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Wednesday, August 1, 2012

Team Banana

Last month, in Tlapacoyan, our team was challenged to create a better way to pack fruit and get it to Mexico City with less spoilage. Yihad Ghattas is our meticulous Colombian urban planner. Our architect, Roberto Ferrar, is from Mexico City, and I am the biologist. We start by asking what kinds of fruit are grown in the region. What are the real problems faced by the growers? We interview several locals. The range of fruit is bewildering, varying fantastically in size, durability, and requirements for ripening, humidity, and temperature. Lychee, mango, oranges, limes, grapefruits, papaya, avocado, pumpkins, mamey, sapote, guanabana, melons, and even coffee…how can we possibly come up with a solution for all these? Chucho, a former grower, tells us that the most important fruit in the region is the banana. And the Tlapacoyans are not happy about the way it is grown.

Tlapacoyan is a region of stunning beauty, beloved by its people. Here, the Rio Bobo churns forcefully through a dramatic primeval landscape of ancient figs and giant ferns, dotted with colorful orchids and bromeliads, dripping with pulsing slime molds, and laced with the intricate webs and nets of an endless array of skillful and patient hunters. Team Banana picks its way carefully through coursing streams of leafcutter and army ants to get to Bobo’s sandy, bouldered shore, framed by towering trees, and littered with the corpses of hundreds of plastic bags.
Banana bags and monoculture

Covering the penca

Over the ceaseless rumbling of the river and the deafening buzz of cicadas, Chucho tells us how to grow bananas. A single violet ‘penca’ balloons perversely from each tree. These are sequestered from insects with a transparent blue baggie, which has the added function of concentrating levels of the banana’s own ethylene, thus hastening ripening. The grower cleaves the penca from the tree with his machete, and the purple bruise fades to sickly chartreuse as the bags are peeled off and discarded, sometimes catching the air to sail off like jellyfish. The bananas are plunged into the ‘carburo,’ a kind of liquid charcoal that serves as artificial ripener, and divided into family-sized bunches. These are placed into a second baggie, stacked into cardboard boxes, and loaded onto an open truck. The trucks rumble off, in a thick cloud of diesel exhaust, toward the enormous distribution center in Mexico City. Days later, the trucks return with the boxes and plastic baggies (which the distributor does not want), and more jellyfish make their way to the shore.The banana trees are planted in endless monotonous waving rows, right to the edge of the jungle. It takes a full year for these ragged shoots to produce. Once the tree yields its solitary fruit, it dies, and the fecund forest floor becomes barren, the soil degraded. The richness of the rainforest depends on the incessant rhythm of scurrying feet, scrambling mouths, and pulsing decay. When this dance is interrupted, the nutrient cycle stops. It is difficult to start the music back up.

 The Tlapacoyans want to feed their families, which extend voluminously backward and forward in time to include ancestors and grandchildren. Their livestock grazes peacefully between the ancient temples, sacred ball-fields, snaking stone walls and manicured waterways built by the Old People three thousand years ago, in a past that still seems present. And not because they left their plastic bags lying around.

Our task becomes repelling insects, ripening quickly, and packing efficiently, while considering the integrity of the land and maintaining a living for the growers. The bananas must be ready to sell on arrival. The faster the growth-to-market cycle, the more money to be made. Profit, People, Planet, the three 'P's. Especially Profit. It’s time to biologize the question: How does Nature protect, pack, and preserve? We brainstorm a long list of possible organisms and structures, and observe that Nature goes into high gear protecting, preserving, and packing its most precious cargo. Packets of priceless information are horded jealously in genetic vessels of all kinds: eggs and larvae, nests of birds and colony insects, seeds, pods, and cones, even spittlebug foam.

We discard coconuts in favor of honeycomb, a brilliantly lean modular system for protecting larvae, preserving nectar, and packing honey. The hexagon permits no wasted space, and cells and bubbles naturally form hexagons when pressed together. Buckminster Fuller, the genius behind the geodesic dome, knew this. A honeycomb of lightweight, durable, locally available, and ultimately biodegradable bamboo boxes will stack perfectly in the trucks. We can even fold them down for the return trip, using a simple locking rod patterned on the flamingo knee joint. Roberto turns engineer, working the numbers, making blueprints, and constructing a passable model from BBQ skewers and scotch tape.  

Our Champions: the Bonete pod and the multi-storied forest

More champions: Sea sponge and spider web

Can we combine this with a peapod duffel-bag structure on the penca to keep out the insects? We walk through the forest, searching for suitable seedpods. We come up with Jacaratia mexicana, the Bonete. This tree grows in the seasonal rainforest, and sports a tough cone-like waterproof ‘berry’, which in cross-section appears as a pentagon. Moisture collects on the exterior and is shunted away to the ground. The berry stays dry until the seeds are ready; the pod breaks free, falls into the moist ground below, and dehisces at huge force, splitting its sides to fire the seeds out for germination. Can we make a bag inspired by the Bonete?

And what about ripening? At home, I tuck unripe fruit in a brown paper bag next to a red apple. The apple emits ethylene, ripening its companion. We find Jose Carlos Cervera, a young Yucateco botany professor who spends his days measuring the exact gaseous inputs and outputs of a couple of individual succulent plants. Grown far too intimate with the secretions of his subjects, Jose hates plants. He’s our man: he tells us about the wide assortment of 'climacteric' fruit that produce ethylene: peppers, pumpkins, bananas, avocados, all locally available. We can grow these alongside the bananas, mimicking the multi-storied forest around us, and simply chuck a few into each box as we pack. But which one? Peppers like to be dry, and avocados are big and shady. Nobody seems enthusiastic about sapote. We settle on pumpkins, grown throughout the year, available in many sizes, and thriving on neglect. In fact, the ancients traditionally planted maize this way, alongside squash and beans, which fix nitrogen into the soil.

Honeycomb and flamingo knees

We need to pull this system of disparate parts together. The sea sponge comes to mind: a porous bag of tissues inside a tough exterior tube. Water draws nutrients through the tube, to be filtered for consumption by the porous bag. Or spider webs, passively filtering insects while the breeze passes through. We can use these strategies to keep insects out, while drawing ethylene in. Our plan emerges: a mesh bag, surrounded by a waxy canvas tube, is tied over the developing penca. The bottom mesh receives ethylene from the pumpkins growing below, while denying entrance to insects. The penca is cut down and separated into bunches. Our hexagonal bamboo structure goes into the bag, and the bananas are packed into it, along with a few small pumpkins. The bag is closed and loaded onto the truck. After unloading, the units are folded down so other items can be brought back to sell in Tlapacoyan. When the grower returns home, he is greeted by the delicious smell of frijoles, platanos, y calabaza. Con mucho gusto, Tlapacoyan!
Team Banana: Roberto Ferrer, myself, and Yihad Ghatta


  1. Tamsin, this is a wonderful story... I've been thinking we need to share the incredibly innovative ideas coming out of biomimicry workshops and trainings. Thanks for sharing this one!

  2. Thats a real example of symbiosis, collaborative team are fundamental! keep doing this wonderful exercises. Yucatan, is one of my favorites places from my country...

  3. I feel honored to have seen the presentation of Team Banana Biomimic. An Architect, a Biologist, and an Urban Planner... It just doesn't get more diverse or brilliant. Y'all should consider manufacturing your bananerific packaging product, me thinks.

  4. Gorgeous. You made it so beautiful.