Hitting Pay Dirt – Under the Scope

Earlier this spring, I was up in the middle part of the state at a conference on the LSU-Alexandria campus. After a long, caffeinated day of listening to scientists and their students from around the state discuss new findings from their laboratory and field work, I walked out of the classroom building into the cool, fresh air that early morning rainstorms had pulled across the CenLa prairie. Fresh air is just one of the things you miss when you’re held captive by work inside a building all day long. Another thing is the lingering and refreshing smell of rain, which those people inside the building that day might describe as the combined scents of ozone, geosmin, and a touch of 2-isopropyl-3-methoxypyrazine.

Sniffing fresh air and the scent of rain weren’t the only alfresco moments I admired that day in Alex. Historical campus trees wearing their perennial shaggy dresses of moss were now also draped in shawls of newly sprouted green leaves. Birds newly emerged from their hiding places chattered incessantly with one another, sharing boastful stories of their morning storm survival and complaining about uncomfortably wet feathers. Weedless campus lawns manicured perfectly to a flat and continuous height rose just above the level of sidewalk pavement. And though it was just a moment and a glimpse, I could swear that cricket crossing my path along the sidewalk was wearing a tuxedo with top hat and cane.

But aside from that crooning little six-legged star-wishing Disney illusion, it was a different type of insect that really captured my attention. As I admired the impeccable university lawn, my brain was helpless to discover an imperfection. And I mean helpless. After all, finding imperfections is what scientists do—like noticing an apple falling from a tree, or mold inhibiting bacterial growth, or rings around a spherical planet, or a fracture in the earth’s crust, or the meander of a river, or a doomed cicada with unfurled wings, or a skipped heartbeat, or a skin tag, or a fungal toenail. Those things that disrupt beauty and symmetry and order in the universe are what scientists immediately recognize, especially when they’re caffeinated. I was familiar with this type of lawn blemish because they occur in my own backyard back in PoV country. Nonetheless, something was peculiar about this Alexandrian one.

The lawn imperfection was an anthill, and the anthill dirt was red.

Now, I’ve played in dirt as a kid. I have inadvertently ingested dirt after being tackled and forcefully pressed into a football field behind the line of scrimmage. I have excavated holes in all the backyards where I’ve lived to bury artefacts that future archaeologists might find interesting, like that old G.I Joe doll with the missing right arm. So, I have seen dirt up close and personal, and it’s always flat brown or shiny gray-black and never the reddish color of candy apples, which, incidentally, is a preferred food for mound-building ants.

The observation that Alexandrian ants make red anthills makes perfect sense, just like the rest of the universe eventually does to a scientist–as well as to normal people, especially caffeinated ones. Alexandria was built on the banks of the Red River, and all the land around where I stood that day had been deposited in prehistoric times by red sediments that settled from river floods. Now, an uninitiated, headlines-reading conspiracist might suspect that the red color was caused by food manufacturers north of Louisiana dumping barrels of recently outlawed red food dye into bodies of water after their state governments had banned its use. But, no.

The red in the Red River actually comes from rust. Once upon a time, a huge prehistoric puddle of red clay and red sandstone grew in the center of North America, just east of the Rocky Mountains. Particles of that clay and sand were surrounded by iron ore dust from within the earth’s crust. And, just like that spot on the hood of my car, iron exposed to oxygen over time becomes oxidized: It becomes iron oxide, which is rust and which is reddish. And the Red River has been painting the town red, carving its way through that big rusty puddle, ever since.

When an Alexandrian ant colony mines the earth and carries rusty dirt to the surface, those ants expose an important mineral. After all, iron is not only used to make buildings and vehicles, and machines, but it is also essential to our bodies, enabling red blood cells carry oxygen, for instance. The significance of this red dirt made me wonder, as a scientist is helpless to do (and I mean helpless): Could Alexandrian ants, which have chewed and excavated this beautiful red stuff, actually tell that the dirt tasted like rust? So, being a scientist, I knelt on the lawn to get closer to the mound and scoop up a bit with my hand to taste it myself and then conclusively know whether or not ants could taste the rust. Yes, some scientists get so carried away by their wonder that they’re willing to participate in their own experiments—like eating dirt after ants have chewed it. But I’m not that kind. I knelt down just to take a closer look.

The helpless wonder didn’t stop there, however. Observation of a red ant hill on land in the basin of the Red River made me think: Do ants in Yellowstone National Park make yellow mounds? What colors are mounds in Orange County, California, or the Black Hills of South Dakota, or Greenville, South Carolina? And what about the local ant hills around Bayou Blue? Do all ants around the world chew up and raise colorful and valuable metal ores from underground? The answer to that important question is currently under investigation, as I conduct an environmental study that promises to be very lucrative. If you’re looking for me, you can find me these days with a shovel and a bucket or two kneeling on someone’s lawn in the town of Golden Meadow.