The real masters of the planet are underfoot

kw: book reviews, nonfiction, natural history, termites, technology

This interesting aerial view in northeastern Brazil is a portion of an area the size of England all covered with this kind of patterned landscape. The bumps are termite mounds; there are millions of them, each about 30' (9m) wide and 8' (2.5m) tall. They have had their ages measured: between 700 and nearly 4,000 years. This is just one major area occupied by just one termite species. The area of Britain is 122,000 square miles. The amount of the earth's surface that we humans have covered with roads and buildings and other infrastructure comes to 2 million square miles.

It is safe to say that our "underground footprint" is smaller than our surface works. Not so for termites. Even mound-building termites have substantial subsurface workings. Of course, mound-builders are not the subterranean termites that plague suburban homeowners in the US. Their nests around here are entirely below ground, plus inside the wood of our buildings and of dead and fallen trees. Mound-building termites gather grass or other plant material and return it to the mound, where they either digest it directly or use it to make compost to grow a fungus that they consume.

Here is another view, of an area in Australia, populated with termite mounds, of a different genus and species from those in Brazil. These can be 15' (4.5m) tall.

There are about 2,000 species of termites. Added together, the world's termites weigh ten times as much as the entire human population. For all that, termites are little critters. Typically half the length of a grain of rice, they are similar in size to the little "sugar ants" and "grease ants" that might invade your kitchen (not the big carpenter ants that occasionally come indoors).

This is what Eastern Subterranean Termites (Reticulitermes flavipes) look like, magnified about 10x. The big soldier (with the orange head) is 5mm long, and the workers are mostly 3mm long, although you can see at least one extra-small worker that is no more than 1.5mm long. This image is by Gary Alpert of Harvard University, and is licensed under a Creative Commons Attribution-Noncommercial 3.0 License; see more images at bugwood.org.

Termite are practically ubiquitous, living nearly everywhere except in areas of permafrost. Lisa Margonelli became interested, then fascinated, then obsessed with termites. In particular, she wanted to know what the latest termite research had to say. As she writes in Underbug: An Obsessive Tale of Termites and Technology, most termite research, being funding-driven, is focused in two areas. Firstly, knowing that termites can digest wood, scientists want to know how it is done, with the goal of replicating the feat to make woody and grassy plant matter into fuel. The general term has morphed from "biofuel" to "grassoline". Secondly, termites and their mound-building skills are studied to inform the technology of swarming robots. It has been calculated that the amount of neural matter in a large termite nest or mound is comparable to the brain of a Labrador Retriever. Can multitudes of nearly brainless critters carry on a kind of collective cognition? We are not talking self-awareness here, just calculating power.

Now, guess who funds the latter effort the most. The Military. Midway through the book, a researcher opines that if millions or even billions of tiny, flying robots can be 3D printed for $1 each, and each can carry a tiny shaped charge weighing 1g, capable of piercing the human skull, they might be able to wipe out an entire army without any of "our" folks coming in harm's way. It occurred to me that it might take a rather sophisticated CPU to be able to reliably recognize foe and friend. And now that we're at the limits of Moore's Law for single CPU power, it's unlikely that a robot "brain" lighter than a small cell phone's motherboard could do the trick, now or years into the future. To make such a 'bot fly, you'd need wings large enough that it would be the size of a seagull rather than a big wasp. It's hard for a seagull to sneak up behind someone so as to crack their skull. But then, if it is that big, you could give it a bigger bomb.

Ms Margonelli spent nearly ten years visiting and working alongside scientists in Namibia, Australia, South America, and a few places in the US, being instructed tirelessly by them as she struggled to grasp the concepts. In this image the bent-over witch's hat shape is not random. The angle and its direction optimize the mix of sun and wind exposure. Though one theory has such tall mounds acting like chimneys to facilitate the flow of gas and vapor, the research she witnessed did not bear that out. It is still a mystery, but millions of mounds throughout Namibia have the same shape and orientation. The more vertical mounds in Australia (second picture above) must operate differently, perhaps partly because they are at a different latitude.

So far, grassoline cannot be efficiently produced. The metabolic pathway for digesting cellulose and lignin includes a huge assist from bacteria and protozoa in a termite's gut. There are a great many steps, and yields are low. Consider: If you can only produce a gallon of liquid fuel by also producing 100 gallons of unusable waste—stuff nothing will eat and that can't be burned—is that worth it? In recent years, Americans consumed on average a little more than one gallon of gasoline per day, each. Nearly 400 million gallons daily, more than 110 billion gallons yearly. What do you do with 1.1 trillion tons of waste? In addition to what we already produce…

No matter what we do with termite research, rampantly increasing pollution of all kinds, including "heat pollution" caused by greenhouse warming, will make the future less pleasant than the present. Will we be driven back to a new "stone age"?  That is quite unlikely, but there are certain to be disruptions. One side finding from all the termite research is that the land above termite workings is more fertile and grows more vegetation. The little critters may have a hand in saving the planet for us, for they work steadily to make it better for themselves, with too little brain to indulge in politics.