By James Press, EIT, Geotechnical Engineering Associate, Aterra Solutions
Hello, Geo-Institute faithful! I’m very excited to present the first edition of a new column: More Pressing Matters. I’ll be using this forum to report and opine on some less-than-conventional stories and special interest geotechnical topics across a variety of creative formats. It is my goal to produce columns that are some combination of informative and entertaining. Please enjoy the first (and hopefully not last!) edition…
My first assignment on this beat was to conduct an interview with a geotechnical engineering colony operating in my local area.
EDITOR’S NOTE: His assignment was to interview a representative from a geotechnical engineering company in the suburban Philadelphia area. Whether through a typo or selective listening, he arrived at colony all on his own…
And what luck! There happens to be an active colony of workers already operating in my yard! These intrepid and industrious soil engineers have been toiling away at a major infrastructure project all summer. Now, camera tripod set and audio recorder in hand, I’m ready to get down and dirty to ask some hard-hitting journalistic questions.
To kick off the brand-new GI video series, Director’s Cut: The Director’s Cut, I present a Geo-Institute exclusive: an inter-species interview with the colony of ants who’ve made their home underneath the cracks in my concrete sidewalk!
EDITOR’S NOTE: The camera used for this segment was never properly turned on. Also, there is no such ridiculously named video series. James was told to interview one human person and write 500 words max. What we’ve salvaged below is a transcript of the limited audio that did make it back to Corporate.
[AUDIO RECORDING BEGINS ABOUT HALFWAY THROUGH AN EXCESSIVELY LONG INTRODUCTION]
JP: … hoping to catch these worker ants on their lunch break to ask some questions about this ongoing construction project. I’ve been marveling at the worksite from my office window for weeks now and it’s time to find out just what these ants are up to!
[Footsteps can be heard as James approaches the ants and kneels over the sidewalk to get in close.]
JP: Hello, little friends! I’ve got some questions about this hill you’ve been building. I suppose you’ve got the ant-sirs!
[James laughs at his own (terrible) joke.]
JP: All kidding aside - I’ve done a lot of reading on ant construction techniques, and I must say I’m quite impressed! Some literature states that you can move up to 80 pounds of soil in only a couple of days to excavate your tiny roadways and tunnels.1 And it would appear much of that displaced material is stockpiled in the form of mounds, situated at the angle of repose for the fine grains of sand and other little silts and clays you manage to pull above ground. My question for you is this: how do you manage such efficient and organized geotechnical engineering projects without a college degree?
A: [Ants can be heard scurrying back and forth from their nest as the audio recorder is brought close to the anthill. By the sound of it, one of them is carrying a rather large (proportionally) piece of leaf.]
JP: I mean, I’ve heard from some researchers that you possess a superb intuition for tunneling. Whereas we humans compute the complicated geometric stress distributions and impacts of arching effects on our tunnel models long before beginning excavation, you ants can actually identify loose grains that are ripe for movement without disrupting the internal stability of your tunnels.2 You are, in essence, sensing which grains are load bearing and which are not. Some have even compared this to how a human might identify the proper piece to pull from a Jenga tower! Care to comment on this uncanny ability?
A: …
JP: So obviously I’m a little too big to enter the tunnel network that comprises your nest, but I appreciate the invitation! I’ve seen some graphical representations that estimate your colony might be expanding seven feet or more below my sidewalk, which certainly sounds like a lot of ants! And a lot of soil, being carried up to the surface in your tiny mandibles. No offense!
A: …
JP: And while I’ve certainly droned on about the tunnels, I’d be remiss to not mention the important function provided by those mounds of spoils with which you form your anthill! I’ve heard you bring your eggs and larvae up here during the day for all-important solar incubation. And on hot days like this I’m sure they stay plenty warm! How many little ones do you have back home? I mean, um, below my sidewalk. Which is where you all live. So very close to where I live…
A: …
JP: Now I know you’ve probably built countless underground chambers to store your food, rest… and read your Terzaghi textbook!
[The laughter of an odd man who needs to find a hobby can be heard.]
From what I’ve read – based on the size of your ant hill and how long you’ve been digging… I’d estimate your population here as… I don’t know, maybe a quarter of a million ants?
A: [The faintly audible foot(?)steps of several hundred ants marching in and out of their nest can be perceived.]
JP: That is certainly an unsettling number of ants in my front yard! A promising labor force, however, for anyone enterprising enough to negotiate a construction contract with you able-bodied arthropods. In fact…
[James can be heard attempting to offer his business card to one of the ants, who apparently does not accept]
JP: Well, this has been an enlightening experience to say the least. Episode one of a promising new video series, that’s a wrap! And I’ll just turn this camera… wait a second, was this thing on?
References:
1. Building a New Home. Natural World: Ant Attack. BBC Earth.
2. Unearthing real time 3D ant tunneling mechanics. Proceedings of the National Academy of Sciences. August 2021. Macedo, Joya, Ando, Viggiani, Pal, Andrade, and Parker.