Sunday, July 31, 2016

How to stand out in the crowd - Gazania rigens shows its ecologic advantage vs Rudbeckia fulgida and Rudbeckia hirta using intense UV reflection III

Today about how even some UV reflecting flowers (Gazania rigens) have achieved a competitive edge over other UV reflecting flowers (Rudbeckia fulgida and R. hirta) by making use of a specific very intense UV reflection around 370nm. This will be shown in human vision, in reflected ultraviolet photography and also in simulated bee vision. I was using my "work horse" UV filter, the Baader-U filter for reflected UV, my XBV filter for simulated bee vision aside from a visible light shot. Lens was my UV-Nikkor 105mm quartz flourite lens. Light source was a modified Xenon flash. All shots were done at f11. [These shots were done with a new camera system and are available on request in very high resolution (40 and 60 Mp)].

[click on image to see a larger one]

Rudbeckia fulgida + R. hirta vs white Gazania rigens, visible image:  

Rudbeckia fulgida + R. hirta vs white Gazania rigens, reflected UV image:  

Rudbeckia fulgida + R. hirta vs white Gazania rigens, simulated bee vision image:  

In visible light, all these flowers are rather bright yellow / orange (Rudbeckia) and white (Gazania) to our human eye. But the white Gazania rigens against the Rudbeckia fulgida and R. hirta flowers shows an even more prominent and bright bullseye pattern in reflected UV (only visible to bees and butterflies), as its petals are very, very UV bright (around 370nm) and its center is very UV dark, compared to the other UV reflecting flowers, which makes them clearly even more visible in UV, hence creating an impressive competitive edge in terms of chances for getting pollinated even against those other flowers with UV bullseye pattern - and all this gets nicely visible, also in simulated bee vision.

I have written HERE about it before.

Stay tuned, more will follow on that fascinating subject...