Evolution of Black(ish) Flowers?

I understand there are no black flowers in nature, but there are some very, very dark flowers, like the one I linked to (and probably misidentified).

What are the evolutionary circumstances that would select for this?

What are the challenges and what are the benefits of having black-ish flowers, and what kind of environment supports this adaptation? Do dark flowers absorb more heat and does temperature control become difficult?

I’m posting here because a google search did not provide me with the information I was looking for. Thanks in advance if you can shed some light on my question…

https://www.inaturalist.org/observations/163498974

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I think most pollinators like bees, moths, and birds, gravitate towards bright non-green flowers, especially yellow for insects, white for nighttime pollinators like many moths, red for birds. I don’t think there is a pollinator that gravitates towards black flowers, so flowers that are very dark probably struggle to reproduce. One semi-exception is fly pollinated carrion plants are often dark brown like rotting meat, though not black.

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The linked one looks like a cultivated plant too.

Plants need pollinated to survive as a species, so they have to be on the spectrum that animals that pollinate, see. This doesn’t mean just visible light (defined by our human eyes), either. Try researching about that some you may find answers there.

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People. Horticulture brings shiny new bling, because people choose to buy it.
https://www.sapeople.com/2023/05/23/south-african-plant-wins-at-chelsea-flower-show-agapanthus-blackjack/

A few years ago it was a white Protea cynaroides that won.

So are you saying dark flowers exist only through artificial selection?

I am curious whether we can come up with examples of ones naturally that color. Personally most of the dark flowers I can think of are obvious horticultural selections, although there are some members of the bromeliad family with bright pink bracts and dark purple flowers, such as
https://www.inaturalist.org/taxa/552199-Puya-venusta
https://www.inaturalist.org/taxa/141279-Tillandsia-ionantha
https://www.inaturalist.org/taxa/846492-Wallisia-cyanea

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https://www.inaturalist.org/taxa/431150-Iochroma-cyaneum is pretty dark, nothing like “black” cultivars though.

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early blue cohosh has almost-black flowers too. It blooms very early right after snow is melting so perhaps the dark colors relate to chemicals that protect from frost, and given it’s so early its pollinator is probably pretty specialized and there isn’t a lot of competition (or early insects take anything they can get)
https://www.inaturalist.org/taxa/127920-Caulophyllum-giganteum

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Oh I like that one. Makes me think of https://www.inaturalist.org/taxa/56793-Fritillaria-biflora

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yes! i love chocolate lily.

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Yum, chocolate!

Penstemon whippleanus flowers can be a very dark shade of purple

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There’s Stapelia grandiflora, the carrion flower, which is pollinated by flies.

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This species comes pretty close, and there are several completely black orchid hybrids (artificially selected and bred of course).
Here’s one that I have

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One black flower - Nature Talk - iNaturalist Community Forum

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One lesson iNat has taught me. Never say never. There will be a niche, and a flower, which reaches its pollinator with a black (to our eyes) flower.

Found 2 via google

https://www.inaturalist.org/observations?place_id=any&taxon_id=362404

https://www.inaturalist.org/observations?place_id=any&taxon_id=343837

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I did have read that the colours human eyes percieve might not be same for other animals (here in this case, for pollinators of black flowers).

The flower might rely on self pollination more than relying upon other pollinating agents, this may be the reason for the presence of “unattractive” black colour of flower.
Also, there could be some pollinators like bats who have poor sense of vision, so the flower don’t have to be “visually” attractive.

oh we know it’s not the same

there’s a bbc/david attenborough special about animal vision, i think I watched it on disney+ if you want a high level overview with amazing videography

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Certain specimens of Arisaema triphyllum have almost black flowers, though there is massive variation across their range

(https://plants.ces.ncsu.edu/plants/arisaema-triphyllum/)

Also there’s Arum palaestinum, which is in the same family as A. triphyllum, so I wonder if there’s a connection?

And another I found, Fritillaria persica has almost-black flowers too.

https://en.wikipedia.org/wiki/Fritillaria_persica#/media/File:Fritillaria_persica_inflorescence.jpg

And i know there’s a few species of wild hellebore that are black, at least, in part, which is probably why its so easy to find fully black cultivated hellebores

EDIT: Thought of another one - certain Trilliums are so dark red that they almost look black in the right lighting. Given that they’re understory spring ephemerals, that right lighting isn’t too uncommon

image
https://www.wildflower.org/gallery/result.php?id_image=75195

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There are certainly some wild flowers that are so dark purple that to our eyes, they look black. I have also wondered what pollinates them, but this tends to be an area that needs more research. There are many plants that have been named as species but where no one has yet studied their pollination biology.
I have a project called “Fantastic Flowers” ( https://www.inaturalist.org/projects/fantastic-flowers ) where I collect flower observations that strike me as cool, and there are several species with nearly black flowers included.
In some cases, the black may provide a contrasting tone to help catch the eyes of pollinators, such as in this poppy:
https://www.inaturalist.org/observations/43489141
or in this bromeliad:
https://www.inaturalist.org/observations/35528031
Keep in mind, also, that these flowers may have scents or markings invisible to our eyes (infrared, UV) that may also help draw in pollinators. There are even some bat-pollinated flowers where the shape helps with echolocation.

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