Ant-collecting

[rebeccmeister]

The most I can offer in the way of compensation for my abrupt disappearance from Seattle is a brief photo-documentary about what I have been up to in Arizona in the meantime.

During the early part of my travels to Tucson, I had to do the majority of my field work at night, which makes taking photographs rather difficult. So the below photos are from the final day of ant-collecting, when I found a swarm. There are also photos from the following days when I returned to the lab to observe the queens' behavior.

You can click on the pictures to view larger versions.

Driving to Tucson at 5 am.
Sunrise on I-10 The picture doesn't do the sunrise justice. Too bad you missed it. It was the most incredible sunrise I've ever seen.
The Swarm As I drove along Skyline Road in Tucson at about 20 mph, I spied a swarm at about 6:45 am. Hooray!
Mating ball By the time I reached the mating swarm, most of the females had come and gone, so there was fierce male-male competition for the remaining females. [Insert jokes comparing ant mating to human mating behavior here] In the middle of this mating ball, there's a queen somewhere.
Collecting from the swarm I picked up queens and males from the ground, separated out the queens from all but one male, and put them in small plastic tubes that are about 1.5 inches long for transport back to the lab.
Handling ants As long as you are somewhat gentle, it's usually easy to pick up ants without hurting them.
It's raining ants! Hallelujah.
My recently purchased broad-brimmed hat sure came in handy in the ant-rain. Also, this time I wore a shirt that could be tucked into my pants. So you could say I learned a thing or two from the previous time.
New ant nest That's one of those 1.5-inch tubes next to the hole, for scale. It's a bit blurry, but here's what a fresh ant-nest entrance looks like. When queens start digging new nests, they will carry pellets of soil up to the surface about once every 30 seconds, drop them on the ground, and run straight back into their new nest. If I spied a queen from the corner of my eye, I would wait for her to reappear and would pick her up and put her in a tube. This carried on until it got too hot (at about 9 am), when any remaining queens retreated underground. The queens usually re-emerge at night, when it's much cooler, to continue excavating and to forage. That's when I was able to collect the initial set of queens.
Nests in the laboratory Here's a set of 9 lab nests. The purplish petri dishes in the center of the picture contain dental plaster, which is kept moist to provide the ants with a source of water and a nice place to grow fungus. They are connected by a short piece of plastic tubing to the clear dishes on the outside, which are foraging chambers. That's where I provide leaves and other materials for the ants to collect and use to grow their fungus.
A single colony, viewed from above. These colonies were named after fruits and vegetables. So there.
Three queens and fresh fungus I put a dab of paint on the gaster (last body segment) of each queen so I can distinguish individuals from each other--you can kind of see a bit of white and a bit of pink paint in this photo. In this nest, the queens have expelled a small fungus pellet and are gathered around it, willing it to grow larger. If you listen really closely, you can hear them chanting, "Grow! Grow! Grow!" To the left of the queens is a bit of leaf that they have foraged and will probably add to the fungus.
The three queens from above, still gathered around the fungus.
Queens chewing up leaves The queens will chew up leaves into tiny fragments, lick the pieces clean, and then attach them to the fungus.
Queens adding leafy bits to the fungus. Mmm, leafy fungus. Here you can clearly see pink, white, and silver paint marks. Attractive color scheme, no?
Side-view of queens hanging out in the nest. At this stage, queens will lay eggs on the fungus, which will hatch into larvae. The larvae will then feed on the fungus and grow larger and larger, until eventually they metamorphose into pupae and then turn into adult workers. Once workers appear on the scene, they gradually take over all of the tasks in the nest aside from egg-laying. This is called reproductive division of labor. We are interested in quantifying the transition from queen task-performance to worker task-performance in these nests.

Comments

[zoobar.livejournal.com]

This is really cool! Thanks for posting this!

[bluepapercup]

This was totally fascinating.

Thanks for the look into your work and your scientific/research process!

My body of random knowledge is discovered to be crap.

[global-keewee.livejournal.com]

So have I mentally cataloged incorrect information for the past 15 years since taking my last (and only) biology class?
I though that the big butt section of an insect was the thorax. You have called it a gaster, which I assume is 100% correct because you study this and are far more capable than my teacher in 9th grade so win by default. What the heck is the thorax, then?

Re: My body of random knowledge is discovered to be crap.

[rebeccmeister.livejournal.com]

So most insects have three body segments, which go in the order head-thorax-abdomen. However, ants are somewhat strangely shaped--some of the segments that are "normally" part of the abdomen are fused with some of the segments of the thorax. So the mid-segment of an ant is called the mesosoma, and the last segment is called the gaster. Interesting, no? :)