) against a UV darker, but still reflective (around 385nm) inside. The stigmas are also very UV bright, whereas the stamen are quite dark so overall create quite distinct UV nectar guides for their pollinators.

 

[Asher Kelman]

Diptych VIS - UV:

Klaus,

Interesting that stamens are dark! I wonder why?

asher

 

[Tom Robbins]

The diptych is an absolute stunner. The bright rims of the petals in UV are a great illustration of the limitation of the wavelengths visible to humans.

 

[Dr Klaus Schmitt]

Thanks guys, appreciate it!

Asher, most flowers have dark stamens, but I haven't found out a reason yet, even teh biologists I asked couldn't tell.

 

[Bart_van_der_Wolf]

Thanks guys, appreciate it!

Asher, most flowers have dark stamens, but I haven't found out a reason yet, even teh biologists I asked couldn't tell.

Hi Klaus,

Maybe dark means good, in insect speak...

Cheers,
Bart

 

[Asher Kelman]

Thanks guys, appreciate it!

Asher, most flowers have dark stamens, but I haven't found out a reason yet, even the biologists I asked couldn't tell.

Klaus,

Perhaps there's a survival advantage for the flower. By making the stamens dark, there's more chance that the foraging insects might accidentally brush against them, dusting pollen on to their surfaces. Also birds, (seeing UV), would have a harder time feeding on seeds that were not ready for eating and spreading that way.

Asher

 

[Lakshitha Udara]

Nice comparison