The Mystery of the Italian Ants*

[the following is a guest post by Rob Dunn]

A few weeks ago I went to elementary school in Italy. I had been asked to visit one of the schools where professors at the University of Parma have been working with children to study ants.

There were three of us on the expedition. The other two were my six-year-old daughter and Fiorenza Spotti. Fiorenza helps to lead the Parma ant group’s work with schools. When we entered the classroom, Fiorenza introduced my daughter to the students. Seconds later, my daughter was enveloped into a sea of little Italian girls eager to hold her hands. Fiorenza then began to ask the kids questions. “How do you tell the difference between an ant and a wasp? Are the worker ants girls or boys?” And then, “What kinds of ants do you think we will find?” I expected the students to say “big” or “stinging,” but Fiorenza had already visited this class and prepared them for what they might find. A proud little boy with hair that stuck straight out in every direction remembered the visit. His hand shot up. Fiorenza called on him and he squeaked, “Lasius emarginatus,” and then, as if awaiting a badge, beamed.

The project Fiorenza is leading with the kids is a version of a project we began several years ago in the U.S., a project we call School of Ants that aims to engage children and adults in studying ants and, in the process, to conduct rigorous science about the world with us. The project has spread across the U.S., Australia and, now, thanks to Fiorenza and her advisors, Cristina Castracani and Alessandra Mori, Italy.

In the U.S., participants in the project put out crumbled Pecan Sandies cookies to attract ants in both green and paved areas (which they, and we, can then compare). Using Pecan Sandies as bait for ants is a time honored tradition among ant biologists. The cookies may not be very healthy for humans, but to ants they are a super food—sugary, salty and fatty all at once. In Italy, things proceeded similarly. Each child was given a sampling vial, a flag to place beside it (on which they would scribble their name) and the instruction to go forth to sample either a cement or green space in their schoolyard. Everything was just as we do in the U.S. (see video) albeit with more style. The flags the students used to mark their spots were set in little wax bottoms, each one decorated uniquely and the Pecan Sandies were replaced by cookies Fiorenza’s mom made, cookies so good that fewer than half of them seem to have made it out of the lab. With glitter and small vials of delicious cookies, the students went, teeming, bumbling, squealing and running, outside, where they would forage, like ants, for ants. They were like Lewis and Clark, or at least what Lewis and Clark would have been like if they had been asked to explore the West when they were eight.

The “yard” at this particular school was a large cement play area with a few trees in pots. It was a good place to kick a ball around and run in circles and giggle and shout riotously, but I was curious about what could be discovered in the way of wild species. It was not, by even an ambitious stretch of the imagination, a very wild sort of nature, but it might be enough to entice children to study ants and pay attention to nature. That is what I hoped Fiorenza could do in this cement area, but what would she and the students really find?

At home, I would be able to tell you. At home, in Raleigh, North Carolina, such a patch of human industry, for example the cement pad behind my daughter’s school, Fred Olds Elementary, would probably have some pavement ants (Tetramorium caespitum) and maybe a species or two of what are sometimes called cornfield ants (species of the genus Lasius). What about in Italy, where so much is different? Perhaps something very unique! I was excited, eager even, to see what could be found among the urban, Mediterranean, European ants, in a region where cities have existed for several thousand years. The vials were set out, mostly with care, and the students went back inside to wait, visions of ants dancing in their heads.

An hour later, the students returned to gather the ants and found three species. There was a species of Monomorium I had never seen before, a species of cornfield ant (Lasius emarginatus) and, lo and behold, the pavement ant, Tetramorium caespitum, exactly the same species that runs this way and that behind my daughter’s school. I came to Italy to find unusual new ants and found the ants I am mostly likely to see at home!

cornfield ant

While the students went back inside to talk about what they had found and then, I assume, it being Parma, eat pasta and/or pizza for lunch, I was left with my daughter and Fiorenza to consider why it is that exactly the same species is common both in Raleigh, North Carolina, and in Parma, Italy. I have my ideas (It isn’t hard to imagine that the Nina, the Pinta, and the Santa Maria were joined in their travels to the New World not just by rats, chickens and syphilis, but also by an ant queen or two), but in the meantime I thought to ask my daughter what she thought of the Italian school. She listed some things that were different (everyone spoke Italian, there were pitchers of water on the tables in the lunch room, the teachers let the students sit on the tables), “but mostly it was the same, they even had the same ants.”

“They had the same ants,” is the sort of thing that only an ant biologist’s daughter says. It is funny, but it is also, I think, laden with deeper significance. There is hope and mystery in the similarity of our ants.

Before I go on, I have to clear up an issue of names, an issue that seems semantic, but hides additional mystery. The pavement ant used to be called Tetramorium caespitum but when it was studied genetically several years ago it was discovered that across Europe and parts of Asia what had been called “pavement ants,” T. caespitum, were actually several different species. These species are difficult for scientists to tell apart and so had been treated as though they were one and the same. One of these species is the real Tetramorium caespitum and the others are now in need of scientific names. They are temporarily called species A, B, C, D, and E. They might not have anything more closely resembling a name for a while and so the species that was found in Parma and that is common in Raleigh (and that is also the most common ant, for example, in Manhattan) is, simply, E.1

Tetramorium sp. E appears to have been introduced to the U.S. from somewhere in the Mediterranean. It is, interestingly, one of the species that occurs in Genoa where Columbus grew up. It also occurs in the Fertile Crescent, where wheat, barley, asparagus and even hamsters were first domesticated. Basic attributes about Tetramorium sp. E seem to still be poorly known. Does it have one queen or many? What does it eat? What other species live with it? Or my favorite, why does it thrive in cities, even when other ant species fail to? Not only does it thrive in cities, it is a specialist at living under cement. But why? The second graders and my daughter thought it might find more protection under the cement. It might, they said, “avoid stomping feet.” “Maybe it likes to eat the food the kids drop on the ground!” These were all interesting explanations of the benefits of living under cement, but could not explain why so few other species seem to be able to do so with such aplomb2.

The inimitable Species E

Most ants have mysteries. Most species have mysteries. For goodness sake, the majority of species on Earth don’t even have as much of a name as Tetramorium sp. E and yet this is not just any species. It is an incredibly common species. It is probably found in schoolyards across the Middle East, Europe and eastern United States. So far it has been one of the three most common species recorded by participants in the School of Ants project in the U.S., across the thirty states where kids and adults have so far participated. Children have been watching this ant carry away their food for generations. The Romans probably watched Tetramorium species E in Parma and elsewhere in Europe two thousand years ago, and the Etruscans before them. These ants have been seen again and again, most conspicuously when they wage wars on the cement and hard-packed ground. They probably did battle in the coliseums, beneath the gladiators, waving their mandibles like swords. Whether or not it has a name, you have probably seen this ant. This is precisely the kind of ant children can make new discoveries about. It is precisely the kind of ant that might reward your patience and observations not just with interested behaviors but also new scientific insights. It is the kind of species that I hope the School of Ants can help us understand.

Typically, one would see the similarity of species in different regions as a piece of a global ecological problem. It is part of the global homogenization of species around the world due to the spread of human-associated plants, animals and even microbes. Such spread makes the unique and lovely differences among places fewer. But, given that it has happened, given it is a reality for the pavement ants – but also the pigeons, rats, roaches, isopods, earwigs and many plants – of our cities, it is time to take it as an opportunity. If we could understand the stories of these species and tell their stories – again and again – we could tell them to children around the world. We could use these species and their stories as a way into nature, a way to all the benefits that nature provides, some of which might be provided even in cement schoolyards in Italy, Australia, the United States, or beyond.

I am getting carried away. Pavement ants will not fix all that ails you. If your relationship stinks they won’t make it better (if they cause you to ignore your partner because you are always looking down, they might make it worse). But maybe they can help to lure kids outside to study the nature around them and then maybe, lure them further down the trail to even more remote nature. It is a start, a possibility.

All around the world, no matter how urban and devoid of what we usually call nature, there are ants. They make trails that lead both back to the queen and out into wilds. I hope that the School of Ants turns children onto these trails and leads them into the richness of life. It is only a beginning, but sometimes the first challenge is to point out the path. When confronted with a fork in the road, may our children always choose the one the ants have chosen, through the weeds.

Meanwhile, my daughter will go home to a life in Raleigh soon that is different in many ways from the one she has lived while staying in Italy and elsewhere in Europe. Yet, she can know that when she sits on the cement behind her school and watches the pavement ants gather food, that her new friends in Italy might be doing the same. Although, as my daughter pointed out—“in Italy the ants are probably gathering better food.”

*Title suggested by a certain six-year-old fan of mysteries.

[1] B.C. Schlick-Steiner et al. / Molecular Phylogenetics and Evolution 40 (2006) 259–273

[2] I wanted to offer some ideas here, but I don’t really have good ones, though I am fascinated about what the explanation might be, so feel free to offer yours.

14 thoughts on “The Mystery of the Italian Ants*”

  1. Wow, such an awesome post! Assuming pavement is warmer(relative to other nesting areas), it is possible that these ants prefer warmer substrates?

  2. Excellent read (:
    Would laboratory rearing of colonies from different species under different environmental parameters be a way of identifying the things T. caespitum are particularly good at coping with compared to other ants? Then you could start finding the proximate cause of their success.
    Would be a very ambitious project though…

  3. I love it, just as I always love a good story. Thanks Rob, for your poetic wax, and getting carried away.

    Like you say, there are many stories for every species; all that is needed are more good story tellers.

  4. I’ve had similar thoughts but could never have expressed them so eloquently. This is the first post I’ve read but I’ll be coming back to learn more about ants and their friends.

  5. Tetramorium sp. E used to engage in their epic battles on the kitchen floor when I was a child. My parents would freak out and grab the insect spray. Workers would also bite me on the back of the neck when I played on the floor. A tasty morsel for the colony! I was privileged to collect Tetramorium workers from the family home for the 2006 Schick-Steiner, et al, paper that documented the existence of T. sp. E.

  6. Pingback: The Mystery of the Italian Ants « Sociobiology and Behavioural Ecology of Social Insects Research Unit

  7. Mariangela Rollo

    Hello Mr. Dunn,
    I’m the mother of one of those pupils of the Italian school in Parma, who participated to the lab School of Ants, and today we doubled this fantastic experence at the University of Parma, my two children have been invited to the lab with Fiorenza and Cristina (very nice teachers).
    They enjoyed watching the ants at the microscope, draw and colour… and make different parts of the ant. I enjoyed it too.
    Unfortunately, bad weather ruined the outdoor activities, but it was a very nice initiative. My child Alessio (7 years old) loves science and maths.
    Best regards

  8. Pingback: ‘antastic’ resources | Natural Newstead

  9. Pingback: Are British and Irish school-children regimented? | the

  10. Pingback: Why are British and Irish school-children regimented? | the

Leave a Reply