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How Fig Trees Restore Forests and Biodiversity
June 28, 2020 Molly Melvin By Molly Melvin My Articles

How Fig Trees Restore Forests and Biodiversity

Widespread reforestation efforts have been hailed as a sure way to mitigate climate change, curtail habitat loss and protect biodiversity. But it's not as simple as sticking new trees in the ground. Read on to learn how fig trees play a central role in bringing deforested land back to life.

In late summer, the smell of sweet, ripe figs floods supermarket aisles, market stalls and greengrocers. As an avid lover of figs, I cut mine into quarters, briefly appreciating the intricate pattern inside before devouring each piece, skin and all. But aside from being a delicious treat, the fig is rather extraordinary: it is not a fruit at all, but a capsule of inverted micro-flowers, known as an inflorescence.

The Fig and the Fig Wasp

Since each fig is, in fact, a ball of clandestine flowers, these need to be pollinated for the plant to reproduce. However, accessing the fig’s floral geode is a highly specialised task, one that is only carried out by a single species of insect: the fig wasp.

Read more on the fascinating fig–wasp relationship in “Figs & Wasps | How Plants and Pollinators Work Together”

You might have thought such a specialised partnership with the fig wasp would hinder the plant, but this unique pollination system has allowed the fig to overcome some of the challenges faced by outwardly flowering plants: figs of the same species don’t need to grow in close proximity to breed. 

Fortified by an exclusive fleet of pollinators, most figs have a highly successful pollination rate, despite what is often miles between fig plants of the same species. In search of the right fig, fig wasps will fly vast distances, sometimes more than 10 km – further than any other known pollinator.1  

Fig Trees Thrive In Diverse Environments

This unique ability to reproduce across long distances has given the fig tremendous adaptability. With solitary fig plants still able to reproduce, figs have radiated throughout the natural world; evolving into hundreds of unique species suited to a variety of environmental niches. Ficus, the fig genus, comprises more than 850 species, making it one of the world’s most varied plant families. 

Figs come in all shapes and sizes and have been found in some of the most remote corners of our Earth; from mountaintops and rainforests to deserts and volcanic islands. They can be woody trees, shrubs or vines.2 Some species, known as giant banyans, grow to be so large, a single plant can be mistaken for an entire forest. The largest specimen of which grows in India, spanning over four acres. The plant’s canopy is so expansive, it’s said 20,000 people could stand beneath it.3

How Fig Trees Support Biodiversity 

The diversity and widespread availability of fig plants have made them a prolific food source for surrounding wildlife. Unlike the majority of plants which produce fruit seasonally, Ficus can bear fruit all year round. This is owed to the unique fig–wasp relationship. To ensure emergent female wasps always have a fig to nest in and pollinate, the plant must continually produce fruit. After a fig has been pollinated, it takes roughly 1-2 months to ripen and become edible. This means that, when seasonal fruits are sparse, there is always a fig tree with ripe fruits for frugivores (fruit-eating species) to fall back on during leaner times.4

Figs Are A Keystone Species

A huge variety of frugivores, from birds to squirrels, reptiles to monkeys and even our pre-human ancestors, have depended on the fig for survival.5 A study from 2001 revealed that globally, a staggering 1300 bird and mammal species consume figs, sustaining more wildlife than any other known fruit.6 Because of the critical role figs play in maintaining wildlife populations and supporting ecosystems, the plant is what’s known as a ‘keystone species’. In the words of tropical ecologist Daniel Janzen; “Who eats figs? Everybody”.7 For this reason, former fig biologist Rhett Harrison has argued Ficus is one of the most important plant families in tropical rainforests.1 Remove them from the forest, and you risk disrupting the entire ecosystem. 

Bringing Deforested Land Back to Life

In tropical climates where most fig species grow, many if not all frugivores have at some point depended on the fig for survival. Keeping surrounding wildlife alive and thriving has direct benefits for the health and diversity of forest ecosystems. The pervasive dependence on figs among frugivores has meant the plant has played a central role in encouraging the regeneration of deforested landscapes.8  

Ficus are an extremely resilient species and often one of the first to emerge on deforested sites. Attracted by the prospect of a juicy reward, frugivores flock to a fruiting fig plant, bringing with them seeds from plants they’ve eaten and encountered elsewhere. Milling around a bountiful fig tree, frugivores deposit these seeds – either in their droppings or by shedding those attached to their bodies, thus introducing a complex and diverse range of plant species back into the system. The result: healthy and dynamic regrowth.9

Fig Trees Can Help Restore Land

Tropical rainforests are the richest terrestrial ecosystems on Earth. While covering just 2% of the world’s surface, rainforests are home to 50% of the planet’s land-based biodiversity.10 Trying to replicate this incomprehensible variety, let alone introduce it back into deforested plots, remains one of the fundamental challenges for ecologists worldwide. 

“But what you can do”, Nigel Tucker, a consulting environmental scientist, tells me, “is create the conditions where that complexity can come back by itself”. By drawing local seed dispersers to barren plots, figs act as a catalyst, accelerating the forest's natural recovery process: ‘Figs bring diversity to the forest that you wouldn’t achieve through planting it yourself”. For this reason, Nigel suggests that at least 10% of the plants used in tropical-reforestation projects be fig saplings.11

In Thailand, biologist Steve Elliott of the Forest Restoration Research Unit is even testing the use of drones to deposit fig seeds (and others), across degraded sites. A drone, mounted with an air gun, can sow a hectare of deforested land in under 30 minutes – a task that would take four people six days to complete.12

Repairing Nature with Nature

The fig presents a profound message on the vital coexistence between living beings and, within this, a lesson for how we can address some of the environmental challenges we face. If we can harness the resilience, adaptability and natural magnetism of the fig, the plant can help us repair lost forests, protect biodiversity and curb the Earth’s fast-changing climate. 

So next time you bite into a fig, will you take a moment to marvel at the plant in all its glory?

June 28, 2020 Molly Melvin By Molly Melvin My Articles