• Ultraviolet Photography
  •  

Floral or nectar guide references


8 replies to this topic

#1 DaveO

    Aussie Bunyip

  • Members(+)
  • 611 posts
  • Location: Maldon, Victoria, Australia

Posted 01 January 2015 - 05:03

While bumbling around (as you do) I followed this path. Has anyone else seen the last one which features some real "cut and paste" work on Rudbeckia?

Flavonols: pigments responsible for ultraviolet absorption in nectar guide of flower

http://www.ncbi.nlm..../pubmed/5050486

Formation of UV-honey guides in Rudbeckia hirta

http://www.ncbi.nlm....pubmed/19477473

Wild bees preferentially visit Rudbeckia flower heads with exaggerated ultraviolet absorbing floral guides

http://www.ncbi.nlm....pubmed/24585774

Full text

http://bio.biologist...nt/3/3/221.long

Happy New Year to all

Dave

#2 colinbm

    Member

  • Members(+)
  • 1,236 posts
  • Location: Australia

Posted 01 January 2015 - 05:31

Thanks Dave, Happy New Year to you too, that should be a great read.
Are these pictures credited anywhere ?
I can see one of our members mentioned in the References section.
What does ""some real "cut and paste" work"" mean please ?
Col

#3 nfoto

    Fierce Bear of the North

  • Owner-Administrator
  • 2,020 posts
  • Location: Sørumsand, Norway

Posted 01 January 2015 - 08:44

As a former botanist I'm amused by the contrast between the presented exact nomenclature of chemical compounds and the very sloppy description of the species under investigation. "Petals" indeed. My ears cringe.

The authors indeed used "cut and paste" by cutting off sections of the ligulate flowers and glueing them onto different flower heads. Clearly they - probably unknowingly - altered important aspects such as conical cell structures and other related optical properties, plus whatever change brought about by wilting. Thus one cannot exclude other, non-studied factors from having had effects in these experiments. They made nowhere in the paper any reference to the fact that pollinators visit the disk flowers not the ligulate ones and evidently had no control whatsoever as to the UV-related properties of the disk flowers in the studied populations.
Bjørn Birna Rørslett, Ph.D.
Just call me Birna

#4 Andrea B.

    Desert Dancer

  • Owner-Administrator
  • 6,441 posts
  • Location: USA

Posted 01 January 2015 - 17:22

Thanks, Dave, for the references. And there are lots of similar references on the right side. So several things to pursue.
(I was familiar with the first paper.)

Petal references and certain lack of control in the experiment aside, these are quite interesting papers because they identify the underlying pigments, etc. This is something I have been studying a bit - just now reading the book Nature's Palette - the Science of Plant Color by David Lee
which is an interesting overview but slightly "sketchy" on the explanations.

Bjørn, I would say that you continue to be a botanist - no 'former' about it.
Andrea G. Blum
Often found hanging out with flowers & bees.

#5 nfoto

    Fierce Bear of the North

  • Owner-Administrator
  • 2,020 posts
  • Location: Sørumsand, Norway

Posted 01 January 2015 - 18:45

Seeing the alarming rate at which my botanical insights deteriorate over the years, I prefer being known as "former botanist" ...
Bjørn Birna Rørslett, Ph.D.
Just call me Birna

#6 DaveO

    Aussie Bunyip

  • Members(+)
  • 611 posts
  • Location: Maldon, Victoria, Australia

Posted 02 January 2015 - 00:36

As a "former chemist" I can relate to that. I keep thinking how much I could do if I was still able to access all the gear we had in our labs.

I recently spent some time reading about bee vision from one of the papers that came up in Andrea's thread on Bee Vision, in particular the work of Adrian Horridge

What does the honeybee see? Adrian horridge

http://press.anu.edu...n/pdf-download/

A bit more digging gave this list of his many publications

http://adrian-horridge.org/

I now know why I felt drawn to his work, we were born perhaps 35 km apart in Yorkshire (that's where James Cook RN came from which began all this Australian thing).

He makes several well scattered comments that "The part played by UV receptors is little understood". I think he is a master of understatement. That made me feel better, perhaps there's something for me to do after all in this UV world.

Cheers,

Dave

#7 Andrea B.

    Desert Dancer

  • Owner-Administrator
  • 6,441 posts
  • Location: USA

Posted 02 January 2015 - 16:42

I will add to the lament - all those hours of studying mathematics and now I can barely remember how to find the derivative of such simple functions as f(x) = x2.

...perhaps there's something for me to do after all in this UV world.

Of course !!!

Some folks design the building.

Some folks lay the bricks and mortar.

Some folks carry the construction materials to the site.

All 3 efforts are needed to complete the structure, yes?? So I like to think that we are all contributing to the UV Building - perhaps in ways we cannot yet know.
Andrea G. Blum
Often found hanging out with flowers & bees.

#8 nfoto

    Fierce Bear of the North

  • Owner-Administrator
  • 2,020 posts
  • Location: Sørumsand, Norway

Posted 03 January 2015 - 00:44

Derivative of f(x)=x2 ==> 2x? if I remember correctly. Been a while.
Bjørn Birna Rørslett, Ph.D.
Just call me Birna

#9 Andrea B.

    Desert Dancer

  • Owner-Administrator
  • 6,441 posts
  • Location: USA

Posted 03 January 2015 - 17:28

yep.
perhaps I was exaggerating just a bit. :lol: :lol: :lol:
Andrea G. Blum
Often found hanging out with flowers & bees.