What kind of flowers are these? (eerie)

  • Thread starter berkeman
  • Start date
  • #1
berkeman
Mentor
64,193
15,441
I run by these flowers near my work on some of my noon workouts, and the first time I ran past them I had to stop because I thought I was having some kind of vision problem. When I looked right at the flowers they looked like one color, but when I saw them out of my peripheral vision, they looked like they were a different color (red versus purple, respectively).

I thought I'd figured out the cause as being my eyeglasses (which have UV filtering) -- they tend to make the flowers look less purple and more red, which would match the UV filter characteristic extending down a bit into the visible violet range. I figured that I saw more purple in the flowers with my peripheral vision because that light wasn't going through the eyeglass lenses.

But then today when I saw the flowers from farther away in bright sunlight, the middle part of the bank of flowers looked more red, and there was a thin blue halo around the whole group, especially along the top edge. Strange (and very beautiful).

Does anybody know what kind of flowers these are? I wanted to do some reading to see if this unusual visual effect has been noticed and documented.

Thanks! :smile:

Flowers by PHD Better.jpg
 

Attachments

  • Flowers by PHD Better.jpg
    Flowers by PHD Better.jpg
    112.3 KB · Views: 772

Answers and Replies

  • #2
OmCheeto
Gold Member
2,265
2,741
My best guess is Calandrinia grandiflora, Chilean Rock Purslane.
Here's http://www.marathonlandscape.com/wp-content/uploads/2010/01/IMG_1782.jpg from http://www.marathonlandscape.com/?page_id=63; "We serve the entire Monterey Bay Area including Los Gatos and Saratoga."
I think that's Silicon Valley-ish area.

My worst guesses are corn poppy and rose campion.
 
  • Like
Likes collinsmark and berkeman
  • #3
berkeman
Mentor
64,193
15,441
Thanks Om. Yes, I should have said this is in Santa Clara California. Silicon Valley. :smile:
 
  • #4
BillTre
Science Advisor
Gold Member
2022 Award
2,219
7,367
Google images search says they are Bougainvillea.
However, both the petals and the plant structure look different to me. Perhaps a closer picture of the flowers/plant would work better.
Or someone more knowledgeable about flowers (such as @jim mcnamara ).

Here are some thoughts on your color observations (not sure any are all that pertinent to what you're describing however):

1) the periphery of the retina is mostly composed of rod receptors (lower light level, often called black and white, broad wavelength sensitivity). The brain provides peripheral colors by filling in based on what's previously been seen (in the recent experiential past). See graph of cone vs. rod distribution in this link. The fovea contains most of the color detecting cones and rapidly scans aspects of a scene to build up and overall idea of what's out there. I am avoiding using image since it is not an instantaneous view, but built up over time.

2) The retinal and brain both have mechanisms where contrasts are enhanced (and used to build up large scale observed objects (like lines)) from circle surround sensory fields. There are also color contrast systems R vs. G and Blue vs. Yellow). Not sure how this might work here, ut are optical illusions based on this.

3) If there some of the flower's color is due to structural elements rather than color pigments, the colors can change depending on the the angles of observation and illumination.

4) The color of the light illuminating an object can affect the perceived color.
 
Last edited by a moderator:
  • #5
jim mcnamara
Mentor
4,691
3,633
Looks like the genus Calandrina - Chilean rock purslane @OmCheeto got it I think. Calandrina spectablilis most likely. An import.

There is a structural element with these flowers' pigmentation in cells. They refract light as well as reflect it. The wider the angle of incidence to viewing angle, the more color change you see. Really wide angles and the color fades.

@BillTre his #3 is probably the best explanation.

Hint: pictures of flowers taken at about 1 foot make this whole process less guessworthy
 
  • Like
Likes BillTre and berkeman
  • #6
Borek
Mentor
29,172
3,848
Google images search says they are Bougainvillea.

Unlikely IMHO, bougainvillea is either a bush or wine and wouldn't make sense planted in a flower garden directly on the flat ground.
 
  • #7
Suyash Singh
168
1
These are in my mom's garden in winters but my gardener won't know their names cause he is illiterate.They refer plants as the light purple one ,the purple with dots ,etc in layman language. I don't have uv glasses.
 
  • #8
OmCheeto
Gold Member
2,265
2,741
...
There is a structural element with these flowers' pigmentation in cells. They refract light as well as reflect it. The wider the angle of incidence to viewing angle, the more color change you see. Really wide angles and the color fades.
...
Fascinating.
Looking at Berkeman's original image, I sensed a subtle hue difference in the central portion vs the periphery.
I went ahead and sampled it, and found a very subtle shift from red to blue, when going from the center to the periphery: rgb(220, 58, 209) --> rgb(207, 60, 220)

But then I found out that honeybees can't see red!; "... honey bees also have a weak point in their vision as they cannot see the color red. " [ref]
Not sure about Andean bees, which is where this particular flower is from.

But I went ahead and removed the red portion from the two colors, and compared that to what humans would see:

human.vs.bee.flower.vision.maybe.png

Looks like a color blindness test!

Anyways, after some more googling, I also discovered a new discovery:

Petals produce a 'blue halo' that helps bees find flowers
Date: October 18, 2017
Source: University of Cambridge
Summary: Latest research has found that several common flower species have nanoscale ridges on the surface of their petals that meddle with light when viewed from certain angles.​

That's just 6 months ago!

I have to admit, I've never noticed this "Blue halo" before.
Though, I have noticed that Rose Campions catch my eye, in a weird "That plant is doing something to light that I can't describe." kind of way. (First noticed this around 1990.)
No other flower I've ever seen does it like it does.
 

Attachments

  • human.vs.bee.flower.vision.maybe.png
    human.vs.bee.flower.vision.maybe.png
    3.8 KB · Views: 613
  • Like
Likes pinball1970, BillTre and berkeman
  • #9
berkeman
Mentor
64,193
15,441
Anyways, after some more googling, I also discovered a new discovery:

Petals produce a 'blue halo' that helps bees find flowers
Date: October 18, 2017
Source: University of Cambridge
Summary: Latest research has found that several common flower species have nanoscale ridges on the surface of their petals that meddle with light when viewed from certain angles.
That's just 6 months ago!
Thanks Om! Awesome stuff. So you're saying I'm not crazy after all? o0)
 
  • #10
BillTre
Science Advisor
Gold Member
2022 Award
2,219
7,367
In addition to lacking the ability to see red (something I was not aware of) bees can see near UV (bee purple).
Sometimes people make photos with the colors shifted so people can see what bees see (the patterns not the actual psychological internal colors). The patterns often make the flowers look like a target.

So you're saying I'm not crazy after all? o0)
I considered that (along with colorblindness), but left it off my list. :smile:
 
  • #11
jim mcnamara
Mentor
4,691
3,633
Ranunculus - buttercup - does that refractive trick, too. If you hold the flower about a few cm under your chin (no beards allowed) and have the sun hit the flower you get a bright yellow splot of light. The yellow splot is a somewhat different color of yellow - so I am told. This is a 'folk' test to see if you like butter. Hence, buttercup, the common name. Looking at the petals: the upper surface has a 'shiny' coating and if you move the flower around you get some color changes.

As a wild guess this must be adaptive for attracting pollinators.
PS: splot is a highly scientific term which has a very specialized meaning, closely related to blotch and blob. :biggrin:
 
  • #12
Suyash Singh
168
1
So you all are saying that colours are different for different animals.
Thus i ask this question
What is the actual color of something?
 
  • #13
berkeman
Mentor
64,193
15,441
What is the actual color of something?
Remember, we don't discuss philosophy at the PF. Thanks.
 
  • Like
Likes Suyash Singh
  • #14
Suyash Singh
168
1
Remember, we don't discuss philosophy at the PF. Thanks.
I was asking for the scientific answer.
Like what is the actual color of something because if we are seeing that object it is being perceived by us as another color.
 
  • #15
jim mcnamara
Mentor
4,691
3,633
Unlikely IMHO, bougainvillea is either a bush or [v]ine and wouldn't make sense planted in a flower garden directly on the flat ground.

@Borek is correct, plus that family of species requires a warm climate, and is not frost tolerant.
 
  • #17
jim mcnamara
Mentor
4,691
3,633
@Suyash Singh there is no good scientific answer. Don't believe me? check this out: https://en.wikipedia.org/wiki/Synesthesia
Hearing sounds can cause a color vision response. We already have several threads on this topic so let's not for for a deep dive into synesthesia, just go lookup those threads. See? we are diverging already...
 
  • Like
Likes BillTre and Suyash Singh
  • #18
OmCheeto
Gold Member
2,265
2,741
Thanks Om! Awesome stuff. So you're saying I'm not crazy after all? o0)
Interesting comment.
I wonder how many scientific discoveries are held back by the observer saying to themselves; "I think I see something odd here, but it might be a hallucination, so I won't mention it, lest people think I'm crazy."

I'm pretty sure this is why I've never mentioned my observations of Rose Campions before today.

I mentioned an observation of infrared light one day on Facebook, and everyone was silent.
I therefore assumed I was crazy.
Though, my camera caught it also, so I don't think I'm totally crazy.

what.the.heck.is.with.me.seeing.uv.q.mark.png

Spectrum cast by the sun through my fish tank on Halloween last year.

ps. I wonder if getting married has an effect on what people are "allowed" to observe?
"It's ok to look at flowers, dear. You'll still be the man in my life."

hmmmm...
 

Attachments

  • what.the.heck.is.with.me.seeing.uv.q.mark.png
    what.the.heck.is.with.me.seeing.uv.q.mark.png
    27 KB · Views: 595
  • #19
BillTre
Science Advisor
Gold Member
2022 Award
2,219
7,367
There is also the issue of what "color" a colorblind person will see (meaning experience internally).
There are many different kinds of colorblindness in humans because you can lack or have impaired function of any combination of the different color receptors.
This can be tested and demonstrated in many ways, however, its not clear how to describe to a non-colorblind person what something looks like (internally) to a colorblind person.
Other species would seem to present even greater problems.
 
  • Like
Likes pinball1970
  • #20
jim mcnamara
Mentor
4,691
3,633
@OmCheeto before you consider "crazy" as answer try tetrachromacy. http://discovermagazine.com/2012/jul-aug/06-humans-with-super-human-vision
This is an edgy concept, and only one tetrachomat (female humans only allowed in this group, as of now) has been found per the article. At least two steps better than crazy, maybe. Virtually all of the rest of us use different cone cell types, 3 - versions, to create normal color vision. Color blindness means missing or defective cone types.

Tetrachromacy means that a tetrachromat can differentiate among 1004 colors whereas the rest of us dull thuds with color vision only see about 1 million colors 1003.

Of course mantis shrimp are beyond the pale - they are dodecachromats - they have color vision based on 12 cone cell variants, we have 3 (or maybe 4 sometimes). We hit the Twilight Zone of known Science of vision on this one.

Here is why:
https://onlinelibrary.wiley.com/doi/abs/10.1002/scin.5591820609 Apparently they do not see color the way we do. Read the article, please. I'll "flub" the explanation.

Mantis shrimp are beyond cool in several ways - outre vision, 10400g acceleration of the hunting club - among them
https://en.wikipedia.org/wiki/Mantis_shrimp.
with an acceleration of 10,400 g (102,000 m/s2 or 335,000 ft/s2) and speeds of 23 m/s (83 km/h; 51 mph) from a standing start.

They can break heavy aquarium glass, and make burrows into coral by "sledgehammering".
 
  • Like
Likes OmCheeto and BillTre
  • #21
pinball1970
Gold Member
1,616
2,244
Anyways, after some more googling, I also discovered a new discovery:

Petals produce a 'blue halo' that helps bees find flowers
Date: October 18, 2017
Source: University of Cambridge
Summary: Latest research has found that several common flower species have nanoscale ridges on the surface of their petals that meddle with light when viewed from certain angles.​

That's just 6 months ago!

I have to admit, I've never noticed this "Blue halo" before.
Though, I have noticed that Rose Campions catch my eye, in a weird "That plant is doing something to light that I can't describe." kind of way. (First noticed this around 1990.)
No other flower I've ever seen does it like it does.

I have seen something like this with that specific colour area on textiles for a quite a few years. Very bright bluish red shades at first I thought the dyeing was unlevel as I could distinctly see blue areas as well as red but the areas changed when I manipulated the fabric. After seeing this a few times I assumed it was some sort of optical effect. Textured surfaces only, this could explain it.
 
  • #22
pinball1970
Gold Member
1,616
2,244
There is also the issue of what "color" a colorblind person will see (meaning experience internally).
There are many different kinds of colorblindness in humans because you can lack or have impaired function of any combination of the different color receptors.
This can be tested and demonstrated in many ways, however, its not clear how to describe to a non-colorblind person what something looks like (internally) to a colorblind person.
Other species would seem to present even greater problems.

I have tested a few colour blind people and its quite weird watching them describe what they see when you are looking at the same images.
 
Top