With the upcoming release of the "Ant-Man" movie, we decided to talk to the the Department of Entomology's resident ant-man, Dr. Ted Schultz, about his long-time passion for ants. He may not be able to communicate with ants, but his research on fungus-farming ants, both in the field and the department's AntLab, has contributed greatly to our understanding of these fascinating insects!
Q: What made you decide to study entomology, and specifically ants?
A: Ever since I was a kid I have loved animals, especially insects. Like a lot of kids, I liked to catch animals and keep them for pets. At one time or another I had pet box turtles, a pet tree frog, pet lizards, pet salamanders, a hamster, a mouse, a rabbit, even a bat. I also caught insects and kept them in jars. I punched holes in the metal jar lids with a hammer and nail so my bugs could breathe. I experimented with giving them different things to eat. I read as much as I could about them, but I had no adult guidance for any of this except that my Dad helped me make terrariums and cages and my Mom put up with two big box turtles living in a kiddie pool in our dining room. Then one day when I was 7 or 8 years old my Mom gave me a book called The World of Ants and I discovered that ants lived in societies and had behaviors so complicated that they rival those of humans. They have wars, they enslave other ant species, they tend aphid "cattle," they sacrifice their lives to defend their nestmates, and -- the one that impressed me the most -- they grow fungi for food. Some ants are farmers!
Sometime in high school I stopped thinking I was destined to be a "zoologist" and years went by in which I studied art and computer science and worked as a dental technician, printer, cab driver, proofreader, paste-up artist, freelance writer, and editor, among many other things, but I was always reading about insects and especially about social insects and ants. Riding back and forth on buses from San Francisco, where I lived, to a job as a printer in Oakland, I read E.O. Wilson's The Insect Societies and I started to think: "Maybe I should study this!" And then I did and here I am studying fungus-farming ants, the ants I read about in The World of Ants way back when I was eight years old.
Q: What is the AntLab?
A: In 1991 when I was a graduate student at Cornell University, I went off on the OTS (Organization for Tropical Studies) Course in Costa Rica, where I learned to dig up nests of leaf-cutter ants, which are a kind of fungus-farming ant. Then, in 1992, I went on a four-month trip to Costa Rica, Nicaragua, and Brazil, during which I dug up dozens of nests of "lower" fungus-farming ants. Like leaf-cutting ants, lower fungus-farming ants also grow fungus gardens, but unlike leaf-cutters they are small, inconspicuous, and generally hard to find. But leaf-cutting ants evolved from lower fungus-farming ants and the key to understanding the evolution of agriculture in ants lies in understanding lower fungus-farming ants. I returned to my advisor's lab with dozens of live colonies of lower and higher fungus-farming ants and proceeded to take care of them, just like I took care of lots of animal pets when I was a kid. I've been doing it ever since. Currently we have over 150 fungus-farming ant colonies in the lab. I could never take care of all of those by myself but, fortunately, I have the help of an extremely capable Museum Specialist, Eugenia Okonski. And the AntLab has grown to include interns, undergraduate students, graduate students, postdocs, technicians, and visiting scientists. Currently, we have a dozen people in the lab, all of whom love ants.
Q: How do you excavate an ant nest?
A: First you need to find it. For lower fungus-farming ants this can take hours or days. You put down a bait (we use Cream of Rice cereal), then you watch ants that walk off with it. When the ant you're looking for takes the bait, you follow it home. Sometimes this can take hours because the little worker ants do not exactly follow a straight path back to the nest and fungus-farming ants are kind of slow walkers. Finally you may see the worker disappear down a tiny, nondescript hole in the ground and you've done it. You've located the nest entrance! You mark it and, if you are not familiar with the nest architecture of that species, you start digging a trench about one meter away from the entrance and about a meter deep. Then you start removing soil from the edge of the trench toward the nest entrance. The closer you get to the entrance, the more carefully you shave away the soil. If you're lucky, eventually you will break into a fungus garden chamber filled with fungus garden, worker ants, baby ants (larvae), and maybe even the queen. You are the first person in the world ever to see that garden. Depending on the species, the entire chamber might only be a few centimeters in diameter. Often there are multiple chambers so, once you've collected the contents of that chamber, you need to keep shaving soil. If you're lucky, eventually you will get the queen and then you can take care of the colony and bring it back to the lab.
Q: Where is your favorite place to do fieldwork and why?
A: Brazil, which is a big country, but almost anywhere in Brazil: Amazonian rain forest, Atlantic Forest, southern forest, and, especially, the Cerrado, which is the Brasilian savannah. I love Brazil: the people, the food, the vastness, the beauty, and the many varied habitats. The Brasilian Cerrado is an ecosystem -- a number of ecosystems, actually -- on par with the Amazon. A tremendous amount of organismal evolution took place in Cerrado and today's Cerrado is a biodiversity hotspot. Unfortunately, it is more endangered than Amazonian rain forest. In 1992 on my first trip to Brazil, I walked into the Cerrado near Brasilia, the capital of Brazil. I remember standing there looking off to the horizon, scanning a seemingly endless expanse of scrubby bushes, occasional small trees, and termite mounds, all under a huge blue sky, and feeling like I could walk off into that landscape and keep walking forever. There are still places where you could almost do that, although in other places you would quickly stumble across soybeans or sugar plantations, or maybe run into a cow. Anyway, there are many fungus-farming ant species in the Cerrado. Jeffrey Sosa-Calvo, my graduate student, and colleagues recently described a new genus of fungus-farming ant from the Cerrado. Lots of important events in fungus-farming ant evolution happened in the Cerrado rather than, as we have always assumed, in the Amazon.
Q: Any new research you are excited about?
A: Lots of stuff. We are using new genomic methods to more accurately reconstruct the phylogenies (evolutionary histories) of fungus-farming ants and the fungi that they cultivate. We now have whole genomes of multiple fungus-farming ants and we are starting to get genomes for their fungi. Maybe something in the genes of the ants and in the genes of their fungi will tell us something critical about how these two partners discovered one another 50 million years ago and how they have co-evolved and changed in various lineages since that time. What we learn might even help humans get better at managing their own agricultural challenges.
Q: Are you a fan of the Ant Man comic?
A: This is going to date me, but I was around when Marvel Comics began. I owned the first issues of Spider-Man, Fantastic Four, X-Men, etc. I read the story "The Man in the Ant Hill" in Tales to Astonish #27 (January 1962), which introduced Dr. Henry Pym, who would later reappear as Ant-Man. Marvel Comics supplied my entire childhood mythology, my pantheon. I am absolutely thrilled that, finally, movie technology has achieved the state necessary for capturing the essence of those comics on the screen. And I am doubly thrilled that an Ant-Man movie is appearing this summer!
Q: If you could be any insect, alive or extinct, what would you be?
A: As much as I love them, I am not sure I'd want to be an insect, but, if I had to choose, I would want to be the very first fungus-farming ant species, which we know lived around 50 million years ago somewhere in South America. The reason I choose that ant is because I would really, really like to know how the first fungus-farming ant discovered agriculture.
To learn more about Dr. Schultz's research, please visit his page on our department website.
Ted Schultz, Jessica Bird, & Erin Kolski, Department of Entomology, National Museum of Natural History, Smithsonian Institution, Washington, DC, USA.