Mushrooms to Mars: how fungi research could help long-duration space travel

I've often noted that fungi are the forgotten heroes of the ecosystem, beavering away largely out of sight and therefore out of mind. Whether it's the ability to break down plastic waste or their use as meat substitutes and pharmaceuticals, this uncharismatic but vital life form no doubt hold many more surprises in store for future research to discover. It's estimated that less than ten percent of all fungi species have so far been scientifically described; it's small wonder then that a recent study suggests an entirely new use for several types of these under-researched organisms.

Investigation of the Chernobyl nuclear power station in 1991 found that Cladosporium sphaerospermum, a fungus first described in the late nineteenth century, was thriving in the reactor cooling tanks. In other words, despite the high levels of radiation, the species was able to not only repair its cells but maintain a good rate of growth in this extreme environment. This led to research onboard the International Space Station at the end of 2018, when samples of the fungus were exposed to a month of cosmic radiation. The results were promising: a two millimetre thick layer of the fungus absorbed nearly two percent of the radiation compared to a fungus-free control.

This then suggests that long-duration crewed space missions, including to Mars, might be able to take advantage of this material to create a self-repairing radiation shield, both for spacecraft and within the walls of surface habitats. A twenty-one centimetre thick layer was deemed effective against cosmic rays, although this could potentially be reduced to just nine centimetres if the fungal mycelia were mixed with similar amounts of Martian soil. In addition, there is even the possibility of extracting the fungus' radiation-proof melanin pigment for use in items that require much thinner layers, such as spacesuit fabric.

If this sounds too good to be true, there are still plenty of technological hurdles to be overcome. Science fiction has frequently described the incorporation of biological elements into man-made technology, but it's early days as far as practical astronautics is concerned. After all, there is the potential for unique dangers, such as synthetic biology growing unstoppably (akin to scenarios of runaway nanobot replication). However, NASA's Innovative Advanced Concepts program (NIAC) shows that they are taking the idea of fungi-based shielding seriously, the current research considering how to take dormant fungal spores to Mars and then add water to grow what can only be described as myco-architecture elements - even interior fittings and furniture. In addition to the radiation shielding, using organic material also has the advantage of not having to haul everything with you across such vast distances.

Even more ideas are being suggested for the use of similarly hardy species of fungi on a Mars base, from bioluminescent lighting to water filtration. Of course, this doesn't take into account any existing Martian biology: the seasonal methane fluctuations that have been reported are thought by some to be too large to have a geochemical cause; this suggests that somewhere in the sink holes or canyon walls of Mars there are colonies of methane-producing microbes, cosily shielded from the worst of the ultraviolet. If this proves to be the case, you would hope that any fungi taken to the red planet would be genetically modified to guarantee that it couldn't survive outside of the explorer's habitats and so damage Martian biota. Humanity's track record when it comes to preserving the ecosystems of previously isolated environments is obviously not something we can be proud of!

What fungi can do alone, they also do in symbiosis with algae, i.e. as lichens. Various experiments, including the LIchens and Fungi Experiment (LIFE) on the International Space Station (incidentally, doesn't NASA love its project acronyms?) have tested extremophile lichens such as Xanthoria elegans and Rhizocarpon geographicum in simulated Martian environments for up to eighteen months. The researchers found that the organisms could remain active as long as they were partially protected, as if they were growing in sink holes beneath the Martian surface. Of course, this success also enhances the possibility of similar lifeforms already existing on the red planet, where it would have had eons in which to adapt to the gradually degraded conditions that succeeded Mars' early, clement, phase.

The CRISPR-Cas9 system and its successors may well develop synthetic fungi and lichens that can be used both on and especially off the Earth, but we shouldn't forget that Mother Nature got there first. Spacecraft shielding and myco-architecture based on natural or genetically modified organisms may prove to be an extremely efficient way to safeguard explorers beyond our world: the days of transporting metal, plastic and ceramic objects into space may be numbered; the era of the interplanetary mushroom may be on the horizon. Now there's a phrase you don't hear every day!

Fundamental fungi: the forgotten kingdom vital to our future

At the end of 1993 the Convention on Biological Diversity came into force. A key piece of global legislation in the promotion of sustainable development, it marked a change in focus for environmental concerns. Whereas previous high-profile conservation efforts such as those of the World Wide Fund for Nature or Greenpeace were frequently aimed at individual species or regional ecosystems, the legislation initiated by the 1992 Earth Summit in Rio de Janeiro was aimed at the biota of the entire planet. However, there are still segments of enormous ecological importance that are lacking sufficient research.

I've previously discussed how little attention general-readership natural history pays to the kingdom of fungi, which may have somewhere between 1.5 million and 3.8 million species. Of these, less than 150,000 have been scientifically described. Clearly, this is one life form where our knowledge barely covers the tip of the iceberg. It's hardly as if this attitude is a new one, either. While Linnaeus produced comprehensive editions on plant and animal taxonomy in the 1750s, it took over seventy years for anyone to bother with fungi: it wasn't until 1821 that another Swedish naturalist, Elias Magnus Fries, produced an equivalent work called Systema Mycologicum.

Thanks to the majority of fungal material living either underground or in dark, damp environments such as leaf litter, the kingdom fails to get the attention it deserves. Even the forms we see more regularly, such as mushrooms and symbiotic lichen, engender little interest. Many people no doubt still mistake the former as plants - and are scared off any interest in the wild forms due to the dangers of poisonous species - while the latter are rarer in polluted, i.e. urban, environments and fail to compete in sight and scent with the glories of the flowering plants.

In the eight years since I wrote about the lack of interest in fungi, I've found reason to mention the long-forgotten kingdom in various important contexts. For a start, numerous animals and plants are becoming critically endangered due to fungal pathogens accidentally being spread by global travel. In addition, research over the past three years has shown that Aspergillus tubingensis and several other types of fungi show promise as a bio-friendly solution to plastic waste. Finally, last month I looked at non-animal protein substitutes, including the mycoprotein-derived Quorn.

Despite the potential of these various forms of fungi, the organism's losses due to rapid environmental changes don't appear to be garnering much attention. The IUCN Red List, which tabulates the differing levels of threat faced by all life on Earth, only shows 343 fungi as currently endangered; this contrasts with over 43,000 plants and 76,000 animals on the list. Undoubtedly, the Kingdom Fungi is being given an underwhelming amount of attention just as we are discovering how important it is to maintaining ecosystem stability and for the future of our species.

Recently published reports of studies conducted in the Amazon region show that deforestation has a long-term impact on soil biota, which in turn affects the entire local ecology. Studies of a range of habitats, such as primary forest, agricultural land (including monoculture), pasture/grazing, forestry plantations and secondary/regenerated forest showed that although overall fungal mass might remain consistent, species diversity is far lower outside of the original rainforest. The lack of fungal variety was linked directly to the lack of plant diversity in those biomes, with recovery a slow or unlikely prospect due to the newly-fragmented nature of the landscape preventing efficient dispersal of fungal spores.

There are some obvious points that agribusiness seems to ignore, such as the effects of pesticides and fertilisers on local fungi and the loss of microhabitats vital to maintaining a healthy variety of fungal species. If only more generalist fungi can survive the change in land use from the wonderful diversity of the rainforest (with up to 400 fungal species per teaspoonful) then this may have repercussions for future farming. As an example, the fungus Fusarium oxysporum has a phytopathogenic effect on agricultural plants including palm oil, but without competition from a wider cross-section of fungi (for example, Paraconiothyrium variabile) it could spread rapidly within a dismal monoculture environment. 

As a predominantly visual species, we humans are unthinkingly biased about the natural world based upon what we see: think cute giant panda versus the unappealing aesthetics of the blobfish. It really is a case of out of sight, out of mind, but unfortunately no amount of spin doctoring will make fungi as much loved as furry mammals. Yet our attitudes need to change if we are to maintain the delicate ecological balance; fungi are highly important for recycling nutrients, regulating carbon dioxide levels, and as a source of food and pharmaceuticals. Yet they remain the soil equivalents of the ubiquitous underwater copepods, unsung heroes of the global ecosystem. It's about time we took a lot more notice of this forgotten kingdom.

Defrosting dangers: global warming and the biohazards under the ice

Despite frequent news reports on the thawing of polar and glacial ice, there appears to be less concern shown towards this aspect of climate change than many others. Perhaps this is due to so few humans living in these regions; lack of familiarity with something helps us to ignore its true importance. The most obvious effects of melting ice are said to be the increase in atmospheric carbon, rising sea levels and unpredictable weather patterns, but there is another threat to our species that is only just beginning to be noticed - and as yet has failed to generate any mitigation plans.

A report last year confirmed a frightening cause behind the deaths back in 2015 of approximately half the world's remaining saiga antelope population: thanks to warmer and more humid weather, a type of bacteria usually confirmed to their nose had spread to the antelopes' bloodstream. Although not the sort of news to attract much attention even from nature-lovers, this ecological David and Goliath scenario looks set to be repeated in colder environments around the globe. Microscopic and fungal life forms that have been trapped or dormant for long periods, possibly millennia, may be on the verge of escaping their frozen confines.

The various film adaptions of John W. Campbell's 1938 novella Who Goes There? show the mayhem caused by an alien organism that has escaped its icy tomb. The real-life equivalents to this fictional invader are unlikely to be of extra-terrestrial origin, but they could prove at least as perilous, should climate change allow them to thaw out. The problem is easy to state: there is an enormous amount of dormant microbial life trapped in ice and permafrost that is in danger of escaping back into the wider ecosystem.

In the first quarter of the Twentieth Century over a million reindeer were killed by anthrax, with subsequent outbreaks occurring sporadically until as late as 1993. Recent years have seen the death of both farmers and their cattle from infection related to the thawing of a single infected reindeer carcass. In various incidents in 2016, dozens of Siberian herders and their families were admitted to hospital while Russian biohazard troops were flown in to run the clean-up operations. One issue is that until recently the infected animals - domesticated as well as wild - have rarely been disposed of to the recommended safety standards. Therefore, it doesn't take much for reactivated microbes to spread into environments where humans can encounter them.

Of course, the numbers of people and livestock living near glaciers and the polar caps is relatively low, but there are enormous regions of permafrost that are used by herders and hunters. Meltwater containing pathogens can get into local water supplies (conventional water treatment doesn't kill anthrax spores), or even reach further afield via oceans - where some microbes can survive for almost two years. The record high temperatures in some of the Northern Hemisphere's permafrost zones are allowing the spread of dangerous biological material into regions that may not have seen them for centuries - or far longer.

Decades-old anthrax spores aren't the only worry. Potential hazards include the smallpox virus, which caused a Siberian epidemic in the 1890s and may be able to survive in a freeze-dried state in victim's corpses before - however unlikely - reviving due to warmer temperatures. In addition, it should be remembered that many of the diseases that infect Homo sapiens today only arose with the development of farming, being variants of bacteria and viruses that transferred across from our domestic livestock.

This would suggest that permafrost and ice sheets include ancient microbes that our species hasn't interacted with for centuries - and which we may therefore have minimal resistance to. Although natural sources of radiation are thought to destroy about half of a bacteria's genome within a million years, there have been various - if disputed - claims of far older bacteria being revived, including those found in salt crystals that are said to be 250 million years old. In this particular case, their location deep underground is said to have minimised cosmic ray mutations and thus ensured their survival. Sounds like one for the Discovery Channel if you ask me, but never say never...

Even if this improbable longevity turns out to be inaccurate, it is known that dormant spore-forming bacteria such those leading to tetanus and botulism could, like anthrax, be revived after decades of containment in permafrost. Fungal spores are likewise known to survive similar interments; with amphibian, bat and snake populations currently declining due to the rapid spread of fungal pathogens, the escape of such material shouldn't be taken lightly.

So can anything be done to prevent these dangers? Other than reversing the increase in global temperatures, I somehow doubt it. Even the location of some of the mass burials during twentieth century reindeer epidemics have been lost, meaning those areas cannot be turned into no-go zones. Anthrax should perhaps be thought of as only one of a suite of biohazards that melting permafrost may be about to inflict on a largely uninformed world. The death of some remote animals and their herders may not earn much public sympathy, but if the revived pathogens spread to the wider ecosystem, there could be far more at stake. Clearly, ignorance is no protection from the microscopic, uncaring dangers now waking up in our warming world.

Amphibian Armageddon and killed-off kauri: the worldwide battle against fighting fungi

I recently wanted to visit the Ark in the Park, an open sanctuary in the Waitakere Ranges west of Auckland that uses constant predator control to protect native plants and animals. However, I was stopped by a sign stating that Te Kawerau a Maki, the Maori of the district, have placed a rāhiu or prohibition on entering the forest. Although not legally binding, the rāhui is intended to stop people walking through the area and spreading infection, serving in place of any notice by the New Zealand Government or Auckland City Council, since the latter two bodies have failed to take action. Perhaps this inactivity is because the infection does not directly affect humans or farming. Instead a fungus-like pathogen is killing the native kauri Agathis australis, one the largest tree species on Earth.

Known to live for over a thousand years and grow to over fifty metres tall, the largest kauri are seen by Maori as the lords of New Zealand's northern forests. Yet since 2009 the microscopic water mould Phytophthora agathidicida has been causing kauri dieback at an ever-increasing rate. Surveys in the Waitakeres show that most of the infected areas are within ten metres of walking paths and therefore the mould is being spread by visitors to the lowland forests who fail to thoroughly clean their shoes with the supplied disinfectant spray. In a truly David versus Goliath battle between the miniscule mould and giant trees, introduced species such as possums and pigs are aiding the former by accidentally spreading the minute spores.

Auckland Council reported last winter that the amount of affected kauri has reached 19 percent, meaning a doubling in scale in only five years. Since there is no cure for infected kauri, some scientists are now predicting the extinction of this magnificent tree in the near future. The combination of the pathogen's microscopic size with its rain-based activation after dormancy means there are currently no methods that can prevent the infection from spreading. In a way, the rāhui may just slow down the inevitable. Considering the immense kauri are home to a unique ecosystem of epiphytes, orchids and associated symbiotic organisms, the future flora and fauna of kauri-free forests may well be markedly different from the Waitakeres as they are today.

I've previously discussed the ubiquity of the unsung fungi and how prominent they are even within totally man-made environments. It seems surprising that New Zealand's authorities, so keen to preserve native birds and reptiles, are failing to take any action to at least buy time for the kauri; perhaps they have already deemed extinction as unavoidable and not worth spending public funds on.

The kauri are far from being the only organisms currently threatened by fungi or their kin. Over the past decade more than thirty snake species in the eastern and mid-western United States have started succumbing to what has been termed Snake Fungal Disease. The culprit is thought to be a soil-based fungus called Ophidiomyces ophiodiicola, with a similar organism now also thought to be affecting snakes in the United Kingdom and mainland Europe. Research suggests that up to ninety percent of infected snakes die from the condition, so clearly if humans and their vehicles play unwitting hosts to the microscopic fungal spores, the future for the world's snake population looks depressing. Although many people might not like snakes, ecosystems without them may see an explosion in the numbers of their prey animals, including rodents; to say the least, this would not bode well for crop farmers!

Perhaps the best-known of the global fungal-caused epidemics is the amphibian-decimating Chytridiomycosis, whose affects were initially recognised twenty years ago but may have started much earlier. As its spores can live in water, the responsible Batrachochytrium fungi are ideally situated to infect about one-third of all frog, toad, newt and salamander species. Again, it is thought that man has inadvertently caused the problem, as the African clawed frog Xenopus laevis is an immune carrier of the fungus and has been exported worldwide since the 1930's.

Another contributor may be climate change, as amphibian-rich forests experience temperature variations that are ideal for the chytrid fungi to proliferate in. As a final nail in the coffin - and as with bees and Colony Collapse Disorder - pesticides may play a key role in the epidemic. Agrochemicals are shown to lower the amphibian immune response and so increase their susceptibility to infection. However, the situation isn't completely hopeless: here in New Zealand, researchers at the University of Otago have used chloramphenicol, an antibiotic eye ointment, to cure infected Archey's frogs (Leiopelma archeyi). This species is already critically endangered even without the chytrid epidemic; hopefully, the cure will prove to be the saviour of other amphibian species too. This would be just as well, considering the dangerous side effects found in other treatments such as antifungal drugs and heat therapy (the latter involving temperature-controlled environments that are lethal to the pathogen).

During the past decade, over five million North American bats have been killed by white-nose syndrome, which is caused by the fungus Pseudogymnoascus destructans. Again, humans have inadvertently spread the pathogen, in this case from Eurasia, where the bat species are immune to it, to North America, where they are most definitely susceptible. The bats are only affected during hibernation, which makes treating them difficult, although brief exposure to ultraviolet light has been shown to kill the fungus. This may prove to be a cure to infected colonies, although how the UV could be administered without disturbing the cave-roosting populations will take some figuring out.

It appears then that a combination of manmade causes (international travel, climate change and chemical pollution) is creating a field day for various tiny fungi or fungus-like organisms, at the expense of numerous species of fauna and flora. The culprits are so small and pervasive that there is a little hope of preventing their spread. Therefore if conventional cures cannot be found, the only hope for the likes of the kauri might be the use of genetic engineering to either give the victim resistance or to kill off the pathogen. This science fiction-sounding technology wouldn't be cheap and its knock-on effects unknown – and potentially disastrous. The former technique would presumably not be any use to the existing populations, only to the germ line cells of the next generation. Whatever happens, our short-sighted approach to the environment is certainly starting to have major repercussions. A world without the magnificent kauri, not to mention many amphibian, reptile and mammal species, would be a much poorer one.

The power of pond scum: are microalgae biofuels a realistic proposition?

I've previously discussed some very humble organisms but they don't get much humbler than microalgae, photosynthetic organisms that generate about half our planet's atmospheric oxygen. Imagine then what potential there might be for their exploitation in a world of genetic manipulation and small-scale engineering? The total number of algal species is unknown, but estimates suggest some hundreds of thousands. To this end, private companies and government projects around the world have spent the past few decades - and a not inconsiderable amount of funding - to generate a replacement for fossil fuels based on these tiny plants.

For anyone with even a microgram's worth of common sense, developing eco-friendly substitutes for oil, coal and gas is a consummation to be devoutly wished for, but behind the hype surrounding microalgae-derived fuel there is a wealth of opposing opinions and potential some shady goings-on. Whilst other projects such as creating ethanol from food crops are continuing, the great hope - and hype -that surrounded algae-based solutions appears to be grinding to a halt.

Various companies were forecasting that 2012 would be the year that the technology achieved commercial viability, but this now appears to be rather over-eager. Therefore it's worth exploring what happens when hope, high-value commerce and cutting-edge technology meet. There are some big names involved in the research too: ExxonMobil, Shell and BP each pumped tens to hundreds of millions of dollars into microalgae fuel projects, only to either make substantial funding cuts or shut them down altogether since 2011.

Manufacturing giants such as General Electric and Boeing have been involved in research for new marine and aircraft fuels, whilst the US Navy undertook tests in 2012 whereby algae-derived fuel was included in a 50:50 blend with conventional fossil fuel for ships and naval aircraft. Even shipping companies have become interested, with one boffin-worthy idea being for large cruise ships to grow and process their own fuel on-board. Carriers including United Airlines, Qantas, KLM and Air New Zealand have invested in these kerosene-replacement technologies, with the first two of these airlines having trialled fuel blends including 40% algae derivative. So what has gone wrong?

The issue appears to be one of scale: after initial success with laboratory-sized testing, the expansion to commercial production has encountered a range of obstacles that will most likely delay widespread implementation for at least another quarter century.

The main problems are these:

1. The algae growing tanks need to be on millions of acres of flat land and there are arguments there just isn't enough such land in convenient locations.
2. The growing process requires lots of water, which means large transportation costs to get the water to the production sites. Although waste water is usable, some estimates suggest there is not enough of this - even in the USA - for optimal production.
3. Nitrogen and phosphorus are required as fertiliser, further reducing commercial viability. Some estimates suggest half the USA's annual phosphorus amount would need to be requisitioned for use in this one sector!
4. Contamination by protozoans and fungi can rapidly destroy a growing pond's entire culture.

In 2012 the US National Academy of Sciences appeared to have confirmed these unfortunate issues. Reporting on the Department of Energy goal to replace 5% of the nation's vehicle fossil fuel consumption with algae-derived biofuel, the Academy stated that this scale of production would make unfeasibly large impacts on water and nutrient usage, as well heavy commitments from other energy sources.

In a bid to maintain solvency, some independent research companies appear to have minimised such issues for as long as possible, finally diversifying when it appeared their funding was about to be curtailed or cut-off. As with nuclear fusion research, commercial production of microalgae fuels hold much promise, but those holding the purse strings aren't as patient as the researchers.

There may be a hint of a silver lining to all this, even if wide scale operations are postponed many decades. The microalgae genus Chlorella - subject of a Scottish biofuel study - is proving to be a practical source of dietary supplements, from vitamins and minerals to Omega-3. It only lacks vitamin B12, but is an astonishing 50-60% protein by weight. As well as human consumption, both livestock and aquaculture feed supplements can be derived from microalgae, although as usual there is a wealth of pseudoscientific nonsense in the marketing, such as the notion that it has an almost magical detox capability. Incidentally, Spirulina, the tablets and powder sold in health food outlets to make into green gloop smoothies, is not microalgae but a B12-rich cyanobacteria, colloquially - and confusingly - known as blue-green algae. Glad that's cleared that one up!

If anything, the research into microalgae-derived biofuels is a good example of how new technology and commercial enterprise uneasily co-exist; each needs the other, but gaining a workable compromise is perhaps just a tricky as the research itself. As for Government-funded projects towards a better future for all, I'll leave you to decide where the interests of our current leaders lie...

Moulds, mildew and mushrooms: living cheek by jowl with fungi

There is a form of life that probably exists in every house, office and workplace on the planet (operating theatres and clinical laboratories largely excepted) that is so ubiquitous that it goes chiefly unnoticed. The organisms are stationary yet spread rapidly, are composed of numerous species - some of which include common foodstuffs - and are neither animal nor plant. In other words they belong to the third great kingdom of macroscopic life: fungi. But what are these poor relations of the other two groups, seen as both friend and foe?

Having moved last year from a one hundred and thirty year old, centrally-heated and double-glazed terrace house in the UK to a single-glazed, largely unheated detached house less than a quarter that age in New Zealand, I've been able to conduct a comparative domestic mycology experiment. Without sounding  too much like a mould-and-spores collector out of a P.G. Wodehouse story, the subject has proved interesting and reasonably conclusive: a family of four moving to an annual climate on average four degrees warmer but with twice the rainfall has not substantially changed the amount or placement of mould in the home; if anything, it has slightly decreased. But then the amount of bathing, laundry and pans on the hob hasn't changed, so perhaps it's not too surprising. The more humid climate has been tempered by having more windows and doors to open, not to mention being able to dry more of the laundry outside. Mind you, one big plus of the move has been not having to use electric dehumidifiers or salt crystal moisture traps, so a few degrees warmth seems to be making a difference after all.

There appears to be a wide range of dubious stories, old wives' tales and assorted urban myths regarding fungi, no doubt being due to the lack of knowledge: after all, if you ask most people about the kingdom they will probably think of edible mushrooms followed by poisonous toadstools. Yet of the postulated 1.5 million species of fungi, only about 70,000 have so far been described. They are fundamentally closer to animals than they are to plants, but as they live off dead organic matter (and some inorganic substances too), thriving in darkness as unlike plants they do not photosynthesise, their reputation is more than a little sinister. The fact they will grow on just about any damp surface, hence the kitchen and bathroom mould populations, reinforces the opinion of them as being unwelcome visitors. So just how bad are they?

Firstly, fungi play a vital role in the nitrogen cycle, supplying nutrients to the roots of vegetation. The familiar fruiting bodies are, as Richard Dawkins describes them, pretty much the tip of iceberg compared to the enormous network of fungal material under the soil. Even so, they are given short shrift in popular natural history and science books: for example, they only warrant five pages in Richard Fortey's Life: An Unauthorised Biography, whilst Bill Bryson's A Short History of Nearly Everything spends much of its four pages on the subject concerned with the lack of knowledge about the number of species. Of my five Stephen Jay Gould volumes totalling over two thousand pages, there are just several, short paragraphs. And at least one of my books even refers to fungi as a simple form of plant life! Yet we rely on fungi for so many of our staple foodstuffs; it's just that they are so well hidden we don't consider them if they're not labelled as mushrooms.  But if you eat leavened bread, yoghurt, cheese or soy sauce, or drink beer or wine, fungi such as yeast will have been involved somewhere along the line. On another tack, fungi are party to yet another knife in the coffin of human uniqueness, since both ants and termites cultivate fungi: so much for Man the Farmer.

As this point I could start listing their uses in health cures, from traditional Chinese medicine to Penicillin, but my intention has been to look at fungi in the home. Anyone who has seen the fantastic BBC television series Planet Earth might recall the parasitical attack of the genus Cordyceps upon insects, but our much larger species is far from immune to attack. Minor ailments include Athlete's Foot and Ringworm whilst more serious conditions such as Candidemia, arising from the common Candida yeast, can be life- threatening . The spores are so small that there is no way to prevent them entering buildings, with commonly found species including Cladosporium, Aspergillus, and our old friend Penicillium.

Once they have a presence, moulds and mildew are almost impossible to eradicate. They are extremely resilient, with the poison in Amanita species such as the death cap failing to be destroyed by heat. An increasingly well-known example is the toxin of the cereal-infecting ergot, capable of surviving the bread-making process, even the baking. Indeed, ergot has seemingly become a major star of the fungi world, being used in pharmaceuticals at the same time as being nominated the culprit behind many an historic riddle, from the Salem witch trials to the abandonment of the Marie Celeste. Again, lack of knowledge of much of the fungal world means just about anything can be claimed with only dubious evidence to support it.

A rogue's gallery of household fungi
Although we are vulnerable to many forms of fungus, an at least equally wide range attack our buildings. Whether the material is plaster, timber or fabrics, moulds and mildew can rapidly spread across most surfaces containing even a hint of dampness, often smelt before they are seen. At the very least, occupants of a heavily infested property can suffer allergies, sinus problems and breathing problems. As an asthmatic I should perhaps be more concerned, but other than keeping windows and doors open as much as possible there doesn't seem much that can be done to counter these diminutive foes.  As it is, vinegar is a favourite weapon, particularly on shower curtains and the children's plastic bath toys. Even so, constant vigilance is the watchword, as can be seen by the assorted examples from around the house above. For any mycophobes wondering how large fungi can get indoors, I once worked on a feature film shot in a dilapidated Edwardian hotel in central London about to be demolished which had fungal growths on the top floor (saturated with damp thanks to holes in the roof) which were the size of dinner plates.

So whether you've played with puffballs or like to dine on truffles, remember there's no escape: fungi are a fundamental element of our homes, our diet, and if we're unlucky, us too. Seemingly humble they may be, but even in our age of advanced technology, there's just no escape...