By Maf Sheldon
Botswana’s Kalahari, an illustrious savanneural vista, setting for the world’s largest land mammals, and its most charismatic predators.
The sun sinks past the edge of the firmament, twilight from magnolia white to magenta. The land populated by a dazzle of stripes, spots, claws, fangs and tusks. The sonority of ancient survival squawks the dusk. A distant tickle of marimbas floats through the air for good measure.
Alas, we shall set aside these cinematic clichés and photogenic beasts for a moment. For here and now we seek magic in the microcosm.
This is an ode to the un-sung heroes of Botswana. The critters, creeps and unconventional freaks. Nature’s precious eccentrics whose business often flies or burrows beneath the radar.
For though they lack representation in Disney’s anthropomorphic pageantry, they gleam in intrigue, genius and plain old peculiarity.
Botswana is a land inundated with subtle and complex natural wonders. If you magnify your curiosity and excavate your observational inhibitions: The deeper you dig, the deeper you’ll get. From the highly evolved symbiotic relationship between harvester termites and fungus, to the gut flora of the hippopotamus (studies have shown that baleen whales and hippos descend from a common ancestor, through investigation of a similar fermentation process in their gut flora)
Note to reader: For the sake of posterity I shall avoid further investigating Hippotami gut flora for this article, as the prospect of photographing such biological wonder would perplex even the most dexterous photographer
The Aardvark and the Cucumber
Being called Aardvark is similar to being named Aaron; people tend to call on you first, either by alphabetical disposition or mistake. To keep with tradition, I shall just pocket dial Aardvark and begin.
Aardvark, or ‘Ant Pig’ is a clumsy looking fellow- whether through divine parody or niche species evolution. It endearingly resembles the coupling of an elephant and a rabbit (of which it is both distantly related). The Aardvark nocturnally meanders through the savannah and has evolved to enjoy the burrowing lifestyle. Aardvark digs sandy soils, in search of ants and termites. It has an elongated pig-like snout with a tenacity for sniffing out ants that would give Ozzy Osbourne a run for his money.
Highly evolved claws allow it to burrow at incredible speeds, to the extent to which its main defense mechanisms include ‘burrowing’ and having ‘thick skin’ (nature’s Kevlar against canines). Evolution has basically equipped the Aardvark with ‘hide and seek’ skills and a high pain threshold.
The Aardvark’s tongue sweeps insects directly down its gullet. It has a stomach that acts as a gizzard, which essentially grinds up ants and termites, thus relinquishing the need for teeth. But it has two cumbersome front teeth that seem to pose no practical purpose…
Until you take into consideration the curious relationship between Aardvark and Cucumber.
There exists an endemic subterranean cucumber: Cumis humifructus that fruits about 30cm below the ground’s surface (an incredibly rare, and let’s face it, inefficient reproductive strategy for a vegetable). The cucumber fruit (roughly the size of an orange) has a thick skin and only in rare circumstances is it able to germinate its own seeds.
The relationship between Aardvark and Cucumber is a product of symbiotic co-evolution. This subterranean cucumber is the only vegetable known to be eaten by the Aardvark (which proposes purpose for the ‘cucumbersome’ front teeth). After Aardvark digs and consumes the cucumber, it will collect its manure, then cover its seed filled dung with a layer of soil. Therefore Aardvark not only removes the seeds from the fruit but plants and manures them… Africa’s odd and honorable sub-surface cucumber farmer.
The Cucumis humifructus in Afrikaans is called ‘Erdvarkkomkommer’ translating directly to ‘Aardvark cucumber’, and in San dialect is called !Kung – meaning ‘Aardvark shit’.
Next time you’re on Safari having a Gin and tonic with a fresh slice of cucumber, keep an eye on your cucumber, there are weirdos out there.
Termite Air-conditioning systems
Anyone whoever called Botswana an under-developed country has either never seen the intricate infrastructures of Harvester Termites or has never been to the culturally charismatic town of Kang.
Harvester termites account for more biomass in Botswana than all other mammals combined. These termites are fundamental soil developers. The dry, sandy soils predominantly lack a humus layer. In most ecosystems’ earthworms develop this layer (earthworms seemingly like a bit of humus on their earth worm falafel). In Botswana this role is largely left to harvester termites.
These industrious workers will dig up to 30 meters in sandy soil to locate water aquifers, then tirelessly bring water to the surface in order to regulate temperatures within their homes. They maintain a constancy of between 96 and 99% humidity within the mounds (remember this is the Kalahari Desert, where its drier than British humour).
The termites have developed intricate air conditioning systems, regulating the diffusion of air though semi porous walls. There is only a 1°C internal temperature fluctuation from 30°C throughout the year, compared to the vast external temperature shifts (ranging between 0°C and 45°C).
Interestingly the cooling system of the East Gate Shopping Mall, in Harare was designed on the principles of harvester termite mound climatization. An example of biomimicry and a wonderful ode to ancient insect engineering. It’d be better if it wasn’t for a shopping mall (the pustular head on the carbuncle of human “civilization”) but we as a species are still evolving.
The Termite mounds can reach up to 10 meters in height, which if you are a termite (a humble 25mm) is essentially a super structure. It would equate relatively in human terms to the Shanghai Towers (632m in case you feel like googling it).
A queen termite can live up to 50 years (She is the longest living insects known to man); Freddie Mercury only lived up to 45, long live the Queen! She can produce an egg every 3 seconds for up to 15 years, constantly, that’s a lot, and luckily so because our old friend Aardvark can eat up to a hundred thousand termites a night.
Many of the islands in the Okavango delta are evolved from harvester termite mounds. They lay the foundations conducive to speciation by other organisms, terraforming and birthing islands, with a smaller carbon footprint and far less hullabaloo than projects in Dubai.
The Harvester Termites are Odontotermes Termites, or fungus growing termites. They have this incredible pocket on their hind leg in which they store fungus spores (Termitomyces reticulatus). There exists an exclusive and intricate relationship between harvester termites and this fungus.
They plant and spore fungus gardens within their mounds. The gardens resemble small grey/brown walnuts; the fungi act as an external stomach or digestive system. The termites plant and nurture the gardens, feed the fungus their excrement and then eat the fungus’ excrement. A bit of the old quid pro quo. Perhaps it’s the age-old art of fertilizing the crops. Perhaps it’s permaculture. Perhaps it’s an odd homage to the 2009 classic ‘The human centipede’ who’s to say really.
If the termites are removed the fungus will take over the nest, but they will exist symbiotically if they co-habituate, similar to human children. The termites lick the fungus, while doing so secrete an antibiotic material that prevents the growth of alien fungus in the garden, (similar to human children? I don’t know, I don’t have kids).
There is also a delicious culinary mushroom that grows from these termite mounds in the rainy season, called ‘Termite mound mushroom’, or in Setswana ‘Maboa’. Now ‘Maboa’ with an inflection on the ‘M’ is the word in Setswana for pubic hair, this can lead to awkward situations, when inquiring if someone is serving ‘Maboa’ in a restaurant.
Now dear reader we find ourselves perched on a fugally fecundant, termite mound evolved island in the Okavango Delta.
The sky envelops the earth in a photograph from the 70’s kind of way. The Sun floats like an angry dumpling through cerulean soup, the soup is tepid. Your ears happily tuned into swamp jazz (the only station round here), woodland kingfishers tattooing staccato, the river reeds pedaling an undercurrent legato. The bell frogs chime in as if an overture of cyclist greetings. Occasionally a baritone hippo laughs in French.
Your nose is piqued by dusty winds, redolent with the hidden hint of guava in wild sage. It carries the seductive whisper of rains the river yearns for. The river has carried away the last remnants of the accumulated stupidity of mankind. Breathe deep and relax, you’re on river time now.
The lily-garlanded water is a bubble and blister with life, and in the day’s heat, it is as inviting as iced tea. Tempting, but an ingrained sense of self-preservation tells you, “Hell no!” for this river contains more reptiles than the White house.
Defining Reptilian gender
The Nile crocodile, prevalent resident reptile supreme of the Okavango Delta, lacks sex-determining chromosomes. The gender of adorable baby, flesh-munching crocs is determined by external temperatures during egg incubation. In experiments, eggs incubated between 32-33 degrees Celsius resulted in male offspring; if the temperature is higher or lower it will yield females.
Temperatures generally vary from the top to the bottom of the nest resulting in both genders in a hatch. “A difference in 0.5-1 degree Celsius in incubation experiments resulted in markedly different gender ratios”.
On the positive side: When choosing the colour of gender stereotyping onesies for a reptilian baby shower, you could presumably look through the month’s temperature chart and have a fair whack at being correct.
On the negative: Due to Mankind’s cavalier attitude towards carbon emissions and the tragedy of global warming “Rising temperatures could cause the birth of more females and less males”. Which is serious cause for concern for the posterity of crocodile and lizard populations. And there is no need to ruin the ecosystem just because you want to go for a crocodile free swim.
The Tortoise Bladder
On a lighter note, the Leopard tortoise’s bladder can store 40% of its body weight. Tortoises will wait to urinate until they find more fresh water to “flush and refill the tank”. This is a pretty useful evolutionary tool if you are stuck in the sweltering Botswana summer, far from the Oasis of Kang. Also, a good reason to not pick up a tortoise as they use their urine as a self-defense mechanism. The Uric acids that other animals continually flush out get crystalized by the tortoise. This allows them to flush out only those waste products as a translucent white concentrate, which really stinks. I can say from first-hand experience. I once moved tortoise off the road, and I can never wear those pants again, also the poor thing probably had to walk back to Kang to refill the tank.
Delicious worm snacks
Mopane worms, a staple and a wonder to behold.
Swathes of mopane forest give Botswana its characteristic and enchanting scenery throughout the eastern and northern parts of the country. These Mopane forests glean with iridescent green, come the first rains. During the dry season they carpet the undergrowth with startling umbers, the leaves look like little orangey/red angel wings, these colours contrasting the forever blue expanse of the sky, set a truly endemic landscape.
The leaves of the mopane tree hold a startling 15% protein, being a primary bank of nutrition in a desert. As a defense mechanism the trees protect themselves from foraging animals by producing poisons. High levels of tannins and terpenoids render the leaves inedible to almost all animals….
May I please introduce a little hero: the Mopane Worm. These squishy savants feed exclusively off the leaves of the mopane tree. They are gluttonous gourmands of leaf litter. They look like Jackson Pollock’s’ paintbrush sprouted legs and became a vegan. A psychedelic intestinal tract with limbs. Through their ravenous digestion of leaves they render the Mopane leaves’ nutrition available to other animals by being edible. Pretty to the eye and palatable as pâte. They have an enticing umami, and as of writing this, an unexploited potential as an ingredient on master chef.
The Mopane worm is an integral link in the food chain. It will transform more organic matter into nitrogen fixing compounds and edible proteins than anything else in its ecosystem. In a 6-week period mopane worms will consume more mopane leaf in biomass than elephants in an equal area over a full year (Elephants are another species capable of eating Mopane leaves).
Interestingly an elephant defecates on average 100kg a day. There are over 130,000 elephants in Botswana. Now for the gross total annual elephant excrement weight…
I would do the maths but my abacus lacks the wherewithal, let’s consider it a ‘Shit tonne’-metric. Now considering Mopane worm’s appetite and expenditure, I’m going to guess it’s about a shit tonne and a half. Impressive!
Mopane worms are a delicacy and in season are sold ubiquitously around the country and they make up an 85 million dollar industry across Southern Africa. When travelling in Botswana I highly advise trying them. They are the gooey gem in the culinary crown of Botswana’s entomological offering. The wonderful and talented Chef at the Akacia café in Maun makes a kick ass mopane pizza.
Now hopefully your curiosity is tickled, as these are mere ice shavings off the iceberg of microcosmic wonders. Come visit Botswana, come for the warm climate, warmer people. Come get your mind blown by instagramable animals and the biggest sky in the world. Then come learn how to escape from all that instagrammage damage, come feed your spirit with wonder, your belly with mopane worms, and absorb some of the magic.
That is a fascinating article, thank. I would love to go back one day if there is anybody left alive after this pandemic
The aardvarks are hungry
This article was so engaging, informative and humourous that I would love to submit it to Orion magazine https://orionmagazine.org if you would grant me permission to do so.
Learned so much!