Explanation: Stars shine and satellites glint in this clear, dark, night sky over Wannon Falls Reserve, South West Victoria, Australia. In fact the fuzzy, faint apparition above the tree tops is the only cloud visible, also known as the Large Magellanic Cloud, satellite galaxy of our own Milky Way. In the foreground, an Omphalotus nidiformis (ghost fungus) from planet Earth shines with a surprisingly bright bioluminescence. Like the Magellanic cloud, the ghost fungus was easily seen with the eye. Its ghostly glow was actually a dull green, but it appears bright green in digital camera picture. Two images were blended to create the scene. One focused on the distant stars and Large Magellanic Cloud some 160,000 light-years away. Another was focused on the foreground and glowing fungus several light-nanoseconds from the camera lens.
It is easy to think of evolution as only being about benefits, but in order for something beneficial to be naturally selected it must first arise spontaneously. The fact that plants have not so far evolved bioluminescence does not indicate a lack of benefit. It simply means that they have not stumbled upon a way of doing so.
Some bioluminescent organisms do not have any obvious benefit from their light. For some it is apparently a side effect rather than a useful trait - of interest to us but of no consequence to them. For example bioluminescent fungi (http://en.wikipedia.org/wiki/List_of_bi ... cent_fungi) are sometimes hypothesised to use the light to attract grazers to the fruiting bodies, other times hypothesised to use the light to repel grazers from the mycelium, these apparently contradictory hypotheses seeming somewhat inconclusive. However, the chemical used to produce the luminescence works by being oxidised, which means it acts as an antioxidant. The linked page on bioluminescent fungi mentions research suggesting that the production of the chemical is linked to the metabolism, and that it may provide:
antioxidant protection against the potentially damaging effects of reactive oxygen species produced during wood decay
So the fact that humans are sensitive to the particular light emitted may not be relevant to the benefit it provides as an antioxidant. As octern points out in the comments on this answer, the term for such byproducts independent of natural selection is spandrel (https://en.wikipedia.org/wiki/Spandrel_(biology)).
So, bioluminescence may have no direct evolutionary benefit and instead be only a side effect that doesn't have any evolutionary disadvantage.
Re: APOD: Ghost Fungus to Magellanic Cloud (2020 May 23)
Posted: Sat May 23, 2020 2:38 pm
by Chris Peterson
tmcdanel wrote: ↑Sat May 23, 2020 11:37 am
What could possibly be the survival advantage of bioluminescence for a fungal organism?
The bioluminescence is around the gills and cap, and it's suggested that it may attract insects important to the dispersal of spores.
That said, not every feature provides a survival ("fitness" is a better word) advantage. Many are neutral. The components that are involved in bioluminescence are closely related to those found in important metabolic pathways, so it's possible that their function is unrelated to bioluminescence and that is merely an accident of chemistry.
Re: APOD: Ghost Fungus to Magellanic Cloud (2020 May 23)
Explanation: Stars shine and satellites glint in this clear, dark, night sky over Wannon Falls Reserve, South West Victoria, Australia. In fact the fuzzy, faint apparition above the tree tops is the only cloud visible, also known as the Large Magellanic Cloud, satellite galaxy of our own Milky Way. In the foreground, an Omphalotus nidiformis (ghost fungus) from planet Earth shines with a surprisingly bright bioluminescence. Like the Magellanic cloud, the ghost fungus was easily seen with the eye. Its ghostly glow was actually a dull green, but it appears bright green in digital camera picture. Two images were blended to create the scene. One focused on the distant stars and Large Magellanic Cloud some 160,000 light-years away. Another was focused on the foreground and glowing fungus several light-nanoseconds from the camera lens.
orin stepanek wrote: ↑Sat May 23, 2020 12:09 pm
IMG_1478-Edit1200.jpg
Yes The SMC is there; also a couple of meteor streaks
as well!
I loved the Silhouette of the large tree also!
Meteors or satellites? The description starts with "Stars shine and satellites glint"...
I stand corrected!
Re: APOD: Ghost Fungus to Magellanic Cloud (2020 May 23)
Posted: Sat May 23, 2020 7:09 pm
by MarkBour
johnnydeep wrote: ↑Sat May 23, 2020 2:15 pm
... Meteors or satellites? The description starts with "Stars shine and satellites glint"...
Yes, I see three "streaks" in the image. Two bright ones, and one fainter one nearer the LMC (visible in the linked higher-res image). Meteor streaks generally have a shape with pointed ends and a much brighter middle, and also often show color variations. I can't say much about the faint streak, but for the two bright streaks, they appear much more steady than meteor streaks. Of course even a satellite streak, which I assume is made by reflection of sunlight, can vary over time, as its orbital movement changes what it is reflecting to the camera. I note that the brightest and longest streak appears somewhat brighter in its middle than at its ends. (Has anyone ever captured an image of a satellite that varied as the satellite itself rotated and changed brightness in a periodic fashion?)
Other thoughts: As I look at the ghost fungi, I see that the light from the fungi brightens the grass near them. So, we've got a reflection nebula around them. It's rare to see a green reflection nebula. And I wonder what the fungi *really* look like right now. It's unfortunate that we can only ever see them as they appeared several nanoseconds ago. For all we know, in the time it has taken the light to reach the camera ... (Okay, I apologize.)
One last thought, no longer joking: As I look at the stars in this lovely image, the sky around them appears in some patches more of a deep purple, and in other patches more of a plain black or gray. What causes that variation?
Re: APOD: Ghost Fungus to Magellanic Cloud (2020 May 23)
Posted: Sat May 23, 2020 7:17 pm
by Chris Peterson
MarkBour wrote: ↑Sat May 23, 2020 7:09 pm
Of course even a satellite streak, which I assume is made by reflection of sunlight, can vary over time, as its orbital movement changes what it is reflecting to the camera. I note that the brightest and longest streak appears somewhat brighter in its middle than at its ends. (Has anyone ever captured an image of a satellite that varied as the satellite itself rotated and changed brightness in a periodic fashion?)
I've caught tumbling or rotating satellites many times in images. They're quite common. Common visually, as well.
Re: APOD: Ghost Fungus to Magellanic Cloud (2020 May 23)
Posted: Sun May 24, 2020 1:02 am
by neufer
A mutualistic relationship with insects past (or present)
https://en.wikipedia.org/wiki/Fungus#Evolution wrote:
<<Many insects also engage in mutualistic relationships with fungi. Several groups of ants cultivate fungi in the order Agaricales as their primary food source, while ambrosia beetles cultivate various species of fungi in the bark of trees that they infest. Likewise, females of several wood wasp species (genus Sirex) inject their eggs together with spores of the wood-rotting fungus Amylostereum areolatum into the sapwood of pine trees; the growth of the fungus provides ideal nutritional conditions for the development of the wasp larvae. At least one species of stingless bee has a relationship with a fungus in the genus Monascus, where the larvae consume and depend on fungus transferred from old to new nests. Fungi ingrowing dead wood are essential for xylophagous insects (e.g. woodboring beetles). They deliver nutrients needed by xylophages to nutritionally scarce dead wood. Thanks to this nutritional enrichment the larvae of woodboring insect is able to grow and develop to adulthood.>>
Re: APOD: Ghost Fungus to Magellanic Cloud (2020 May 23)
johnnydeep wrote: ↑Sat May 23, 2020 2:15 pm
... Meteors or satellites? The description starts with "Stars shine and satellites glint"...
Yes, I see three "streaks" in the image. Two bright ones, and one fainter one nearer the LMC (visible in the linked higher-res image).
And now that you've pointed out that one that I missed, I see an even fainter, shorter streak about three inches down and to the left of your faint one in the high-res image!
All Hail to our Sourdough Overlords!
Posted: Sun May 24, 2020 3:19 pm
by neufer
https://en.wikipedia.org/wiki/Fungus#Evolution wrote:
<<A fungus (plural: fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, which is separate from the other eukaryotic life kingdoms of plants and animals. The earliest fossils possessing features typical of fungi date to the Paleoproterozoic era, some 2,400 million years ago (Ma); these multicellular benthic organisms had filamentous structures capable of anastomosis. In May 2019, scientists reported the discovery of a fossilized fungus, named Ourasphaira giraldae, in the Canadian Arctic, that may have grown on land a billion years ago, well before plants were living on land.
Some time after the Permian–Triassic extinction event (251.4 Ma), a fungal spike (originally thought to be an extraordinary abundance of fungal spores in sediments) formed, suggesting that fungi were the dominant life form at this time, representing nearly 100% of the available fossil record for this period. 65 million years ago, immediately after the Cretaceous–Paleogene extinction event that famously killed off most dinosaurs, there is a dramatic increase in evidence of fungi, apparently the death of most plant and animal species leading to a huge fungal bloom like "a massive compost heap".>>
<<As the coronavirus has taken hold and shut down our lives, we’ve taken to baking more. First the shortages were felt in flour, where you couldn’t get a bag of any type for love nor money. And once the newly-minted home bakers of the country hoovered up all the flour, they came back for the yeast. Three-quarters of a million more Brits bought yeast compared with the same period last year.
The overwhelming majority of yeast produced in the UK is fresh yeast, either in a cake or cream form. You take a batch of diluted molasses and seed it with the strain of yeast you want depending on its use and the climate in which most of it will be used. The yeast multiplies in giant vats, and becomes a concentrated slurry of yeast cells – the cream. Some modern industrial bakeries prefer their yeast in this form, while artisan commercial bakers prefer “cake” yeast, where the slurry is filtered and packed into supple blocks. Supermarkets hate fresh yeast because of its short shelf life and its difficulty in storage. So they want dry yeast.
Click to play embedded YouTube video.
The yeast is being produced,” he’s quick to point out. “But all of a sudden the market is being hit by demand from household customers to bake their own bread. Scarcity on the shelves has driven people to desperate measures. Searches for the phrase “yeast for bread” have increased more than 1,000 per cent in the last 30 days. Several sellers who appeared to be capitalising on the rarity of yeast in the current market, selling 25g packets of yeast for £3.39, a 900 per cent markup on supermarket yeast packet prices, did not respond to requests to speak for this story.
“Call it supply and demand, or profiteering, some online sellers are asking ridiculous money for flour and dried yeast,” says Chris Young of the Real Bread Campaign. Yet this hasn't stopped people from buying yeast. More than 560 people have purchased the overpriced yeast from this seller on eBay, and internal metrics at the online auction site suggest that more than 500 people are viewing the listing every day.
There are other options, of course. You can make a sourdough starter – or buy one, if you’re unable to mix flour and water together. Dried fruit also works, providing natural sugars to culture strains of yeast. If you’re desperate, soda bread can be made with buttermilk, flour and baking powder, and takes a fraction of the time. Or if you find some old yeast at the back of the cupboard that seems out of date, don’t throw it out – that stuff is gold dust.>>
Re: APOD: Ghost Fungus to Magellanic Cloud (2020 May 23)
MarkBour wrote: ↑Sat May 23, 2020 7:09 pm
Yes, I see three "streaks" in the image. Two bright ones, and one fainter one nearer the LMC (visible in the linked higher-res image).
And now that you've pointed out that one that I missed, I see an even fainter, shorter streak about three inches down and to the left of your faint one in the high-res image!
What does “three inches” mean in the context of various display devices of various sizes?
Re: APOD: Ghost Fungus to Magellanic Cloud (2020 May 23)
MarkBour wrote: ↑Sat May 23, 2020 7:09 pm
Of course even a satellite streak, which I assume is made by reflection of sunlight, can vary over time, as its orbital movement changes what it is reflecting to the camera. I note that the brightest and longest streak appears somewhat brighter in its middle than at its ends. (Has anyone ever captured an image of a satellite that varied as the satellite itself rotated and changed brightness in a periodic fashion?)
I've caught tumbling or rotating satellites many times in images. They're quite common. Common visually, as well.
Thinking about it a little longer, I would think that most earth-orbiting missions would have reasons they would want to stabilize the satellites, so that (while actively operational) they would not tumble very much. At least for satellites that had enough asymmetry that their tumbling would change their visible aspect a lot as they passed overhead. I mean, it would be bad for solar collectors, earth-observing instruments, etc. if the satellite rotated too much. But if you've seen them, then there must be some that behave that way. It would be cool to see such tracks.
Re: APOD: Ghost Fungus to Magellanic Cloud (2020 May 23)
MarkBour wrote: ↑Sat May 23, 2020 7:09 pm
Of course even a satellite streak, which I assume is made by reflection of sunlight, can vary over time, as its orbital movement changes what it is reflecting to the camera. I note that the brightest and longest streak appears somewhat brighter in its middle than at its ends. (Has anyone ever captured an image of a satellite that varied as the satellite itself rotated and changed brightness in a periodic fashion?)
I've caught tumbling or rotating satellites many times in images. They're quite common. Common visually, as well.
Thinking about it a little longer, I would think that most earth-orbiting missions would have reasons they would want to stabilize the satellites, so that (while actively operational) they would not tumble very much. At least for satellites that had enough asymmetry that their tumbling would change their visible aspect a lot as they passed overhead. I mean, it would be bad for solar collectors, earth-observing instruments, etc. if the satellite rotated too much. But if you've seen them, then there must be some that behave that way. It would be cool to see such tracks.
Some satellites do rotate by design, but most of those that we observe varying regularly in brightness have failed in some way, and are defunct and uncontrolled. There are a lot of those.
Re: APOD: Ghost Fungus to Magellanic Cloud (2020 May 23)
MarkBour wrote: ↑Fri May 29, 2020 5:24 am
Thinking about it a little longer, I would think that most earth-orbiting missions would have reasons they would want to stabilize the satellites, so that (while actively operational) they would not tumble very much.
Some satellites do rotate by design, but most of those that we observe varying regularly in brightness have failed in some way, and are defunct and uncontrolled. There are a lot of those.
Ghost Fungus to Magellanic Cloud
