Armadillo archaeological mayhem

Reconstructing history rewritten by rodent burrows is a dirty job. But someone will do it

By Andrew Leonard
Published October 17, 2008 7:57PM (EDT)

What do pocket gophers have that armadillos don't? Among the many interesting nuggets of information to be mined from "The Role of Armadillos in the Movement of Archaeological Materials: An Experimental Approach," is the alarming news that "despite its regional ubiquity and notable burrowing behavior," the armadillo "has received little attention in the archaeological literature." The pocket gopher, however, has been "well-studied."

Shame. Shame, I say. Armadillos are way cooler than pocket gophers, and deserve the according academic respect.

On Oct. 2, the organization Improbable Research bestowed its annual "Ig Nobel Prizes" honoring achievements that "first make people laugh, and then make them think." The spotlight shone on the ground-breaking armadillo archaeology findings of Brazilian researchers Astolfo G. Mello Araujo and Jose Carlos Marcelino, first published in the journal Geoarchaeology in 2003, would have been just one of the many, many important developments in the world that escaped my attention during the last month of extreme bailout fun in Washington and New York, if it were not for the great Chris Blattman blog.

The problem: Bioturbation, whether by ants, termites, earthworms, or rodents, disrupts the distribution of items in archaeological sites, thus complicating efforts to piece together what humans were up to so very long ago. The 20 armadillo species indigenous to the New World are particularly industrious burrowers, but good data on exactly how their tireless digging might reposition shards of pottery or some such is in short supply.

Until now. Or 2003, as the case may be. In a tribute to scientific curiosity, Araujo and Marcelino created an experimental site in which they placed hundreds of fragments of ceramic material in layers of dirt and then took careful notes after letting a yellow armadillo (Euphractus sexcintus) loose in the test plot for 53 days, to burrow to her heart's content.

As they expected, "burrow and mound maintenance was clearly responsible for considerable horizontal displacement of pieces."

Some of our findings have never been reported in the literature, such as the fact that armadillos can translocate artifacts downward to great depths as well as expel them towards the surface.

However -- a troubling observation: "Armadillos are responsible for vertical movement of archaeological materials, but the displacement of artifacts does not appear to be systematic."

In other words, armadillos make a big mess that isn't easy to straighten out. Kind of like investment bankers specializing in mortgage-backed securities, if you think about it.

More research, as they say, is necessary. Do the underground meanderings of giant armadillos, (Priodontes maximus) result in different patterns of bioturbation than that practiced by the wide-ranging nine-banded armadillo (Dasypus novemcinctus)? How is our understanding of pre-Colombian human behavior in South America altered by centuries of indiscriminate burrowing? And finally, what nefarious force has directed such disproportionate research attention to the insidious pocket gopher?

The more I learn, the more I need to know.

Andrew Leonard

Andrew Leonard is a staff writer at Salon. On Twitter, @koxinga21.

MORE FROM Andrew LeonardFOLLOW koxinga21LIKE Andrew Leonard

Related Topics ------------------------------------------

Archaeology Globalization How The World Works