The nearly magical properties of fig trees

In Cherrapunji, India, locals mold the roots of the fig species Ficus elastica tree into living bridges. Credit: 2il.org Flickr (CC BY 2.0)

Living bridges made of fig tree roots in Cherrapunji, India

When the Indonesian island volcano Krakatoa erupted in 1883, the waves it sent forth crashed into Bantam, some 50 kilometers away in western Java, and flattened forest for a distance of more than 300 meters inland. All that remained standing, said French scientists who visited a year later, were tall fig trees, their bare branches reaching skyward.

Back on Krakatoa there was no trace of life. Much of the island had vaporized, and what was left was buried under a 60-meter deep blanket of ash. Yet before long, several species of fig trees grew there too. They had arrived as seeds defecated by wandering birds and bats. They soon produced figs that drew in more flying animals, which in time carried the seeds of dozens of other tree species. And so, from black lava, a forest grew anew.

The physical strength, resilience and animal magnetism of fig trees are powers we can tap as we grapple with the Earth’s fast-changing climate. As my book Ladders to Heaven (US title: Gods, Wasps and Stranglers) shows, humanity has long benefited from these trees as sources of materials and medicines, food, shade and security. As the world warms, we may need them more than ever.

That’s certainly true in the Indian state of Meghalaya, the most rain-soaked inhabited place on Earth. The Khasi and Jaintia people who live in the forested hills there train the aerial roots of Ficus elastica fig trees into living nets that prevent landslides and living bridges that save lives when monsoon rains turn streams into raging torrents.

Some of these bridges are thought to be centuries old. By contrast, steel suspension bridges last just a few decades. Bangalore-based architect Sanjeev Shankar says fusing fig roots with steel bridges could create stronger, longer-lasting hybrid structures. He also thinks people in other countries could use the living roots of their own local Ficus species to create structures that build resilience to extreme weather.

But fig trees aren’t only valuable in wet places like Meghalaya. They are also helping people adapt to the growing threat of drought. Farmers in Ethiopia, for instance, are embracing a fig species called Ficus thonningii. These trees need no irrigation, yet their leaves provide vital moist fodder for livestock. They enrich the soil with leaves that fall and decay, and they improve the growth of crops planted in their shade instead of the blazing sun.

Research by Mulubrhan Balehegn and colleagues at Mekelle University shows that planting this species instead of the usual fodder crops can boost production by 500 percent, while reducing inputs of water by 95 percent. Goats that eat the fig tree’s leaves produce more and better quality meat than those given only commercial feed.

Over the past decade, Balehegn and his colleagues have encouraged 20,000 households to plant this tree. They hope farmers will follow suit in the 33 other African countries where Ficus thonningii grows, and urge people to take similar approaches with fig trees in arid areas of India and China.

Crucially, planting fig trees doesn’t just improve livelihoods and help people adapt to the changing climate. By storing carbon, the trees can also play a part in slowing the rate of warming. All trees store carbon as they grow, but—as on Krakatoa—fig trees also encourage the growth of other tree species because their figs attract a diverse range of seed dispersers. In Costa Rica, Thailand and South Africa, researchers are harnessing this power by planting fig trees to accelerate reforestation on logged and mine-scarred land.

Elsewhere, people have traditionally used the presence of Ficus species to divine water, helping them decide where to plant crops or dig wells. Others have planted, or left standing, large fig trees as natural umbrellas against the heat, or have stored dried figs to turn to in times of drought and famine.

In fact, fig trees were among the first plants people domesticated. They have been helping people survive in hot and arid lands for thousands of years. As the world warms, the edible fig (Ficus carica), now grown in at least 70 countries, will grow in importance.

Rising temperatures also pose challenges to fig trees and the tiny wasps they depend on to pollinate their flowers. But this relationship between the plants and their pollinators has endured for 80 million years longer than humans have walked the Earth. The fig trees survived the extinction event that saw off the giant dinosaurs, and lived through periods warmer than what we experience today.

By contrast we are new here. Our future is made insecure by the slow pace at which we are removing carbon from the atmosphere, and our limited capacity to adapt to the resulting climatic change. The good news is that fig trees can help us to do both.

This post was first published (here) by Scientific American.

Photo credit: 2il.org Flickr (CC BY 2.0)

Read more about fig trees in my book Ladders to Heaven (published in North America as Gods, Wasps and Stranglers). For a summary and reviews from Annie Proulx, Deborah Blum, Michael Pollan, Sy Montgomery, Simran Sethi, David George Haskell and others, visit this page.

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Sit down, chase some coral, then get up and act

Gulf_of_Eilat_(Red_Sea)_coral_reefs

If you’ve not yet seen the award-winning documentary Chasing Coral, I urge you to watch it as soon as you can. It is a powerful illustration of what we are doing to the planet and why we need to wake up and act. It is inspiring, illuminating and even funny in places.

Coral reefs sustain a quarter of all marine life and directly support the livelihoods of more than half a billion people. They are a source of medicines, such as cancer drug prostaglandin. And they protect coastal communities from storms because the skeletons they form create a living breakwater that constantly grows and rebuilds itself.

But corals are in big trouble. The biggest threat they face come from global warming. That’s because the oceans absorb most of the heat our greenhouse gas emissions are trapping in the atmosphere. As the seas warm, the corals eject the tiny plant cells that live within their tissues. Without the plant cells, the corals turn white — they ‘bleach’ — and then they die.

Chasing Coral follows a team on a quest to record the first ever footage of this process unfolding in real time. There’s a poignant moment in the film when team member Zack Rago is scuba diving on Australia’s Great Barrier Reef. He turns to the camera to show a note he has written with his underwater pen. It reads: “This is the hardest dive I’ve ever had to do.”

Rago, a self-identifying ‘coral nerd’, was stung by the effect of going into the sea each day for a month and seeing corals die from one day to the next, of seeing “flesh, living tissue, rotting away”. He was filming in 2016, the year in which 29 percent of the corals on the reef died. The following year another 22 percent perished.

Coral bleaching is now a worldwide phenomenon. At current rates of global warming, all of the world’s corals will be gone in 30 years, or as Ove Hoegh-Guldberg, Director of the Global Change Institute at the University of Queensland, puts it: “In our lifetime, on our watch”.

The film also follows Rago as he meets his childhood hero, Australian coral expert John ‘Charlie’ Veron, who has been diving on the Great Barrier Reef for 45 years. Veron tells Rago to never quit raising awareness of the threats to corals. “You have to keep at it,” he says. “Otherwise you’re not going to like yourself when you’re an old man. You’re going to like yourself much more if you can say, well, I sure tried to turn that around.”

I feel the same. I’ve been talking and writing about the damage we are doing to the planet for a long time now and I’m not going to stop. But sometimes it feels like nobody is listening, that everyone thinks someone else is going to solve these problems for them.

After the screening of Chasing Coral I saw yesterday, host Anjani Ganase of Wild Tobago and the Global Change Institute pointed out that people often ask what individuals can to do change anything. That’s the wrong way of thinking about it, she said. It is when we are vocal, when we come together that we can build a better future. “There’s no individual in this game,” she said. We are all in this together.

If you have Netflix you can watch Chasing Coral now. If not, you can get a free licence for a public screening.

Photo credit: Daviddarom / Wikimedia Commons

Frying eggs, flying foxes, dying wasps, crying shame

Crack an egg in a pan, turn up the heat and you can witness a kind of magic. In just seconds the viscous egg solidifies. Despite the rising heat, it’s the opposite of melting that occurs. I was a teenager when I heard a biology teacher explain this paradox: “The egg is full of proteins and the heat has denatured them”. Denatured. The word was new to me. Twenty-five years later I find it is a fitting descriptor of more than just wayward proteins.

My teacher explained that every protein has a temperature at which it will function best. Too hot or too cold and the protein’s shape can buckle or break. It will no longer be able to bond with other chemicals. It will cease to work. I think about that fried egg often when I consider what rising temperatures could mean for the planet.

We know that when people die of heat stroke, part of the problem is that some of their proteins have denatured. Could our cells become our jailors?

The proteins inside us and every other living thing vary greatly. Some tolerate heat better than others. Others begin to destabilise at just a couple of degrees warmer than normal. It is not the average protein that poses a problem, but the weaker links, those most liable to destabilise in extreme heat. We don’t know yet which of them are also critically important – to our food crops for instance.

As the world warms, what will happen to the millions of different proteins in the millions of different species, from spores to sperm whales, soil bacteria to sunflowers? These invisible structures are central to life itself. They give shape not only to hair and to horn but also to hormones and enzymes and DNA. They are the messengers and mechanics that control and correct processes in and between cells. Like the gaps in music that make the beats thrilling, these in-between places are where wonder is born.

It’s the same between species. Life is not a zoo of caged individuals living in isolation but a web of shared destiny. And while activists go on about polar bears or other creatures in danger, I am more curious about what climate change could mean for the way species interact and provide us gifts as a result. It’s been on my mind since the early years of my career when I lived in a rainforest in Borneo and studied the most fascinating of plants, the strangler figs.

Every one of the 750 or more species of fig trees depends for survival on its own species of tiny wasps to pollinate its flowers. The wasps in turn depend on the figs, the only places in which they can lay their eggs. This mutual reliance combines with the wasps’ short lifespans to ensure figs are available year-round, and because of this they sustain more species of birds and mammals than other plants. In return for the fig flesh those creatures disperse the trees’ seeds, and provide the same service to thousands of other rainforest plants. These interactions between fig trees and animals help to sustain the great rainforests of the world.

What does this have to do with climate change? Researchers have shown that just a small increase above current temperature levels will shorten a fig wasp’s life to just a couple of hours – not enough time to find a fig, pollinate its flowers and lay eggs. No pollination would mean no ripe figs for animals to eat, and this would mean fewer seeds get spread from place to place. Tree species that form a key part of the forest and its capability as an ensemble to lock away carbon are likely to suffer.

The tiny wasps are frail but some of the fig trees’ bigger partners are at risk too. They include fruit bats called flying foxes that can carry seeds 50 kilometres or more before pooping them out, making them some of the most effective seed dispersers around. Their vulnerability became clear early in 2014 when thousands of them fell dead from the sky during a blistering heat wave in Queensland, Australia. For both the bats and the fig wasps, the heat was too much. It will have interfered, at a cellular level, with proteins that cooked and then closed for business. These snapshots suggest trouble in store for the fig trees and the forests, whose fates entwine with our own.

Ecology teaches us that no species is an island. It’s a lesson our leaders seem to have skipped. It shows us we’re all in this together, the fig wasp and the fruit bat, the you and the me. That’s what makes the human fingerprints all over climate change all the more ironic. As we develop societies ever more distant from nature to protect ourselves from its wild whims, we risk unleashing upon these denatured societies powers we cannot hope to control or even predict.

This post reproduces my contribution to Culture and Climate Change: Narratives, which launched on 24 June at the Free Word Centre. The whole book is available for free and anyone can reproduces its articles under a Creative Commons Licence.

It will take hundreds of Al Gores or millions of ‘little people’ to overcome the political inertia on climate change

Journalist Darren Samuelsohn has quoted me in a question he put to the former Vice-President of the United States, Al Gore in a rare two-hour interview for Politico magazine.

Politico Magazine: During the “24-hour project” [a Gore-led October 2013 effort to raise awareness about climate change], there were a lot of critics who said it didn’t get the right message out, that you weren’t the best messenger, either. There was one response in particular that summed it up that came from Mike Shanahan, from the International Institute for the Environment and Development: “Climate change needs a Gandhi or a Martin Luther King or a Mandela and Al Gore is none of those.” What do you say when critics note that Al Gore as a person polarizes half the country; you need someone different to lead the cause?

Al Gore: It’s not about me. And I’ve never tried to make it about me. And far be it from me to disagree with someone who says I’m not Gandhi or Martin Luther King Jr. or Nelson Mandela. I have to plead guilty to that charge. I wish that I had the greatness of those three men.

But I’m enough of a student of history to know that Martin Luther King Jr., to pick one example, was considered extremely polarizing and was by many hated and despised. And in the South it was not uncommon to hear people trying to appear reasonable on civil rights but nevertheless digging their heels in, who’d say, “Well, if King would just get out of the way this would just happen.” I think that whoever puts his head up above the trenches and says, “We’ve got to do this” is going to attract the ire of people who don’t want to do it. And there are plenty of them.

Samuelsohn had reached out to me because I had written a post here about Gore back in 2011. Ahead of his interview with Gore, Samuelsohn wanted to know if my views had changed. For the record, here’s the full text of my response to Samuelsohn.

History should judge Gore well, as someone who staked much upon his belief that climate change was an issue to tackle and who worked hard in public and private to convince people that this is a battle we can all fight together.

Too few people with his power and political connections have been so bold. That said, Gore lacks some credibility as a climate-change messenger as his interest in the subject has seemed to come and go. Nor should this task fall upon one man’s shoulders, even if they are as big as his. It will take hundreds of Gores or millions of ‘little people’ to overcome the political inertia on climate change.

Where Gore can have the most impact is not in other countries but at home, by working to show that action on climate change is a bipartisan issue that all Americans can get behind. It needs to be less about Gore the personality and more about Americans doing the right thing.

You can read Darren Samuelsohn’s full interview with Al Gore here. It is an enlightening read and it ends with Gore in an upbeat mood.

Al Gore: It’s clearly wrong to do what we’re doing. It’s clearly right to change. We will change. It’s just a matter of time. And again, how long? Not long.

Climate change: Teens teach where others don’t reach

A 13-year-old girl interviewed me last week about my job, through which I communicate with journalists around the world about climate change and other environmental issues. She is part of the generation that worries about such things, according to a new poll. It’s the generation from which real leadership on climate change will emerge.

The UNICEF poll – published on 17 April 2013 — found that three-quarters of British 11 to 16-year-olds were concerned about how global warming will change the world. Two-thirds of them also worried about how climate change would affect other children in other parts of the world.

The poll said these concerned children want their government to act on climate change, but they may need to do that themselves. They will need to be teachers too. This is because the British government had decided to remove climate change from the national curriculum for children under 14. It’s a move that scientists, business leaders and others have criticised as “unfathomable and unacceptable”.

It is more than this. Under the UN Framework Convention on Climate Change — which was agreed in 1992 and entered into force in 1994 — nearly 200 governments agreed to promote actions to develop and implement “educational and public awareness programmes on climate change and its effects”.

Their track record so far has been pitiful. By 2010, only Belgium (on behalf of the European Union), Colombia and the Dominican Republic had submitted reports on their activities. When I wrote about this on Under the Banyan in 2011, most of the readers from around the world who commented said their governments did little or nothing to educate their population on climate change.

More recently, some countries have begun to act. Last year, the government of El Salvador made it mandatory for all educational institutions to incorporate climate risks into their teaching materials. In March this year, the Dominican Republic launched a national teacher training programme on climate change. In the United States, new science teaching standards will include extensive lessons on human-made climate change. Suddenly it looks like British children are being left behind.

Kenya’s new national climate change action plan – unveiled in March 2013 — called for climate change and its impacts to be on the primary school curriculum. It says students at secondary schools also need “to be equipped with skills to support a future climate resilient economy” and that “at university level, climate change should be infused into the various professions.” It says:

 “Civil engineers, for example, need to learn how to design and develop structures that can withstand climate shocks. Doctors need to be aware of the effects of climate change on human health, while architects should have the skills and training to design houses that are climate-proofed and energy efficient. Teachers ought to be equipped with knowledge about climate change in order for them to be suited to teach a curriculum that integrates climate change across all subjects taught at schools in Kenya. Whereas it is already the case that climate change as a subject is now being taught at Kenyan universities, there will be a need for institutions of higher learning to develop policies to ensure that all students educated there are familiar with climate change, its impact and strategies for adaptation and mitigation.”

These are all initiatives to applaud. But given that governments took nearly 20 years to act upon pledges to educate their people on climate change, it seems clear that the people will also need to teach themselves.

While parents have a role to play in climate change education, they find it hard to be truthful about climate change without scaring their children. The Yale Forum on Climate Change and the Media published a long essay on this topic. But where governments fail and parents feel unsure, young people can talk with confidence to their peers.

They include Esther Agbarakwe, the 19-year old Nigerian who each Wednesday uses Twitter to coordinate a live conversation between climate experts and anyone worldwide who is interested (see #climatewednesday). Or 18-year old Merna Ghaly from Egypt, a leading member of the Arab Youth Climate Movement. This month Newsweek Magazine, in the United States, named her one of the top ‘125 Women of Impact’, alongside heads of state and business leaders. Or Esha Marwaha, the 15-year old student and member of the UK Youth Climate Coalition who organised a campaign that called on the UK Department for Education to reinstate climate change into the school curriculum.

These three young women are just some of the members of new band of passionate communicators who are not waiting for teachers or parents or politicians to lead the way. They are growing in number and are increasingly connected. They cooperate internationally in ways that nations will need to if they are to tackle climate change. They are the future and they are here today. More power to them.

This post is based on the 27 April editorial I wrote for The Thumb Print magazine (India).