Eating Tasty Flying Termites in Zimbabwe

Eating Tasty Flying Termites in Zimbabwe

By Tatira Zwinoira • FEB 22 2018

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Why you should care

Because if you want them fresh, there’s just one month to try them.

Growing up, my favorite time of the year was December. And before you start thinking, “This is another Christmas story,” well, it’s not. This was the one month of the year I could spend with my grandmother cooking something that was available only around that time. It was so fun preparing this particular meal because first we had to look for and capture it.

The special treat? Flying termites, or ishwa (flying alates), are Zimbabwe’s second most popular insect cuisine after the mopane worm. But the tasty and juicy ishwa are actually a healthier option, packing an extra protein punch. Found in the provinces of Mashonaland East and Central, Masvingo and Harare, the meaty little delicacies have been consumed by many tribes and cultures across the country dating back centuries, according to the Natural History Museum of Zimbabwe. Fresh ones are available only during the insect’s annual mating flight, which occurs in the second month of the rainy season.

The dish is often served with the country’s traditional staple food sadza (cooked maize meal), with vegetables and gravy on the side.

What makes the termites so tasty is the mixture of protein and fats, says chef Honest Danda, who has cooked termites throughout his 10-year career (including at one of Zimbabwe’s top hotels, Rainbow Towers). This is why ishwa are never cooked with oil. “Growing up in a rural area, we used to harvest ishwa from a termite mound. My mother taught me how to cook them,” Danda says. And that’s how he started preparing them: in an open frying pan over a fire.

The trick in frying ishwa, Danda explains, is stirring continuously as soon as they’re in the pan. This helps get the wings off the insects faster — and keeps them from flying away. While there is nothing wrong in eating the wings, the dish is usually served without them. Once most of the wings are off, the ishwa are removed from the pan to dry. Then they’re returned to the pan, this time with a bit of salt and water, depending on the quantity, and turned in the salty water until it evaporates. Then the termites are dried again prior to serving.

Although traditionally a rural favorite, ishwa are so popular now that a number of shops in the suburbs of Harare such as Belvedere, Avondale, Westgate and even the central business district are beginning to sell them precooked. The growing demand is in response to termites being marketed as a healthy choice. Some resorts, traditional restaurants and food outlets are adding flying termites to the menu. On occasion, even posh hotels such as Rainbow Towers offer the dish around December. The dish is often served with the country’s traditional staple food sadza (cooked maize meal), with vegetables and gravy on the side ($1–$2).

Initially, you may try ishwa out of curiosity, but the taste might just get you hooked. The first bite explodes with a rich, oily and nutty flavor. As you begin to chew, the greasy goodness from the body releases, giving it a stir-fried kind of taste. That delicious taste, that’s why I eat them.

www.ozy.com

BIOMIMETIC ARCHITECTURE: Green Building in Zimbabwe Modeled After Termite Mounds

Architecture

Biomimicry’s Cool Alternative: Eastgate Centre in Zimbabwe
The Eastgate Centre in Harare, Zimbabwe, typifies the best of green architecture and ecologically sensitive adaptation. The country’s largest office and shopping complex is an architectural marvel in its use of biomimicry principles. The mid-rise building, designed by architect Mick Pearce in collaboration with Arup engineers, has no conventional air-conditioning or heating, yet stays regulated year round with dramatically less energy consumption using design methods inspired by indigenous Zimbabwean masonry and the self-cooling mounds of African termites!

Termites in Zimbabwe build gigantic mounds inside of which they farm a fungus that is their primary food source. The fungus must be kept at exactly 87 degrees F, while the temperatures outside range from 35 degrees F at night to 104 degrees F during the day. The termites achieve this remarkable feat by constantly opening and closing a series of heating and cooling vents throughout the mound over the course of the day. With a system of carefully adjusted convection currents, air is sucked in at the lower part of the mound, down into enclosures with muddy walls, and up through a channel to the peak of the termite mound. The industrious termites constantly dig new vents and plug up old ones in order to regulate the temperature.

The Eastgate Centre, largely made of concrete, has a ventilation system which operates in a similar way. Outside air that is drawn in is either warmed or cooled by the building mass depending on which is hotter, the building concrete or the air. It is then vented into the building’s floors and offices before exiting via chimneys at the top. The complex also consists of two buildings side by side that are separated by an open space that is covered by glass and open to the local breezes.

Air is continuously drawn from this open space by fans on the first floor. It is then pushed up vertical supply sections of ducts that are located in the central spine of each of the two buildings. The fresh air replaces stale air that rises and exits through exhaust ports in the ceilings of each floor. Ultimately it enters the exhaust section of the vertical ducts before it is flushed out of the building through chimneys.

The Eastgate Centre uses less than 10% of the energy of a conventional building its size. These efficiencies translate directly to the bottom line: Eastgate’s owners have saved $3.5 million alone because of an air-conditioning system that did not have to be implemented. Outside of being eco-efficient and better for the environment, these savings also trickle down to the tenants whose rents are 20 percent lower than those of occupants in the surrounding buildings.

Who would have guessed that the replication of designs created by termites would not only provide for a sound climate control solution but also be the most cost-effective way for humans to function in an otherwise challenging context?

inhabitat.com

Termites zimbabwe

How do you cool a building without air conditioning?

In nature, termites build skyscraper-like mounds that are ventilated by a complex system of tunnels. By emulating the ingenuity of termites, Zimbabwean architect Mick Pearce used an approach called biomimicry to design a natural cooling system that harnessed nature. The result is an architectural marvel that achieves 90 percent passive climate control by taking cool air into the building at night and expelling heat throughout the day.

In this first installation of the Decoder series, see how the Eastgate Centre in Harare, Zimbabwe utilizes a termite-inspired climate control system. To learn more, read “Termite Climate Control” from the May 2018 issue of National Geographic magazine.

See how termites inspired a building that can cool itself

How do you cool a building without air conditioning?

In nature, termites build skyscraper-like mounds that are ventilated by a complex system of tunnels. By emulating the ingenuity of termites, Zimbabwean architect Mick Pearce used an approach called biomimicry to design a natural cooling system that harnessed nature. The result is an architectural marvel that achieves 90 percent passive climate control by taking cool air into the building at night and expelling heat throughout the day.

In this first installation of the Decoder series, see how the Eastgate Centre in Harare, Zimbabwe utilizes a termite-inspired climate control system. To learn more, read “Termite Climate Control” from the May 2018 issue of National Geographic magazine.

video.nationalgeographic.com

Termite Control

A termite control service and proofing needs a professional. We are here.

Termite control and treatment should be taken seriously if you are to protect your property. Of all the pests known to man, termites present the most danger to humans. They destroy property worth millions of dollars.

They eat cupboards, skatings, ceilings and anything that comes their way if it just tastes good resulting in huge financial losses. The most sad thing is most people do not know how dangerous termites are and only realise when it is too late. Homeowners should know how to identify signs of termite infestation

Most people build houses without even taking important measures to prevent a future termite attack. They do not know it is important to do pre-constructional termite proofing which is an exercise done when building your house. Even if they do, they do it inappropriately or use over-the-counter chemicals that will not achieve any protecting against termites in the long term. Therefore, homeowners or indiv />

Once termites target your house foundations, walls, roof, ceiling and beams, establishing a network of tunnels and nests, in most instances you won’t suspect anything until it is too late. Termites will only rise to the top where they are seen when the damage is in a difficult and expensive stage for you. You would not want it to be like that.

Types of Termite Species in Zimbabwe

There are over 15 known species of termites in Zimbabwe. Worldwide figures stand at 2 600. With this huge number, new types are even being discovered all the time.

Termites live in colonies and they are organised creatures. Each member performs a specific job. In a typical caste system, we have workers, soldiers and the reproductive queen.

The workers make up the largest number of individuals within a colony and they do most of the work. The solders defend the colony against invaders and the queen is responsible for producing members.

Our Termite Treatment Solution

Therefore, the first important thing is to be informed about the importance of termite prevention methods and how to do it in the event you have a termite problem.

Pest Portal has invested quite a lot in termite knowledge, behaviour and termite treatment methods. The period we have been in business has helped us to learn and come up with effective termite control methods.

Termite Control Assessment

When you give us a call, we schedule a termite assessment. We agree with you to come and see what is happening. What we need to know during our assessment is:

  • The nature of your termite problem
  • How long you have been having the problem.
  • The types of termites that are giving you problems.
  • Where these termites are coming from.
  • The extent of the termite damage to your property.
  • Helping you understand what is happening.
  • Any other important information

Preparation of Quote

When we have collected all the above information, we then prepare a formal quote. Our quotations are free in Harare. If you agree with the price on the quotation, you then schedule a date and time you need us to do the job. Schedule a free termite assessment today

Understanding the Source

For one to effectively control termites or any pest problem, it is important to understand the source of the problem. Termites come and have their home in a nest/mound/zvidzere/churu. Have you seen one in your property? If you have one, chances are that this is where your problems are coming from. At the termite mount, this is where the queen will be, breeding and laying more eggs. In Zimbabwe, the common termite nests are those of Harvester termites and white ants. From the nest, the workers will travel from this looking for food. In most situations, they end up in your kitchen, eating cupboards and house skatings. Eliminating the problems at the source at most times will stop the problems in your home.

Termite Control Methods

At Pest Portal, we employ a number of termite treatment methods to make sure we control and treat the termites. Once we have identified the source of the termites, our treatment method will be targeted at that source.

Thermal Treatment

Thermal treatment involves using a petrol powered machine that pumps some poison into the nest, therefore killing the termite queen. When the termite queen is killed, the entire colony will be eliminated.

Liquid Termiticides & Toxins

Liquid poisons and other toxins are also applied in the nest to ensure the nest will be controlled of all the termites.

Spot Treatments

House skatings, cupboards, ceiling beams and house foundations are also sprayed with termiticides that will stop any further termite attack.

Follow Ups and Guarantees

After our termite treatment, follow ups are done to ensure the methods used are working. When a nest is treated, no more termites should be seen on that nest. This means it should stop building. When it stops building, it therefore means the problem has been controlled.

Our Guarantees are as follows:

Harvester Termite Nests – 5 Years
White Ant Nests – Lifetime Guarantee
House Skatings, Cupboards and Ceiling – 5 Years

www.pestportal.co.zw

The termite mound: A not-quite-true popular bioinspiration story

I traveled extensively over the summer; to Austin, TX, all through Western Europe and back to Illinois. All the while I was working on this blog post about bioinspired air-conditioning, which was appropriate because everywhere I went I seemed to have to suffer through heat-wave after heat-wave.

While wishing for Europe to have more air-conditioning units (especially in class-rooms and lecture halls), one of course wonders if that would only exacerbate the problem and make summers even hotter. Progress is constantly being made on making air-condition units more compact, more energy efficient, and thus more environmentally friendly. Inspiration on how to accomplish this has been already been found in natural systems.

Recently Brian Clark Howard wrote an interesting and popular article for National Geographic entitled: “5 Natural Air-Conditioning Designs Inspired by Nature”. Arthropods (termites & ticks) were prominently represented on this list. However, I would like to provide a little bit more detail and corrections to the NG’s list.

The insect examples touched upon in the NG article is that of the termite mound. The most famous architectural example of biomimicry or bioinspiration is the Eastgate Centre Building in Harare, Zimbabwe, which opened in 1996. Architect Mick Pearce and the firm Arup were supposedly partly inspired to build a building suitable for a tropical climate by considering the locally present termite mounds, and build their vision using locally available materials.

Anyone who is even the slightest bit interested in biomimicry knows of the Eastgate Centre, but since the political and economic situation in Zimbabwe has probably only deteriorated since 1996 I was wondering if it was actually still standing and still used as the commercial center it had been envisioned as. So I took my questions to Twitter: [View the story “EastGate Building Harare, Zimbabwe” on Storify]. Turns out that the Eastgate building is still used and stands out prominently in the heart of Harare (and as @ardeans pointed out the building is located right on Robert Mugabe Road, sigh). One of the occupants is actually the United States Embassy.

It is just kind of too bad that the building is based on incorrect biology. Or is it?

First a little bit of background about the inspirational insect. Macrotermes termites (Macrotermitinae) occur over tropical Africa and Asia. There are about 330 species in this genus of relatively large termites. Most of the species build elaborate mounds. The tallest mounds occur in Africa (max of 30 feet, 9 meters). Macrotermes termites cultivate fungi, and spend most of their time, somewhere deep within the mound. The Macrotermes species that has been studied the most is the African species M. michaelseni.

Flickr user Potjie uploaded this picture of a termite mound in Northern Namibia. (http://www.flickr.com/photos/potjie/3408013097/)

Popular wisdom says that in order to optimize fungus growth the interior of the mound needs to be maintained within the narrow range of 29-32°C. To keep keep within this narrow temperature range, despite of fluctuating temperatures during the day- and night time, the large mounds are not just heaps of dirt but in fact incorporate elaborate ventilation holes and air ducts and air pockets, which drive natural ventilation through convection. And remember, these structures are build by a million tiny insects that behave in an organized manner to come up with an architectural masterpiece, every time.

So no wonder that Mick Pearce, born and raised in Southern Africa, was inspired by the the termite mound to design a building in tropical Harare that would have similar features.

Up until recently two models for the termite mound function were proposed and commonly accepted. In case of mounds that were capped a “thermosiphon flow” was created – basically hot air created by the nest rises to the top of the mound where it gets refreshed and is supplied with water vapor through the porous mound walls. This denser air then is forced down below the nest, where the cycle is repeated.

The second model applies to mounds that have a chimney at the top of the mound that opens to the outside. This arrangement creates induced flow, also called the stack effect. The chimney breaks the surface boundary layer and is exposed to higher wind speeds compared to inlets on the ground. The unidirectional flow draws fresh air from near the ground into the nest, where it passes on through the chimney and ultimately to the outside.

The architects who designed the Eastgate Centre building tried to incorporate both the thermosiphon and induced flow principle into their design. The building has an extensive tube system within the walls and floors that move air trough the building. Heat generated within the building, along with stored heat within the structure, creates a thermosiphon-effect that draws air up and through the rooftops where large chimney stacks are located. These tall stacks are essential for creating an induced flow.

When popular stories about the Eastgate Centre building say that the building works on the termite mound principle they ignore the fact that the building uses low capacity fans during the day, and high capacity fans during the night to keep the air from being too stagnant, effectively replacing the hot air that builds up during the day with cool air during the night. This works well, and avoids having to use expensive air-conditioning technology, but needless to say, no termite mound utilizes fans.

Larger fans run during the night time, these pull the stored heat out of the walls and pushes the heat out through the ducting in the ceiling and walls. By next morning the walls are ready to again store heat. (Drawing by Marianne Alleyne)

The use of fans within the Eastgate Centre. Smaller fans run during the day-time hours (left). They keep the environment within the building comfortable while the walls store the heat from the outside. Larger fans run during the night-time (right), these fans pull the stored heat out of the walls and push the heat out through the ducting in the ceiling and walls. By the next morning the walls are ready to again store heat (Drawing by Marianne Alleyne).

Since 1996 the common assumptions about how termite mounds are ventilated has been refuted by researchers J. Scott Turner and Rupert C. Soar. And they do it (the disproving) in such a polite manner! (see Conference paper, Flash presentation, YouTube video).

Turner and Soar actually measured temperatures in and outside of the mound. It turns out that while termites may be able to dampen temperatures during the day the nest itself actually closely tracks the soil temperature, which ranges from 15 degrees C in the winter and 31 degrees C in the summer. Mounds have clearly a large thermal capacity, but their architecture, their infrastructure, and their ventilation have little to do with the internal temperature at any given time.

In addition, whereas induced flow might work well in tall buildings because the likelihood of a boundary layer gradient between locations is pretty high, it has been shown that induced flow rarely operates in termite mounds, even open-chimney mounds, since they are commonly only about 6 ft tall. There is also no evidence that mound ventilation and nest ventilation are indeed linked. How respiratory gases are moved from the nest to the mound, and fresh air from the outside, through the mound, to the nest, is not well understood.

Now the Eastgate Centre, and other large buildings since then, accomplished what they set out to do – they saved in construction costs (HVAC systems are very, very expensive) and they save on operating costs, all while keeping the inhabitants comfortable. It probably does not matter that they were based on incorrect science, but it does matter that the misconception gets repeated over and over again. If biomimicry and/or bioinspiration want to be considered legitimate fields of study, and not just a feel-good endeavor, then the science that the field is based on has to be solid.

The termite mound should still inspire developers and architects because at it turns out, if we view the termite mound as the analogue of our own, respiratory system (lungs) then we still should be able to design “breathing” buildings that have that walls serve more as membranes rather than barriers.

Turner and Soar not only took relatively simple measurements of the temperatures, they also made plaster casts of the tunnel network of M. michaelseni mounds. They then created horizontal slices of the plaster filled mounds for easier recreation of future 3D models.

Based on these models, which showed actually very little continuous mixing between the air coming down from the above-ground structure and the air from the underground nest, they propose that the termite mound of M. michaelseni is in fact a functional analogue of a lung. And much like the lung the termite mound is far more complex than the simple models we have been using (for an excellent explanation comparing functional organization of both lungs and termite mounds please refer to Turner and Soar, 2008).

This complexity opens up new avenues for bioinspired design based on the termite mound. Termites erect walls that are actually interface directly with the outside and indoor environments – the walls themselves let gases and energy through, it does not form an impenetrable barrier. Buildings that are designed based on correct termite mound architecture should incorporate porous walls and cladding (

skin) systems that incorporate tubes/tunnels through which air and energy can flow. Maybe we can design living buildings that are part of our extended physiology, as much as the termite mound is part of the living-system called the termite colony.

Resources:

I cannot recommend the Turner and Soar paper from 2008 enough. It is a wonderful read. The authors touch on more topics than I mention here (homeostasis, for instance). And again, their debunking of previously held beliefs is done in a way that should be emulated.

  • J. Scott Turner and Rupert C. Soar. 2008. Beyond biomimicry. What termites can tell us about realizing the living building.
  • The same authors also wrote a book chapter on a similar topic. But I have not yet been able to locate: Beyond biomimicry. What termites can tell us about realizing the living building. Chapter 15 in: Industrialised, Integrated, Intelligent Sustainable Construction. ISBN 978-0-86022-698-7. Ian Wallis, Lesya Bilan, Mike Smith & Abdul Samad Kazi (eds). I3CON/BSRIA. London. pp 233-248.

J. Scott Turner has also converted this work into very informative video lectures, such as:

  • Learning from nature: Termite mound lungs and the implications for breathing mines.

For great footage of how the termite mound models were created check out these videos.

I am not, by a long shot, the first to point out how the termite mound is NOT (yet) the perfect poster-child for bioinspiration and biomimicry. Here are two other blog-posts that discuss this very topic:

  • Carl Hastrich on his Bouncing Ideas Blog asked “How is the Eastgate Building not like a termite mound” and if this type of research will encourage us to dive deeper into biomimicry.
  • David Parr on his Biomimicron Blog uses the term Biomythology to describe the Eastgate Centre Building‘s place within the biomimicry arena.

Additional pictures of the Eastgate Centre building in Harare Zimbabwe, click here.

Note: I would like to thank Adrian Smith who a few years ago made me aware of the work by Turner and Soar.

insectsdiditfirst.com

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