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A quick note to let you know I'm going to be doing a bit of spring cleaning behind the scenes on this blog (which means rooting out bad PHP, changing themes, and converting to https).

Hopefully things will continue working without too much interruption.  In the meanwhile, enjoy this photograph from the Insects Unlocked Public Domain photostream.

If you live in the North, you might be wishing for an ant sighting about now. The grass is brown and the trees have shed their leaves.

Well, maybe not all the trees. When I went out for a walk I noticed the African sumac, Rhus lancea, has a spread of yellow-green material beneath it. Is it pollen?

I had to check it out, of course.

The tree is flowering.

It isn't pollen on the ground. Instead, it is a layer of dropped flowers.

What's that bright cluster?

There's another.

And another, each with an entrance hole in the center. There are eight or nine bright green clumps in all.

It seemed likely they are ant nests.

Can you spot it? Yes, an ant!

They look like Tetramorium or pavement ants.

 

One by one the workers carry a flower into the nest entrance and disappear.

 

The pavement ants are apparently taking advantage of a local abundance during the slow winter months. (The ant is blurry, but I thought the pollen on its head was cool.)

Seeing some ants at work in January? That is an unexpected bounty for me.

Have you ever seen Tetramorium gather flowers or other plant material?

Today we're featuring Kaitlin M. Baudier, PhD who is currently a post doc in the Social Insect Research Group at Arizona State University.

Dr. Baudier is the creative force behind the AntGirl YouTube Channel. Check it out, particularly the ant playlist.

To give you an idea of her content, here's her video of a Pogonomyrmex barbatus mating swarm.

Isn't that incredible? Being close to a social insect swarm is an amazing experience. I hope to see a full blown harvester ant mating swarm like this one some day.

What else does she work on?

Besides social insect swarm aggression research, she also studies tropical ecology and animal behavior. She has some great videos of tropical species, like the ants versus stingless bees.

Ever seen those odd tubercles on ponerine larvae?  (If not, the Mississippi Entomological Museum has a close up of an Ponera pensylvanica larva here.) Dr. Baudier is also interested in studying their evolution throughout the subfamily ‎Ponerinae. Take a look at her poster about "sticky fingers."

If you'd like to learn more, visit her website.

Did I mention she's also an artist?

You've probably seen the videos of people drawing circles around an ant and the ant seeming to refuse to cross the line, like this one:


Recently this question came in:

My son wants to do a science project related to a video he saw about ants not crossing a marker boundary. We assume this has to do with pheromones or rather chemicals in the markers. We have tried to find research related to this, however very little has been found by him. Wondering if you know of any research about this?

Before going into the question, first let's make sure we are clear about terminology. A pheromone is a chemical scent that animals use to communicate with other members of their species. (You can see more about ant pheromones in this previous post.) An ant repellent, on the other hand, is any chemical that keeps ants away. They are not, however, mutually exclusive. It is possible for a pheromone to repel other members of the colony, for example virgin queen honey bees produce a pheromone that tells worker honey bees to back off.

Returning to the marker problem, what could be going on?

It could be the chemicals in the marker act as an ant repellent. The ant is repelled by the line and refuses to cross it. It makes sense that ants respond to any novel or harmful chemicals by backing away or avoiding them.  In a paper in Journal of Chromatography A, scientists found all sorts of chemical compounds in pen ink that ants might want to avoid, including methylbenzene and xylene.

Another possibility that the marker has wiped away the trail pheromone trail that told the ant where to go.

Foraging ants that find food mark the surface with chemicals as they return to the nest. As more ants pass back and forth, more and more pheromone builds up. Depending on the foraging strategies of the ants, some trails can be dense with worker ants. Similarly, when ants are moving from one nest to another, they will lay and follow a pheromone trail.

You can disrupt a pheromone trail with chalk or even with your finger.

The behavior looks pretty similar doesn't it?

A third possibility is that it is a little bit of both: the marker wipes away the trail and also repels the ant.

Rather than give you all the answers, think about way you might be able to figure out which of the possibilities are likely and how to test for them. A hint: what happens if you draw a pen circle around an insect or spider that doesn't have a pheromone trail? Do they act the same way?

For more help, check out Drawing Circles Around Ants and Go and Stop? Ant Traffic at the Science Buddies Website. (Always a great resource for science fair project ideas.)

Public domain image of army ants by Alex Wild.