[click on image to see a larger one]
Human vision:
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Reflected UV:
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Simulated butterfly vision:
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Simulated bee vision (new version):
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Quadriptych (details) of human vision, UV, new simulated bee and butterfly vision (left to right, top to bottom):
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Bidens has a strong visible UV pattern, its petal tips are UV bright around 365nm, its center is quite UV dark, so this gets quite nicely visible, also in simulated butterfly and the new bee vision.
I have written about Bidens previously HERE
Stay tuned, more will follow on that fascinating subject...
More info on this very interesting field may be found on my site http://www.pbase.com/kds315/uv_photos