The glowing ghost mushroom looks like it comes from a fungal netherworld



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The ghost fungus emits an eerie green glow.
Alison Pouliot, Author provided

Alison Pouliot, Australian National University

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It’s worth tolerating the mosquitoes and the disconcerting rustle of unseen creatures that populate forests after dark, for the chance to encounter the eerie pale green glow of a less-known inhabitant.

Australia is a land of extremes, of curious organisms with quirky adaptations. Even our ghosts are more perplexing than your regular spook, and you don’t need a Geiger counter or infrared camera to track them down. Ghosts feature fantastically in folklore across the globe, but Australia’s ghost collective has a special fungal addition. Stealing the limelight, or rather the twilight, is the ghost fungus, Omphalotus nidiformis.

Ghost fungi are large, common and conspicuous, yet they manage to escape the gaze of most. As interest in fungi grows in Australia, the ghost fungi is getting a curious new look-in.



The Conversation/Alison Pouliot

Fungi are well known for their perplexing traits and peculiar forms. One of the more mesmerising – and other-worldly – traits is luminosity. A conspicuous quirk, luminosity has been recognised for a good while. Aristotle (384–322 BC) was among the first to have reported terrestrial bioluminescence (bios meaning living and lumen meaning light) in the phenomenon of “glowing wood” or “shining wood” –luminescent mycelia in decomposing wood.

However, well before Aristotle’s time, Aboriginal Australians knew about the luminescence of fungi. Early settlers in Australia recorded the reactions of different Aboriginal groups to what we think was the ghost fungus. Some, such as the Kombumerri of southeastern Queensland, associated luminous fungi with evil spirits and supernatural activities of Dreamtime ancestors. West Australian Aboriginal people referred to the ghost fungus as Chinga, meaning spirit.

Ghost fungi often grow en masse in large overlapping clusters around the bases of both living and dead trees.
Alison Pouliot, Author provided

Similarly in Micronesia, some people destroyed luminous fungi believing them to be an evil omen, while others used them in body decoration, especially for intimidating enemies.

In California, miners believed them to mark the spot where a miner had died. This seemingly inexplicable glowing trait gave rise to rich and colourful folk histories.

Lighting up the night

The ghost fungus contains a light-emitting substance called luciferin (lucifer meaning light-bringing). In the presence of oxygen, luciferin is oxidised by an enzyme called luciferase. As a result of this chemical reaction, energy is released as a greenish light. The light from the ghost fungus is often subtle and usually requires quite dark conditions to see. To experience ghost fungi at their most spectacular you need to allow your eyes time to adjust to the darkness, and don’t use a torch.

Ghost fungi have been widely recorded across Australia, especially in the forests of the south-eastern seaboard. They often appear in large overlapping clusters around the bases of a variety of trees, commonly Eucalyptus, but also Acacia, Hakea, Melaleuca, Casuarina and other tree genera as well as understorey species.

The large funnel-shaped mushrooms (the reproductive part of the fungus) are variable in form and colour, but are mostly white to cream coloured with various shades of brown, yellow, green, grey, purple and black, usually around the centre of the cap. On the underside, the lamellae (radiating plates that contain the spores) are white to cream coloured and extend down the stipe (stem).

This adaptable fungus obtains its tucker as both a weak parasite of some tree species and as a saprobe, which means it gets nutrition from breaking down organic matter such as wood.

Young ghost fungi can appear remarkably similar to edible oyster (Pleurotus) mushrooms, but be warned, ghost fungi are toxic.
Alison Pouliot, Author provided

Although fungal bioluminescence has been well documented, little research has been done to establish why fungi go to the trouble of glowing. While some experiments have shown that bioluminescence attracts spore-dispersing insects to particular fungi, this appears not to be the case with the ghost fungus.

Researchers who tested whether insects are more readily attracted to the ghost fungus concluded that bioluminescence is more likely to be an incidental by-product of metabolism, rather than conferring any selective advantage.

Those who find this scientific explanation rather unimaginative might prefer to stick with the theory that these fungi help guide fairies (or perhaps a bilby or bandicoot) through the darkened forest.

If you stumble across ghost fungi in daylight, however, they look far less puzzling. It does bear a superficial resemblance to the delicious oyster mushroom (and were once classified in the same genus), but unfortunately they are toxic. Ghost fungi possess a powerful emetic that causes nausea and vomiting. (And who knows, it might even cause you to glow terrifyingly green…)

Returning to darkness

We live in the Age of Illumination, plagued by light pollution. Earth’s nights are getting brighter and many scientists are concerned about the effects on wildlife as well as how they stymie human appreciation of nature. Artificial lights disorient birds, especially those that migrate at night and other species such as hatching turtles that confuse artificial light with that of the moon. Exposure to artificial light also affects human health.

A nighttime wander through the forest reveals its nocturnal inhabitants and may reward one with the pleasures of finding ghost fungi. Only in darkness is their magic revealed.


Alison Pouliot will be launching her book on Australian fungi, The Allure of Fungi, in Melbourne, Daylesford, Apollo Bay and Shellharbour. For more details on these events go here.

Sign up to Beating Around the Bush, a series that profiles native plants: part gardening column, part dispatches from country, entirely Australian.The Conversation

Alison Pouliot, , Australian National University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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It’s fish on ice, as frozen zoos make a last-ditch attempt to prevent extinction


Nicola Marie Rivers, Monash University

Twenty-six of the forty-six fish species known to live in the Murray-Darling basin are listed as rare or threatened. Recent fish kills in the iconic river system are a grim reminder of how quickly things can take a turn for the worst.

A sudden drop in population size can push a species towards extinction, but there may be hope for resurrection. Frozen zoos store genetic material from endangered species and are preparing to make new individuals if an extinction occurs.




Read more:
Cryopreservation: the field of possibilities


Unfortunately, poor response to freezing has hindered the introduction of fish into frozen zoos in the past. Now new techniques may provide them safe passage.

Ice ice baby

A frozen zoo, also known as a biobank or cryobank, stores cryopreserved or “frozen” cells from endangered species. The primary purpose of a frozen zoo is to provide a backup of endangered life on Earth allowing us to restore extinct species.

Reproductive cells, such as sperm, oocytes (eggs) and embryos, are cooled to -196ºC, at which point all cellular function is paused. When a sample is needed, the cells are warmed and used in breeding programs to produce new individuals, or to study their DNA to determine genetic relationships with other species.

There are several cryobanking facilities in Australia, including the Australian Frozen Zoo (where I work), the CryoDiversity Bank and the Ian Potter Australian Wildlife Biobank, as well as private collections. These cryobanks safeguard some of Australia’s most unique wildlife including the greater bilby, the golden bandicoot, and the yellow-footed rock wallaby as well as other exotic species such as the black rhino and orangutans.

Internationally, frozen zoos are working together to build a “Noah’s Ark” of frozen tissue. The Frozen Ark project, established in 2004 at the University of Nottingham, now consists of over 5,000 species housed in 22 facilities across the globe.

The Manchurian trout, or lenok, is the only fish successfully reproduced through cryopreservation and surrogacy.
National Institute of Ecology via Wikimedia, CC BY

Less love for fish

As more and more species move into frozen zoos, fish are at risk of being left out. Despite years of research, no long-term survival has been reported in fish eggs or embryos after cryopreservation. However, precursors of sperm and eggs known as gonial cells found in the developing embryo or the ovary or testis of adult fish have been preserved successfully in several species including brown trout, rainbow trout, tench and goby.

By freezing these precursory cells, we now have a viable method of storing fish genetics but, unlike eggs and sperm, the cells are not mature and cannot be used to produce offspring in this form.

To transform the cells into sperm and eggs, they are transplanted into a surrogate fish. Donor cells are injected into the surrogate where they follow instructions from surrounding cells which tell them where to go and when and how to make sperm or eggs.

Once the surrogate is sexually mature they can mate and produce offspring that are direct decedents of the endangered species the donor cells were originally collected from. In a way, we are hijacking the reproductive biology of the surrogate species. By selecting surrogates that are prolific breeders we can essentially “mass produce” sperm and eggs from an endangered species, potentially producing more offspring than it would have been able to within its own lifetime.

Cell surrogacy has been successful in sturgeon, rainbow trout and zebrafish.

The combination of cryopreservation and surrogacy in conservation is promising but has only successfully been used in one endangered species so far, the Manchurian trout.

Not a get-out-of-conservation card

The “store now, save later” strategy of frozen zoos sounds simple but alas it is not. The methods needed to reproduce many species from frozen tissue are still being developed and may take years to perfect. The cost of maintaining frozen collections and developing methods of resurrection could divert funding from preventative conservation efforts.

Even if de-extinction is possible, there could be problems. The Australian landscape is evolving – temperatures fluctuate, habitats change, new predators and diseases are being introduced. Extinction is a consequence of failing to adapt to these changes. Reintroducing a species into the same hostile environment that lead to its demise may be a fool’s errand. How can we ensure reintroduced animals will thrive in an environment they may no longer be suited for?

Reducing human impact on the natural environment and actively protecting threatened species will be far easier than trying to resurrect them once they are gone. In the case of the Murray Darling Basin, reversing the damage done and developing policies that ensure its long-term protection will take time that endangered species may not have.




Read more:
I’ve always wondered: does anyone my age have any chance of living for centuries?


Frozen zoos are an insurance policy, and we don’t want to have to use them. But if we fail in our fight against extinction, we will be glad we made the investment in frozen zoos when we had the chance.The Conversation

Nicola Marie Rivers, PhD Candidate, Monash University

This article is republished from The Conversation under a Creative Commons license. Read the original article.