Evolutionary biologist Anna Himler, working on post-doctorate
research at the UA, was surprised when her study on the Mycocepurus
smithii ants became part of a discussion on feminist blogs, like
bust.com. The study is about an ant
species that only produces females—reproducing without males.
Himler’s study, however, isn’t a feminist manifesto; instead, it’s a
cool discovery about a group of ants that happen to be farmers. When
Himler came across the ants during field work in Latin America, the
farming aspect is what made her excited about them at first. To read a
bit on Himler’s study, visit news.bbc.co.uk/2/hi/science/nature/7998931.stm.
What did you think about your study being discussed on different
feminist blogs?
Some of the coverage was just untrue. There was some suggestion that
this was a study to look at how these ants are relevant to us as a
sexual species, but it wasn’t. And I wasn’t suggesting that males are
superfluous or becoming obsolete. … One blog also said that these
ants created elaborate agriculture because of or after having no males.
That’s incorrect. These ants evolved to be farming ants first, then
evolved to become asexual. All the other farming ant species are
sexual, meaning the queens produce males and new queens that mate
during reproductive seasons. On the flip side of all this, I was
thinking, “Wow, people really do care about this stuff,” and it’s neat
to try to communicate what is important and exciting about this work to
the public.
Ants are cool. Have you always had a thing for ants?
I would never sell myself as a myrmecologist, an ant specialist, but
I am an evolutionary biologist. I (developed) an interest in these
particular ants, because they are fungus-growing ants that raise fungus
for food. People have seen stories about these leaf-cutting ants on the
Nature Channel or the Discovery Channel, but we’ve always assumed
they’re eating the vegetation they cut. But they can’t eat the stuff
they are bringing into their colony. We’ve discovered that they are
farmers. They take those leaves and clean them up and tuck them in
their fungus garden. We have a fungus-farming ant species of our own
here that lives below ground, Acromyrmex versicolor, but their
queens produce males and females, like all other fungus-farming ant
species.
They farm the fungus?
Yes, the ants constantly tend their fungus garden. They bring the
vegetation down underground into their nest and tuck it into the fresh
portion of the fungus garden, and in turn, the ants depend on the
fungus. … If you remove the ants, the fungus dies.
But Mycocepurus smithii ants are special because
they also happen to be asexual, right?
It was news, because based on current information, they appear to be
completely different from all other ants. With Mycocepurus
smithii, it appears that the daughters of queens are clones of
their mother. That’s the reason why this study made the news. The
workers are sterile, and they don’t reproduce—that’s fairly
typical for most ant species. But with this species, the queens
maintain sexual reproduction. A colleague of mine is working on looking
at this more; he’ll have a finer look at exactly what the genetic
mechanism is that allows them to do this. We can say cloning, but how
it happens, specifically, we don’t completely know yet.
What made you get into these ants to begin with?
We wanted to understand when they switched to fungal crops and
whether this caused the ant species to change and diversify into new
species of fungus-farming ants. … We didn’t find males in the wild,
and found that they didn’t produce males in the lab, and there are no
records of males. … Importantly, a colleague examined the queens’
internal reproductive parts and found that Mycocepurus smithii queens lack an internal mating structure that all other fungus-growing
queens have.
How do they differ from typical ant colonies?
The queen in this ant species produces new queens and female
workers, but never produces males. However, in most ant species,
colonies are usually run by the ladies as well. Her offspring, her
daughters, maintain the colony. In all other ant species, males are
generally produced when the colony is ready to reproduce … For all
other ant species, the males are done after they provide their genes.
Then the new queens go on and produce their own colonies. With
Mycocepurus smithii, the worker daughters are sterile, and the
queen produces the eggs. The workers feed the larvae—the stage
after the eggs—the fungus, which determines which ones will
become workers, and which ones become queens.
This article appears in Aug 13-19, 2009.
