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Why blue animals are so rare

popsci.com

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Re: Why blue animals are so rare

#51

Post by jcynix »

spullara wrote: post #33
jcynix wrote: post #19

The article mentions plants too. But I can list a number of blue plants in my vicinity (OK, sometimes a touch of purple too) or even in the garden: [Centaurea cyanus]( https://en.wikipedia.org/wiki/Centaurea_cyanus?wprov=sfla1 ) [Digitalis]( https://en.wikipedia.org/wiki/Digitalis?wprov=sfla1 ) [Centaurea]( https://en.wikipedia.org/wiki/Centaurea?wprov=sfla1 ) [Scabiosa]( https://en.wikipedia.org/wiki/Scabiosa?wprov=…

3 of those I would call purple rather than blue.

I agree, but purple seems to be a similarly rare color IMO.

I could offer

[Chicory](https://en.wikipedia.org/wiki/Chicory?wprov=sfla1), [Myosotis](https://en.wikipedia.org/wiki/Myosotis?wprov=sfla1) and [Borage](https://en.wikipedia.org/wiki/Borage?wprov=sfla1)

as replacements ...

Re: Why blue animals are so rare

#52

Post by RoyalHenOil »

al_borland wrote: post #47
setopt wrote: post #46

Earlier quoted context omitted.

One of the best ways to improve crop yields via genetic engineering might be to create black plants.

If that was optimal, I would expect it would be the standard by now. Not through genetic engineer, but through basic evolution over millions of years.

That will only be the case if light absorbence is the primary limiting factor for the plant. If something else is a bigger limiting factor (e.g., nutrients, pests, water, temperature, pollinators, and so on), then a more darkly colored plant will not be meaningfully more likely to survive and reproduce than its lightly colored neighbors.

Outside of human-directed breeding, we typically only see darkly colored plants in locations with low light and with few other evolutionary pressures: deep understory tropical plants, for example.

Meanwhile, in locations with high light and other evolutionary pressures, plants can sometimes evolve to be quite pale. For example, desert succulents are often very light colors because they need to deflect light to keep cool and preserve water.

Re: Why blue animals are so rare

#53

Post by buzzm »

ianferrel wrote: post #50
al_borland wrote: post #47

Earlier quoted context omitted.

If that was optimal, I would expect it would be the standard by now. Not through genetic engineer, but through basic evolution over millions of years.

Evolution is optimizing for survival, not crop yield.

Exactly; see pollinators comment above. Although as tech progresses... perhaps we can make black plants as attractive to genetically modified pollinators. Do I sense a slippery slope here?

Re: Why blue animals are so rare

#54

Post by RoyalHenOil »

User23 wrote: post #41

There are also no blue pigments in any plant. The various blueish flowers use other tricks to reflect blue light.

To be fair, indigo is a blue pigment and it is present in many different plant species. (Mind you, it does not make the plant blue; it only becomes blue after exposure to oxygen.)

Re: Why blue animals are so rare

#55

Post by bawolff »

ianferrel wrote: post #50
al_borland wrote: post #47

Earlier quoted context omitted.

If that was optimal, I would expect it would be the standard by now. Not through genetic engineer, but through basic evolution over millions of years.

Evolution is optimizing for survival, not crop yield.

Having more energy available (all things being equal which they aren't) is advantous to both survival and crop yields.

Re: Why blue animals are so rare

#56

Post by knodi123 »

esafak wrote: post #23

On a related note, blue LEDs are also the most rare, for engineering reasons, and their production led to a Nobel Prize: https://www.nobelprize.org/prizes/physics/2014/press-release...

"...once Nakamura succeeded in creating a commercially viable prototype, 3 orders of magnitude (1000 times) brighter than previously successful blue LEDs, Nichia pursued developing the marketable product. The company's gross receipt surged from just over ¥20 billion (≈US$200 million) in 1993 to ¥80 billion (≈US$800 million) by 2001, 60 percent of which was accounted for by sales of blue LED products."

And IIRC, in return for that he got a $180 bonus from his employer, and a bit later, a Nobel prize.

Re: Why blue animals are so rare

#57

Post by lores »

dotancohen wrote: post #42
pvaldes wrote: post #39

Earlier quoted context omitted.

> "The only exception in nature is the obrina olivewing butterfly, which is the only known animal to produce a true blue pigment." That is a bold claim, but a false one. A few butterfly species share that pigment. Mussels also have other blue pigments based in carothenes that don't depend on iridiscence.

Also, there is a snail that was revered millennia ago for some blue ink that could be extracted from it. Several religions, notably Judaism among them because it is still around today, attach significance to this difficult-to-obtain colour.

That's the dye from Hexaplex Trunculus, but it's more of a bluish purple than a true blue. There seems to be modern ways to turn it into a true blue, but whether the ancients had an unknown method is debated and unproven. It's worth noting that colour names in ancient times were a lot more blurry than now (the famous sea the colour of wine of Homer), and blue is still one of the most blurry.

Re: Why blue animals are so rare

#59

Post by kokanee »

cubefox wrote: post #21
thrdbndndn wrote: post #6

Isn't it pretty common in marine animals? Lots of fish, dolphins, whales, etc. Or do they count as grey?

Only cartoon fish are blue.

There are two interesting cases of blue fish in my home state.

1. The Beardslee Trout, which exists only in a single lake in the world: https://en.wikipedia.org/wiki/Beardslee_trout. Most photos online of these fish, including the Wikipedia thumbnail, are not representative of the stunning color of these fish in person, and are most likely not Beardslees at all. The lake itself looks like blue gatorade, and the fish have obviously adapted accordingly.

2. Lingcod, a fraction of which are a crazy alien blue color not only outside but throughout the flesh. https://oregonmarinereserves.com/2021/08/31/lingcod/. This phenomenon applies to a handful of species, but lingcod is the most well-known.

Re: Why blue animals are so rare

#60

Post by esperent »

Are blue animals rare? They are certainly not that rare as a casual search turns up hundreds of photos of blue lizards, butterflies, Beatles, spiders, birds, starfish, fish, whales, sharks, and other miscellaneous sea and land creatures.
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