Daily Archives: July 6, 2008

Empire of the Ants

While sitting on a bench reading a book as I waited for the bus the other day, my attention kept being drawn to the ants on the ground that were hectically going about their business of foraging for food and whatnot. Insects have always deeply fascinated me, especially the highly organized species that parallel human societies such as bees, wasps, termites, and most especially ants. As a kid, “ant watching” provided untold hours of entertainment, and sometimes even, I have to confess, the sort of cruel amusements now more usually worked out in computer simulations and various so-called “god games” like Populous.

As I was fixed on the ants’ busy traffic across the cement pad of the bus shelter, it struck me just how amazing fast they travel relative to their tiny size and I wondered what this might translate to in human terms. It’s commonly known of course that ants perform amazing feats of strength, carrying up to twenty times their own weight if necessary; something that to us that would be like lifting a small car and then carrying it over considerable distances without even breaking a sweat. Their rate of locomotion however is less well known.

In fact, this question turns out to be surprisingly difficult to answer because of all the different factors involved such as: the size of the ant; the type of surface it’s moving across; whether there is an incline or decline involved; whether the ant is laden or unladed; the atmospheric temperature; the type of activity the ant is engaged in; and so on. One figure mentioned with quite categorical certainty by some “expert” was 2 mph (3.2 kmh). That’s quite possibly wrong for all of the reasons stated above, but it seems plausible enough. Given the average walking speed for people is approx. 3.2 mph (5.2 kmh), if we were to perform a direct comparison by simply extrapolating the ant’s rate of locomotion into human terms according to size alone, it would be like moving twice as fast as a Lamborghini!

Now, while this kind of idle speculation may be good for distracting the mind of bored commuters, it’s actually complete bunk because things just don’t work this way in nature. Ants are no more super fast than they are super strong. The reason ants can perform what might seem like remarkable feats of strength and speed in human terms has everything to with their small size — it’s all a matter of simple geometry and the characteristics of muscles. As any object grows in size its volume and weight increase much faster than its height, whereas the strength of muscles can only increase by the square of an animal’s height (a good explanation of this phenomenon can be found here).

Anyway, long story short… While attempting to determine the average speed of ants, I stumbled across the following video excerpt from the documentary Ants — Nature’s Secret Power about ant colonies that really is complete astonishing. In it, a group of scientists fill a grass cutter ant hill with 10 tons of concrete (that fact alone is extraordinary). After it dries they spend weeks excavating the site to reveal the underground ant “megalopolis” — a sprawling network of subterranean highways connecting the various chambers that comprise the complex architecture of the ants’ “city state” as its described in the film. Absolutely fascinating.

It’s estimated that an ant brain has about 250,000 brain cells. By comparison, a human brain has 10,000 million, so it may be said that a colony of 40,000 ants has collectively the same size “brain” as a human. Some colonies however can grow to the size of several hundred thousand ants, thereby giving it a rather extraordinary collective “brain” compared to that of a single human. Perhaps Mark Twain was right after all when he said that in certain “high mental qualities” the humble ant “is above the reach of any man, savage or civilized.”

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