ODE TO GREEN
Stifle envy, set aside jealousy and rise for a moment above greed. For right now, when we need it so badly, green most definitely means grow. By Ashley Hay.
It’s a colour fundamental to our natural world, from sweeping vistas to the environment in miniature. And, says ASHLEY HAY, it’s needed now more than ever.
AFTER A SUMMER of heat, drought and devastating fires, it’s a poignant time to think about green – the colour most often associated with life, with nature, with renewal. Green stands for jealousy – Othello’s “green-eyed monster” – and for envy and for greed. But green for growth, and green for go now, too. This hasn’t always been the case. The first standard lights chosen by railways in the 1830s used red for stop – picking up on its long associations with danger – but white for go. Green, originally, was chosen to signify caution. Problems occurred if the coloured lenses fell out of any of the warning lights, leaving the white light source exposed… and giving an apparent signal to proceed. Problems occurred, too, if bright white signals were mistaken for stars – or stars themselves were mistaken for those early “go” lights. And so the system was recast.
THROUGH THE
WINDOW above my desk, I can see dozens of greens. There are seven or eight different tints on the closest stem alone: different colours for different stages of growth. So many tones scooped in by this one word, the vastness of hues and tints and tones contained in it.
Our eyes can discern more greens and more reds than any other chromas
– we “prioritise” distinction of these colours. One explanation for this is that it’s an evolutionary constraint: the red and the green cones in our eyes “largely overlap”, perhaps because the gene that codes for our green receptor and the gene that codes for red were almost identical and haven’t yet evolved enough to differentiate.
Another is the evolutionary advantage of being able to gauge the difference in ripening fruit. Humans are trichromatics (organisms with three separate channels for distinguishing colour) who eat a lot of fruit (like other New World monkeys), which makes the importance of choosing which fruit to eat a “plausible selection pressure”.
“How many colours are there in a field of grass to the crawling baby unaware of green?” asks the American experimental filmmaker Stan Brakhage. As they crawl through smaragd, through prasine, through chrysoprase, through viridescence – and that’s only imagining their journey in lesserused English. The Himba, an indigenous tribe of around 50,000 in northern Namibia, have the colour system most distinct from any Euro-american systems: it’s divided into language for dark, very light, dry desert colours, and then vivid green and blue, between which last two they make no distinction – they register
a circle with 11 green squares and one blue as a circle with 12 buru squares.
CHLOROPHYLL, one of the fundamental ingredients for photosynthesis, is what gives a plant its green. This nourishing process converts light into sustenance for vegetation – it’s one of the fundamental mechanisms of life, of growth.
As early as 1704, Isaac Newton suspected a link between light and growth in his Optiks, suggesting that “gross Bodies and light [were] convertible into one another”. He meant this in a more alchemical than biological sense: that magical thinking that would give us the power to transform one material into another. But work by researchers in the subsequent years of the 18th century – including Joseph Priestley and Antoine Lavoisier – led to Jean Senebier’s 1782 deduction that green plants “breathe in” carbon dioxide from the air and “breathe out” oxygen, all through their interactions with sunlight.
The “basic equation” of photosynthesis, a process by which “a green plant illuminated by sunlight takes in carbon dioxide and water and converts them into organic material and oxygen”, was confirmed by work published by Nicolas de Saussure in 1804.
An alchemy all of its own.
Perhaps one of the most beautifully symbiotic uses of chlorophyll comes from the small green sea slug Elysia chlorotica – a marine opisthobranch gastropod known not only “for kidnapping the photosynthesising organelles and some genes from algae” but for retaining these in working order for the slug’s year-long lifespan.
In 2010, this slug was found to have “acquired enough stolen goods” to generate the complete “plant chemical-machine pathway work inside an animal body”, according to researchers at the University of South Florida in Tampa. It raised the possibility, in the words of one zoologist, of “branch tips touching” in the tree of life. And in a poetic twist, the slug itself resembles a delicate green leaf – as if it is embodying the plants whose mechanisms it now mimics.
It was also found that “once a young slug has slurped its first chloroplast meal from one of its few favoured species of Vaucheria algae, the slug does not have to eat again for the rest of its life. All it has to do is sunbathe”.
By 2018, populations of this slug in the wild had shrunk to the point where they were becoming “too rare to research”.
But green pigments are surprisingly rare in the animal world. Even among birds, only a handful sport features of a true green – most green feathers arise through a combination of blue structural colouration and yellow carotenoids. One exception is turacoverdin, a unique copper pigment that generates bright green plumage in several birds from the Musophagidae family, most notably the turaco. The birds accumulate copper through the fruits, flowers, buds and other plants of their diet. It’s not known if turacos have especially copper-rich diets, or are better at extracting copper from their foods.
Some of the greens outside my window come from casuarina, dianella, dietes, Alpinia caerulea. Since the rupture of this continent’s landscape after 1788, many of these plants have worn names that speak more of the northern hemisphere – sheoaks, lillies, ginger, iris – the linguistic component of what the historian, geographer and biologist Alfred W Crosby has described as the attempted creation here of a “neo-europe”. The “foreign aspects of Australia’s nature and ecology caused many Europeans to react by imposing their own plants and animals in order to ‘improve’ the land,” writes Lucinda
Janson in her account of imperial settlement and expansion in early colonial NSW.
Theirs was often a “confused and defensive reaction to an ecology and a way of living in a land very different from their own”. To homesick
British colonials such as Barron Field, this country’s colour
“How many colours are there in a field of grass to the crawling baby unaware of green?”
could be dismissed as “one cold olive”, monotonous and harsh.
It’s hard to think of anything less monotonous than the greens in my front yard, particularly after the relief of much needed rain – including 130 millimetres on a single day. The plants perk up; enriched. It’s an almost instantaneous reaction in this one tiny plot of a continent’s space. It makes me wonder about the different greens of plants that might be absent – or present – across more than 18 million hectares of the rest of the continent that’s burned out in recent weeks. Photographs document tiny bursts of colour in the blackened space – always so sudden; always so relieving – while scientists begin to estimate the number of extinctions that may be under way.
THREE QUARTERS OF AUSTRALIA’S threatened species are plants, often with restricted range; a single fire could spell the end for species’ entire populations.
After previous fire seasons, the first sprouts of new growth – clusters of grass, new shoots on trees – have shimmered like dot points of hope. In the first weeks of 2020, scientists write that with the frequency and ferocity of these last fires, entire ecosystems can be pushed “beyond their limits of resilience”. They write, instead, of ecosystem collapse.
In the 1990s, the Danish-icelandic artist Olafur Eliasson discovered he could dye rivers a safe but startling and incandescent green using uranin, the disodium salt form of fluorescein. He’s since performed this artistic intervention a half-dozen times, in rivers in cities throughout Norway, Iceland, Germany and the US – always unannounced. In Los Angeles, “nobody cared, nobody stopped, nobody looked”, he has reported, while in other cities people reacted “with fear and distress”.
All these cataclysmic transformations, these great changes we can wreak. It’s a time the world’s greens should feel so much more rare and precious, whatever names they go by, as chlorophyll continues to transform sunlight into life.
Photographs document bursts of colour in this or that blackened space while scientists begin to estimate the number of extinctions that may be underway.