Learning about complexity from termites

This has to be one of the most amazing videos ever made by David Attenbourough, how termites build their homes. As Attenborough explains, their mounds:

have, to perfection, all the qualities you would want from a home; security, heating, air conditioning, and self-contained nurseries, gardens, and sanitation systems.

This is a great mystery to us, and we still do not understand how they manage such an incredible accomplishment:

The spires and turrets are a key element in the air conditioning system in a near perfect mansion that has stout walls to protect the inhabitants from the elements and their enemies, the dungeons where they can gather moisture, barns inside where they can store food and gardens where they can grow their crops. And yet all of this was built by tiny insects with minute brains working in total co-operation in the complete darkness.

Be amazed!

Here is my transcript from the video:

The most impressive animal homes are built by the smallest labourers, termites.

They have, to perfection, all the qualities you would want from a home; security, heating, air conditioning, and self-contained nurseries, gardens, and sanitation systems.

One kind of termite species in northern Australia build a certain kind of home. It has a broad flank but a very narrow edge. The flank catches the full strength of the early morning sun so it is almost painful to touch, but on the other side it is quite cool. They are orientated north-south, because of heat. They do not like the cold, but are easily overheated. They avoid both these disasters. In the morning they move to the eastern side to warm up, but at noon when there is a danger of over-heating from the mid-day sun, only the knife-edge along the top catches the sun.

Most termites retreat underground where the conditions are stable, but because these termites live in an area that floods, only this shape of building prevents them from over-heating, freezing or dying.

The ultimate in termite architecture is in west africa. The biggest, most complex and subtly sophisticated of all their building, a 50ft tower built by Nigerian termites.

There is along, empty chimney. The inhabitants are found much further into the nest. The builders are continually constructing arches, vaults and corridors. Among them are bigger soldiers with muscles needed to power their jaws. Each worker places its pellet of mud in a position demanded by a master plan, but how they do this we don’t even begin to understand. They store their food, wood, in special chambers. It is very hard to digest, but they make the most of it by eating it, and then cultivating a fungus on their dung, which extracts more of the nutrient. They then eat the fungus. The fungus nowhere else but inside the termite mound where the temperature is exactly right for it.

In the heart of the fortress lives the queen. She produces 1000 eggs per day to provide fresh recruits for the gardeners and masons and the ranks of the army. She resides in a special chamber which the workers renovate and adapt to accomodate her growing bulk. After a year or two she is in effect a prisoner. She could not move even if she wanted to, but is assisted by nurses and workers.

There are 1.5 million insects in this colony, and they are their gardens generate a lot of heat. Within the enclosed colony the air could easily become foul and hot. The fungus, and therefore the colony would die if the temperature varies by more than 2 degrees from 31 degrees centigrade.

The colony has a solution and its an architectural one. The cellar is 6 ft below the earth. Its floor has shafts which go down 12 or 14 feet down to the water table where the worker termites can carry up moist mud to carry on their building. The ceiling has a great plate which carries the entire weight of the colony. On the underside is the most remarkable animal structure ever seen. Lines of concentric veins. They are made of mud and they absorb moisture from the colony above. As it evaporates it leaves an encrustation of white salt, but more importantly, as it evapourates, it cools, so the cellar is much the coolest part of the colony. Its this that drives the air conditioning.

The air continuously heated by all the activity in the middle of the building rises up into the upper storeys, but the basement, thanks to the veins, is many degrees colder and it draws down the stale warm air from the colony above down long chimneys which go right down along the edge of the cellar. As it does so there is a seepage of gas through porous dimples in the walls. Oxygen flows in and carbon dioxide out so the mixture approximates to fresh air.

The spires and turrets are a key element in the air conditioning system in a near perfect mansion that has stout walls to protect the inhabitants from the elements and their enemies, the dungeons where they can gather moisture, barns inside where they can store food and gardens where they can grow their crops. And yet all of this was built by tiny insects with minute brains working in total co-operation in the complete darkness.

We might like to think that we are the most accomplished architects the world has ever seen, but if this was built in human terms, with every termite worker the size of me then it would stand a mile high and we haven’t done that yet.

Suggested reading

Signs of Life – How Complexity Pervades Biology, Richard Solé and Brian Goodwin
How the Leopard Changed Its Spots – The Evolution of Complexity. Brian Goodwin. London, 1994
Order out of Chaos, Ilya Prigogine and Isabelle Stengers, 1984

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