The carpet is a lush deep kind of green – not too deep a green though. We didn’t order it but I’m not complaining – I like it. Much better than that yellow one we had for a while a few months back.
Next to it is another kind of carpet – very different. The same green background but covered in big blobs of yellow, brown, orange and mixtures of all three. Even some reds. The blobs are large and small, some shaped like the spades suit in a deck of cards, others like a cat’s iris, some with many points, like a star … Didn’t order that carpet either but I like it too. It might not sound that great but you’d have to see it.
There was the wallpaper too, great stretches already unrolled, ready to look at. A blue-white background with puffs of white and, in the foreground, thin black shapes, some of them decorated with those blobs of colours, like those on that carpet. Great contrast with the thin black shapes.
The carpets and wallpaper were just delivered – no order was placed by phone or email. And no request for payment by cash or credit card. Not even an invoice. Totally free! Hard to believe, I know.
Then there was the perfume. No, not in bottles, in the air. I swear! (Yes, I know that rhymes but I didn’t plan it). It was heady but not in the way that rose is, or honeysuckle, or privet flower. Those aromas make you kind of want to sit down and drowse …. or even lie down and go to sleep. Then you remember the story of the artist who died inhaling in his sleep the aroma of flowers he had in a vase to paint – and you don’t linger too long. Did that really happen? Not sure – best not take the chance. Didn’t take a chance on the dandelion flowers when you were a kid either. Waking up in a wet bed is not a pleasant experience at any age but definitely gets worse, even if rarer, as one grows older.
No, this perfume does not make you want to sit or lie down; it makes you want to jump, run (or at least stride purposefully). It is invigorating. That too was delivered free.
All of this – well, most of it – was donated by the trees. Not the green, surely? Not directly, no … but indirectly, yes. The grass grows in the earth which is fed by dead leaves and other material, broken down by insects and fungi and especially recycled through the digestive tracts of worms. May those gardeners who poison worms on their lawns be forever damned!
Before Ireland was denuded of her mixed forests, what a site she must have been!
All this visual, olfactory and mood-enhancing stuff was delivered free to us but there is, you are right to suspect it, a hidden cost. The weather is getting colder and sitting nearly naked on a beach is definitely out, to say nothing of plunging into the freezing water (well, with some lunatic exceptions). Outdoor cafe-sitting is becoming more of an endurance test than a pleasure. There are days coming when lots of good arguments (convincing at the time anyway) will be found against getting up to go about once’s business.
But then there will be glittering jeweled grass, constellation of stars in the pavement, artwork fronds on glass, white star patterns in things floating from the sky, white blankets over everything or at least over the hilltops in the distance, the special joy of a hot soup, a warm fire and blankets (if you have them) ….
And not too long away, sprouting buds pushing through bark and soil, misty green branches, a different perfume, quickening the blood in a different way.
Deire-Fómhair (‘October’, also “End of Autumn’), an exhibition of art by Eoin Mac Lochlainn, was on show this afternoon in the Olivier Cornet Gallery in Great Denmark Street , Dublin and I went along to view it. An installation and 24 paintings are listed.
It is of course the installation that first catches the eye, mainly due to its size, secondarily its colours and viewing it one must, I think, come to the conclusion that the space is too small for it. Artists I suppose must use whatever exhibition spaces are available to them. Standing back as far as one can, the installation still does not reveal its full potential. But photographing in the gaps between the hanging pieces in the first row, one sees tree-trunks, dappled with slanting autumnal light through dying leaves, moss and lichen pattern on trunks and the autumn leaves themselves.
The installation is composed of 64 painted lengths of rice paper and is lit from behind with accompanying recorded bird song which adds to the ambience. In the leaflet accompanying the exhibition, the artist wrote:
This is a traditional paper which originated in ancient China and has been used for centuries for calligraphy, artwork and architecture. It is as white as alabaster, known for its strength and smooth surface, very delicate when wet but said to last for a thousand years – an enchanting medium with which to work.
Around the wall are a number of watercolour paintings, mostly 15×19, some 12×12 and a few 20×20 and one, very different in style and composition, of 45×33. The latter looks older and by another painter and appropriately so, perhaps, since it is an interpretation of a painting by the German Romantic landscape painter Friedrich (1774-1840), “Solitary Tree”, painted probably (according to Google) in 1822, nearly two centuries ago.
The subject seems to be an oak, its upper trunk dead but with leaves on branches spreading further down. It seems to have weathered many storms and perhaps a lightning strike years ago …. but it yet remains, stubbornly alive.
I do not know what motivated either Friedrich or Mac Lochlainn to take this image as their subject but in the leaflet, the latter has written:
Trees are a link between the past, the present and the future. The majestic stature, the long lifespan and the familiarity give them a monument-like quality but they also have a special aura that is difficult to define. Research has shown that within minutes of being surrounded by trees, our blood pressure drops, our heart rate slows and stress levels begin to reduce.
Less calming no doubt are the images of the watercolours which he titles Dóite (‘burned’ but also: ‘wasted, laid bare, destroyed’). The images are bleak, disturbing, of dead tree-trunks in a wasteland. In the accompanying leaflet, the artist notes:
I have been developing a body of work which explores the effects of climate change and in particular, reflects on the significance of trees.
These images could also reflect the negative effects of acid rain, nuclear or chemical contamination or timber monoculture and the exposure of trees thereby to increased likelihood and intensity of infestation by invertebrates and fungi (as for example the latter is attacking pine plantations in the Basque Country).
The watercolour series titled Cosán Coille and Siúlóid Sléibhe are exquisite colour and tone in a way of which I think only watercolours can be. It is surprising then to learn that Mac Lochlainn’s previous work has been in oils and that he found the change exacting:
In recent years, I switched from oils to watercolours in order to have less of an impact on the environment.
The switch has been both challenging and rewarding – challenging to master the idiosyncrasies of the medium but very rewarding in discovering new possibilities and avenues of enquiry for my practice.
The smaller size of the paintings restrains one from being pulled into them, the way a larger painting might do but that does not prevent them from being beautiful, sometimes in an almost painful way.
Trees have been called “the lungs of the world” and were considered of great importance to the Celts; the Gaels peppered our place-names with references to them: abhall (apple), áirn (sloe, fruit of the blackthorn), beith (birch), caorthainn (rowan), coll (hazel), cuileann(holly), dair (oak), draighneán (blackthorn), fearnóg (alder), fuinnseog (ash), giúis(fir, pine, deal), iúr (yew), sail or saileach (willow),sceach (whitethorn, normally).1 They appear also in many of our folk-songs.
Prices of paintings range from 380 Euro to 1,200 and the gallery offers a service of payment by installment. The artist, Eoin Ó Lochlainn, who happens to be closely related to Patrick Pearse, has had numerous exhibitions in each year going back to 2013 and has won a number of awards. Collections of his artwork are held inAIB, Bank of Ireland, OPW, Revenue Commissioners, AXA Insurance, Foras na Gaeilge, Gael Linn, the Boyle Civic Collection, Wesley College, University of Limerick, Donegal County, Cló Ceardlann na gCnoc.
People visit the Basque Country for different reasons — among the touristic reasons are cuisine, folk culture and beach-type tourism including surfing. For some there may be business reasons and possibly on the other end of the spectrum from them there is the political aspect – interest in and solidarity with their struggle for independence and to a lesser extent perhaps, socialism. Eco-tourism and archaeological interest are probably not high on the list for most people but I’d suggest it would be worthwhile to include sites dealing with such aspects in any itinerary.
Many Basques would tell you that their country has a long way to go in environmentally-friendly practices – or at least in those less harmful to the environment; if true, it serves to illustrate just how far behind the desirable are the practices common in Ireland. Everywhere in Basque village or town, one sees the recycling containers in their five different colours for paper, plastic, metal, glass and organic waste. One frequent complaint is about timber-production forestation practices and though much of the Basque country is green with trees, many of those trees are conifersor, even worse, Basques will say, eucalypts in mono-cultural acres. The latter are indeed widespread and are said to suck the moisture out of the soil so that after they are felled, little else can grow there.
Environmentally-friendly timber production is less intensive and more diverse in species, less harmful to biodiversity of plant and animal life and more protective of the soil from erosion, flooding and desiccation. But to business — and therefore mainstream political interests — it is slower in turnover of profit. The perils of this concentration on early profit gain have been underlined this year with the infestation of the main crop pines, the “Monterey pine” (Pinus radiata) by the ‘Mycosphaerella dearnessii’ fungi and ‘Mycosphaerella pini’, said to have originated in Central America, which turns the foliage (needles) brown, eventually leading to the destruction of the tree.
That all said, at grassroots (forgive the unintended pun) and often municipal level, there is great interest and support for biodiversity in the Basque Country and discussion around the subject is much more socially widespread than one would find in Ireland or in most of Britain (though perhaps not in some other parts of Europe). There are many national parks and reserves of great beauty and even city Basques tend to have a culture of collecting edible fungi in the woods in the autumn and of hill-walking or mountain-climbing at various times of the year. And small farms can be found dotted throughout the countryside.
Education about the environment for adults, children and even tourists is taken seriously and, apart from schools, centres promoting environmental care can be found in many areas. One such site of interest is the bio-diversity and heritage centre of Madariaga, the Ekoetxea, in the Axpe de Busturia area between the towns of Bermeo and Gernika These are interesting towns in themselves of the coast of Bizkaia (Biscay) province and Gernika was of course made famous by its bombing by the Nazi Luftwaffe, in the service of the fascist generals (Franco et al) in 1937, during what probably most people call the the Spanish Civil War and others, the Iberian Anti-Fascist War. Bus and train services connects both towns and pass through Busturia, both services having a stop or station in Axpe. The bus and train services run at mostly half-hourly intervals, the train all the way to Bilbao, on a single track for much of the line, up and down trains alternating.
I dropped in to a charming tavern in Axpe named after the Basque flower, Eguzkilore: literally “Sun Flower”. This is not the “sunflower” which Van Gogh famously painted, so named because it turns to follow the sun through its journey across the sky; the Basque flower (Carlina acaulis)is a member of the thistle family and is thought to resemble an idealised image of the sun. Dried specimens are often found hanging over the front door of Basque houses as a good-luck symbol, quite probably a remnant of pagan sun-worship (like the Irish “St. Bridget’s Cross” and indeed the traditional Basque symbol of the lauburru is very like that Irish symbol too and interestingly, the Basque tradition related to me was that it was borrowed from the Iberian Celts).
The Eguzkilore tavern is owned by a friendly young couple, a Catalan woman and Basque man: he of course speaks Euskera and Castillian (Spanish) fluently, whereas she is fluent in Catalan, Castillian and English, speaks Euskera well and smatterings of other languages. Although I know from experience that their cuisine is excellent, I ordered only a simple kafe esnea there and after finishing it and a chat, set off up the road to the Madariaga Ekoetxea (“eco-house”), an easy walk of perhaps fifteen minutes. Turning left at the roundabout at the crest of the hill the centre was easily visible by the clock-bell tower and the taller viewing tower.
This latter was a defensive construction quite similar to the keeps constructed in Britain and Ireland by the Norman invaders, livestock quartered below and people living on floors above; one of the staff told me that it had been inhabited until the 1930s. Now the floors have been ripped out except for the top one, accessible by a short journey in a lift and once there one can view around something like 160 degrees: steep hills close by beyond the road, land sloping away towards Gernika and distant mountains on another side, beach of the estuary and some marshlands on another.
The Tower was in fact the last part of the centre which I experienced. It was a showery Sunday in mid-October and the centre was fairly quiet, less that ten vehicles in the car park and nobody but a receptionist immediately available upon entering the building. I used my limited Euskera in addressing her, which is my practice in the Basque Country, and which is usually – but not always – appreciated. The native language has become “politicised” here (as some say it has also in the case of Irish in Ireland), which is another way of saying that it was banned under the Franco dictatorship, that people of a Spanish unionist turn of mind often resent it and native speakers, learners and independentists want to encourage its spread and use in everyday life. Of course in a cultural type of centre in the Basque Country I would not expect any negative response and I was answered politely in Euskera with a quick conversion to Castillian when my limited store of Euskera ran out.
WATER AND BIODIVERSITY
I had seen a small charge advertised outside but there was none on that day or perhaps that time of year to see two standard exhibitions, one on water and the other on biodiversity. The one on water informs visitors that water is a circulatory system: 1) most of it falls from the air in rain or humidity, some of it on to land and some on to lakes or on to the sea; 2) some of that which falls on land is taken up by soil and vegetation and excess runs off into streams, rivers and lakes; 3) some also soaks through permeable or semi-permeable strata of soil and rock and forms underwater reservoirs and lakes. 4) The excess runs out in underground rivers and streams, emerging eventually to empty into seas and lakes, where 5) the sun heats up the top layers again, creating clouds, many of which precipitate on to land, renewing the circle.
The diagrams, photos and videos demonstrated this process well and attractively and there were samples of varieties of sandstone and limestone to examine at close quarters. For me, the photos of underground caves formed by the water wearing away the limestone and the various and sometimes fantastic formations caused by chemical-rich water dripping for millenia were the most impressive along with the few examples of invertebrates adapted to life without light and mammals using natural caves were the most interesting, while others might have found the supplying of water to the public of greater interest (and certainly this is an important issue in many countries and not least so in Ireland).
The section dedicated to bio-diversity is divided into different parts, including a room with video screens showing different types of humans (ethnic, gender, possibly sexuality, culture, age) and others dealing with plant, fungi and animal life. Passing through a type of broad corridor with explanations of what is a definition of biodiversity in many languages, one enters a brightly-lit room seemingly constructed entirely of panels, each one of an animal: birds, mammals, fish, reptiles, insects and other invertebrates. Not only the walls but floor and ceiling appear constructed of the panels, a vibrant bright room somewhat evoking the effect of stained glass with light shining through, a church celebrating the diversity of animal life, perhaps.
Walking onwards, one finds a hall filled with large cubes, standing haphazardly upon one another, each carrying the image of an animal or plant. The names of the species are given in Euskera, Castillian and Latin. I find myself at times wishing to see the names in English and then chiding myself for the unreasonableness of this wish. There are images of plants to be seen too, some of plants which we are informed are native to the country and one found only there.
ATTRACTIONS IN THE WIDER AREA
A slim informational folded leaflet is available in a number of languages, one version being in English and French, not only about this centre but about a network of them managed by the “Basque Government” (i.e the Government of three of the southern Basque provinces, Biskaia, Gipuzkoa and Alava). These are visited every year by 100,000 people, the booklet informs us, 25,000 of which are schoolchildren; the ekoetxea which I visited receives 2,000 schoolchildren out of a total of 45,000 visitors annually.
Another, more substantial booklet available in English which shows signs of translation probably from Castillian gives more information on the Urdaibai Biosphere Reserve, the wider area in which the Madariaga Ekoetxea is located. This booklet advertises nature trails for hiking or biking, restaurants for Basque cuisine, a cave occupied by prehistoric humans, the Gernika Tree and General Assembly building and museum, markets and folk festivals, cider and wine-houses, painted forest, hermitages, bird-watching and sea activities including surfing and whale and dolphin-watching. Strangely (or not), in its caption about Gernika, it has nothing to say about the bombing of the town in 1937 nor, in its references to human habitation and culture of the wider area, nothing either to say about the Spanish Civil (i.e Anti-Fascist) war or about the occupation of the area by the fascist troops and the repression that followed, nor about the suppression of their language under Franco.
An information panel tells visitors that there are 3,335 different mammal, bird, fish, reptile, amphibian, fungi and plant species etc. in the the Urdaibai reserve and that 85 are in danger of extinction or are of special interest. Some panels showing examples of these would be welcome as would more about the wildlife native to the area (like what species are the owls one can hear hooting at intervals through the night from the forested hill above Axpe, for example).
You sniff the scent of blooms in the air and it pleases you. But that’snot what it’s for – the scent was not manufactured to please you. Scents derived from plants are used by humans to add to their sexual allure and plants also have a sexual function in producing them — but it is not humans the plants are trying to attract.
The scents are there to attract pollinators, insects, mammals or birds that will go to them to collect pollen and/ or nectar, in the course of which they will spread pollen from plant to plant and bring about fertilisation.
There are huge numbers of different chemicals producing scents and combinations of scents and, as the plants have developed them, their pollinators have also developed the ability to distinguish between them and to home in on the appropriate ones. It is likely that inside the pollinators some kind of receptor is created which is keyed into the specific scent, in much the same way as sexual pheromones are keyed into receptors inside so many species, including humans.
These pollinators then, quite unintentionally, dive into another bloom somewhere and like some kind of romantic couriers, deliver the pollen to the eager recipient. But unromantic really, to receive fertilisation from an unknown lover, unseen and barely felt. Yet it works, as around 400,000 flowering plants testify (though not all flowers use scent — colour and form suffice for some). And it will continue to work, as long as there are pollinators around (which is turning out to be a problem with large-scale deaths of bees, by far the most active of pollinators). But the animal kingdom? With some exceptions, its members need the presence of both sexual actors or more and stimuli to engage in sexual activity that will lead to procreation: temperature, light, foods, natural odours, shape, touch, erotic imagining, poetry, music, clothing, colour …. and yes, applied plant and artificial fragrances.
The scent of flowers is composed of a variety of VOCs (volatile organic compounds), most plant scents being composed of many compounds and some of up to several hundred. Collecting, isolating and analysing these compounds present great challenges to scientists but even small insects know what they mean, like an olfactory equivalent of a neon sign: NECTAR AND POLLEN HERE!.
Some plants emit scent throughout daylight and some at specific times of day only. And some not until after the sun has set. At night of course the plants do not have much competition but which pollinators will be active at night? Moths are the big group here but there are others, such as some bats.
There’s a night-scented shrub near my home that made me want to look into this subject and write about it a little. This time of year at night it is producing a strong sweet scent (with, to my nose, just a touch of urine smell in there too). You won’t find moths flying around at this time of year in Ireland and it’s not attracting bats so I guessed that it’s a foreigner and, where it comes from, that this time of year would be perfect. The shrub in question is the “Sweet Box” (Sarcoccoca confusa) and I was not surprised to find that its “native heath” is in eastern and southeastern Asia and the Himalayas.
People like the scent but it’s kind of sad when one thinks more about it, what it’s trying to do, like posting a message of sexual availability and procreation-wish on to a dating page and …. no-one replies.
Blooms and other parts of plants also produce scents which do not appear to have any role in attracting pollinators and scientists believe that these are defensive scents to ward off herbivores. In this case the olfactory sign is saying: “HORRIBLE TASTE! REMEMBER?” Not only that but plants can increase the production of such scents as parts of them are being eaten, to the extent that their attacker feels obliged to desist1. And some scientists also speculate that scents for pollinators developed first as scents to discourage herbivores.
Given that some animal appropriators of plant products have learned to home in on the repellent scents of some plants this seems quite likely. Imagine a plant exuding a smell to ward off a herbivore and imagine an insect learning that where that particular smell is to be found, so is food such as nectar or pollen. The sign now says: HORRIBLE-TASTING TO HERBIVORES AND PARASITES but is accompanied by another sign that declares: FREE DELICIOUS FOOD FOR OTHERS! And the plants that most reach and “please” the accidental pollinators will naturally be more successful, be visited more often and spread their genes wider. Unless yet other animals learn to follow that scent in order to consume the plant, or lay their eggs on it for the larvae to feed on the plant. Cabbages and carrots for example, both of which have an odour we can identify, have eggs laid on them respectively by the cabbage butterfly and the carrot fly, which are then fed upon by the larvae as they hatch. And the butterfly and carrot fly find the plants by smell.
It is a difficult balance, to attract pollinators and yet repel herbivores and parasites and no doubt the balance is constantly being adjusted through the evolutionary processes of plants, herbivores, pollinators and parasites, in a kind of dance of love and death.
Those volatile compounds to be found in the scents of flowers almost certainly also make them difficult to keep fresh. The cut flowers business is a billion-euro one and growers have now produced blooms that last longer after cutting than they used to – sometimes for weeks. But scent?One of the most delightful scents to the human nose is that of the rose, about which songs have been sung and poems composed. Go into a florist, go to a bunch of roses and try and smell them — the chances are you won’t be able to.
Shakespeare’s Juliet, who said that “a rose by any other name would smell as sweet”2 might say today that “A rose without a scent is but half a rose”. When you do find a rose or another flower that is sweetly scented, breathe deep and enjoy the scent … but remember it’s not made for you. It’s for another flower, through the agency of a courier, a messenger.
They are all around us; they live but they are not animals. Nor are they micro-organisms – we see them clearly all in many places. They can grow on organic and none-organic surfaces. We might think they are plants – algae, moss or fungus but they are none of those — they are lichens. There are about 20,000 known species1 and they cover an estimated 6% of the Earth’s surface, able to exist in environments as different as beneath Artic snow, on salt spray-showered seashores and windswept mountain rocks and in tropical rainforest. An estimated 6% of the Earth’s land surface is covered by lichen species.2 Some are long-lived and include the longest-living things on Earth. There are species that require nothing to cling to while others can live inside rock, in the spaces between grains.3In Ireland, 1,134 separate species of lichen have been recognised, according to the National Biodiversity Data Centre – i.e over 5% of Earth’s estimated total species right here on this little island.4
When we look at some growing on tree bark or rock, we are tempted to think of them as fungus, algae or even moss. Mosses are ancient enough life-forms and are plants, which algae are too and almost certainly much older. Fungi used to be considered plants but are so no longer and in their structure and digestion and also genes, are more akin and more closely related to animals. This will not be good news to vegetarians or vegans but the evidence is difficult to deny.5 Indeed there are some feoilséantóirí (word in Irish for a vegetarian and more apt in the context of this sentence) who already dislike eating many fungi because the texture reminds them of meat.
But lichens are neitherfungi nor plants.
So if lichens are not plant or fungus, what are they? Another kind of life-form? Well yes … and no. They are a combination of both, fungus and plant. At some point in the evolution of life on earth, logically after plants and after fungi had evolved, somehow some species of fungi combined with some species of alga and/or cyanobacteria6 and produced a symbiont or biont: lichen. Scientists maintain that the 20,000 estimated species did not evolve from one common ancestor but that different species appeared separately at different times during the history of the Earth.
Plants draw their nutrients from sun and elements in the soil (or in some cases, in the water). Fungi, like animals, cannot get their nutrients straight from sun or soil and need to break down their alimentation materials, whether flesh or plant, in order to feed on them. In doing so, fungi are important decomposing agents – in fact, the principal ones.
Vascular plants need roots not just to cling to soil but even more importantly, to draw up water and nutrients but algae don’t; when they have any kind of roots, it is to cling to a surface and that is exactly what the lichen needs too. Fungi extend and feed through root-like growths usually under the surface of what they are feeding upon, extending from the tips; they are not roots, however and break off easily.What we see of fungi is usually the spore-bearing parts above the surface, often much the smaller part of the organism.
Plants seem to grow above ground also by elongating their tips but in fact are extending from further back, adding cells to cells to lengthen the body. All plants need a constant supply of water (cacti and succulents store water but still need to draw on the supply to live). Fungi need damp conditions. But when combined into lichens, the new species can live without water for a considerable time. So, a marriage, as they say, “made in Heaven” … or perhaps in a Hell, an environment of very dry and hot conditions alternating with the very wet and cold , where the newly-wedded ancient algae and fungi set out to build their homes.
Some lichens contain not only algae combined with a fungus but also a cyanobacterium; this partner is capable of fixing nitrogen extracted from the air and is a valuable addition to the menage-a-trois.
It has been remarked by some that the marriage of plant and fungus is not an equal one, is not true symbiosis, since the fungal partner or symbiote benefits more than does the algal. The algal symbiote produces sugar through photosynthesis and the fungus only chitin, or ‘hard‘ structure, it is argued. However, if both partners (or three) are content with the arrangement, is that not a happy marriage? More seriously, the fungal partner may contribute other factors to the symbiosis of which scientists are only just becoming aware – for example, chemicals to repel organisms attempting to graze on them and protection from the sun.
And scientists do not treat them equally either, since the species of lichen is always determined and named by them according to the species of fungus, not of the alga or bacterium.
COLOURS IN THE RAIN
So, if the claim is that we see them all around us, where are they? They may be seen on slate roof-tops, in patches of roughly circular white (not to be confused with pigeon or seagull excrement, which may also be in evidence). Yellow or orange patches are typically seen on stone, as is a black or dark brown one by the seaside. A bright yellow-green one may be seen on fallen twigs or on tree-bark, as may also a tufted-form green one growing on rock or tree.
The colours tend to be particularly vivid during or soon after rain when the cortex becomes translucent and, if there were no other reason to be grateful for the precipitation levels usual in Ireland, that would be reason enough, perhaps, should we take the time to admire the little things of beauty. Of course there are other reasons and as a Basque once said to me about the green of his native country and could perhaps even more accurately said about colour associated with the “Emerald Isle” — “It’s not green because we paint it.”
Some of the bright colours in lichens, produced by the fungus, are thought to be of use in protection from the rays of the sun and become more vivid after rain due to rapid absorption of water by the chlorophyl-holding part of the symbiont (or biont).
PIONEERS AND SURVIVORS
Lichens are considered “pioneer organisms” by botanists and geologists, i.e organisms that set out to colonise new territories. These maybe new territories in the sense that a geological change has exposed them to air, e.g from the seabed or from under ice, or from inside the earth by volcanic action or by tectonic plate collision.
Pioneer organisms need to be tough and adaptable and they often create footholds for other species, not quite so tough or adaptable, to follow after. However, given that logic dictates that algae and fungi existed before some of them combined to form lichens, the latter could not have been among the earliest colonisers of the Earth’s crust. On Earth then, they are later pioneers of newly-created inhospitable terrain.
May they be used to help create habitable environments elsewhere? It’s perhaps worth quoting these two paragraphs from Wikipedia in their entirety:
In tests, lichen survived and showed remarkable results on the adaptation capacity of photosynthetic activity with the simulation time of 34 days under Martian conditions in the Mars Simulation Laboratory (MSL) maintained by the German Aerospace Center (DLR).
The European Space Agency has discovered that lichens can survive unprotected in space. In an experiment led by Leopoldo Sancho from the Complutense University of Madrid, two species of lichen — Rhizocarpon geographicum7 and Xanthoria elegans — were sealed in a capsule and launched on a Russian Soyuz rocket 31 May 2005. Once in orbit, the capsules were opened and the lichens were directly exposed to the vacuum of space with its widely fluctuating temperatures and cosmic radiation. After 15 days, the lichens were brought back to earth and were found to be in full health with no discernible damage from their time in orbit.
In some areas, soil lichens help to bind the sand-crust or soil-crust together but lichens have also been shown to chemically attack stone, thereby helping to create soil. Lichens can also help create little environments where soil may be retained and seeds of plants germinate. However, like all species, lichens are out to help themselves and some produce chemicals to restrict the march of mosses (another pioneer species but more water-reliant), with which lichens would have to compete in many areas).
When growing on tree bark, lichens do not parasitise on the tree nor harm it in any way, merely using it as a secure base. Older trees are often covered with lichen and dead trees or branches more so, associating in some people’s minds the ill-health in a tree with the growth of lichen upon it. Circumstantial evidence may suggest the guilt of the lichen but it is completely a case of coincidence: lichen is slow-growing and the older the tree, the more time lichen has had to grow and extend upon it; the tree dies because it grows old.
The lichen will survive the dead tree for a period but it is not the killer. Now come decomposers: insects, snails, slugs and especially, distant relatives of the lichens: fungi. Without concern for their relatives, the fungi, along with the other decomposers, will reduce the tree to soil ingredients and thereby deprive the lichens of their base but, in time, providing more soil for more trees to grow and for new generation of lichens to attach themselves to the bark.
The fungus is not too discriminating and a particular species may combine with different algae species; the resultant lichens may appear to be different species but (since 2014) will be classified as the same lichen species, i.e containing the samespecies of fungus.8
The alga can also exist independently in nature but the fungi cannot. Two species in two genera of green algae are found in over 35% of all lichens, but can only rarely be found living on their own outside of a lichen.9
Sex and Reproduction
It is only the fungal part of the symbiote that reproduces sexually. When doing so, it produces spores (as do ferns and mosses) which must find a compatible alga in order to produce a new lichen, a symbiote of the fungus of the parent fungus and a new alga.
Some lichens reproduce or extend asexually, advancing across a surface and merging with another of the same species.
Uses of lichens:
When we discuss “the use” of some thing we generally mean its use for humans; lichens no doubt have many uses for other organisms, whether as food for reindeer during non-growing seasons or as micro-environments for tiny creatures. But for humans, the uses are mostly in the areas of
geological age indicators
Dyes and Pigments:
Dyes were made from the orange Xanthoria Parietina and the grey-green branched Parmelia Saxitillis to dye wools used in traditional tweed (Harris) weaving in the Scottish Highlands10and I myself have had the second of the two pointed out to me by an Aran Islander woman as the source for the rarely-used green wool knitted into a geansaí (pullover or jumper). Material for other natural dyes exist for example in Ireland but the issues are how easily they are obtained, how true they dye and how long they remain the desired colour and shade.
“There are reports dating almost 2000 years old of lichens being used to make purple and red dyes. Of great historical and commercial significance are lichens belonging to the family Roccellaceae, commonly called “orchella weed” or “orchil”. Orcein and other lichen dyes have largely been replaced by synthetic versions.”11
We know that red and purple dyes were much sought after and in some medieval civilisations the wearing of those colours was restricted to certain social classes and even to one individual (e.g the purple for the Emperor). Once Europeans had gained familiarity with indigenous civilisations of Central and South America, the red dye obtained from the parasitic cochineal insect Dactylopius coccusbecame an important export product to Europe until the late 19th Century, when synthetic pigments and dyes were invented. Despite this development, traditional hand-made textile producers, for example in regions of Mexico, continued to use cochineal dyeing. However, health concerns associated with some or all of those synthetic colourings in food have once again created a demand for cochineal and cultivation of the insect is once again economically viable, with Peru being currently the main exporter.12
Drugs and Medicine:
There is reason to believe that metabolites produced by lichens may have antibiotic effects and usnic acid, the most commonly-studied metabolite produced by lichens, is being investigated as a possible bactericide, in particular against Staphylococcus and E.coli.13
Lichens were also used in European traditional medicine, in particular based on the theory that plants that resembled human organs would be efficacious in treatment of illness of those organs. Some American Indigenous people also used them in traditional medicine treatment.
Lichens as Indicators of Geological Age and of Pollution Levels:
The science of lichenometry is a relatively new one in which measuring the type and size of lichen is used to indicate the age of exposed rock. It takes the known slow growth-rate of different lichens to arrive at an estimate of how long the rock in question has been exposed. This can be used on rock formations, landslides, stone buildings and statuary.
The tolerance (or lack of tolerance) of different species of lichen to certain types of air and rain pollutant can be used as bio-indicators. In general the “frond” or “bushy” types are less resistant to some air pollutants and the flat or “crusty” types more so. Lichens take their water from the surfaces to which they are attached and from the air and are therefore quickly affected by the water quality in rain and air.
Readers may find it worthwhile to take some time to examine the lichens growing around us, to think about their unusual ‘domestic arrangements’ and their pioneering habits. Or to inventory them as indicators of the level and content of pollution in a specific area.
And in particular, to put on rainproof or resistant clothing and to view lichens during rainfall or at least very soon afterwards.