Last week I received the kit in the mail.

Each kit comes with four vials with blue caps, four vials with red caps and one large tube with an orange cap. The red and blue-capped vials come [...]]]> You might recall that School of Ants is a citizen science program based at North Carolina State University (earlier post).

Last week I received the kit in the mail.

Each kit comes with four vials with blue caps, four vials with red caps and one large tube with an orange cap. The red and blue-capped vials come baited with cookie crumbs and are to be placed in specific setting. The orange-capped tube is for anything else you would like to have identified.

The next day I placed the open vials outside as directed.

The southern fire ants were happy to cooperate and soon were carting away bait.

I thought this was a perfect opportunity to learn more about ant ecology.

Ecologists who study interference competition often use baits. They recognize three strategies used by ants in finding and taking baits:

• Opportunists- able to find baits quickly, but don’t defend it
• Extirpators- may take longer to find bait, but recruit higher numbers and defend the bait (often have soldier caste)
• Insinuators – ant species that are too small in size and number to be noticed by extirpators

In this case the southern fire ants found the baits quickly, and were also defending. They definitely fit the definition of extirpators.

What about the tiny rover ants that are also found in the yard? Are they small enough to be insinuators?

Notice the rover on the top of the vial? Those are fire ants on the rim.

Will the defender ignore the rover ant?

No, the defender fire ant charges the rover ant and chases it away.

Let’s take a look in another tube.

Once again the rover ant approaches from the top.

Along comes the fire ant…

and chases it away.

In the end, the southern fire ants were able to dominate the baits. Looks like rover ants are opportunists rather than insinuators, in spite of their small size and lower numbers.

The bottom line is that baited vials are definitely useful for learning more about the ants in your area.

I would recommend this project. You do need to provide an envelope and postage to send the vials back, but otherwise time is the main investment. If you decide to take part in School of Ants, I’d love to hear what you find out.

Reference:  Parr, C. L. and H. Gibb. Competition and the Role of Dominant Ants, Chapter 5. In: Lach, L. Parr, C.L. and K.L. Abbott., eds. 2010. Ant Ecology. Oxford University Press, Oxford.

Of course [...]]]> The opportunities to participate in citizen science projects are growing by leaps and bounds. The Network for Citizen Science has a good sampling of the projects, some of which you might find interesting. Projects range from beespotting to banding oystercatchers, and you can devote as little or as much time as you have available.

Of course we had to use the Project Finder on the website to find projects under the keyword “ants.” I found two projects that are both child/family friendly.

1. Bay Area Ant Survey

The first to come up was a survey of ants around the San Francisco Bay area, sponsored by the California Academy of Sciences. I had already mentioned this one in my post about the Ants at the California Academy of Sciences. This is a great project to take part in if you live in California.

2. School of Ants

This new project involves gathering samples of ants from urban areas throughout the United States and is open to virtually everyone. To participate you simply need to visit the website and order an ant sampling kit. The kit will contain vials with a cookie bait inside. Place the vials outside as instructed and then after an hour, send back any ants you have captured. The ants will be identified and recorded on a map. The good news is that the project is supposed to be carried out worldwide eventually, although I’m not sure how they are getting the samples through customs.

Looks like some of the members of the group, based at North Carolina State University, have already made some interesting discoveries.

I’d love to hear from you if you decide to participate, and be sure to let me know what you find out.

Cookie loving ants from Arizona

Seems like there has been a lot of press lately about the “zombie ants” caused by fungi of the genus Cordyceps. The afflicted ants stagger about before they die, hence the name “zombie.” At the time of death [...]]]> Note:  The following post is not for the squeamish. You probably shouldn’t watch the videos right before lunch.

Seems like there has been a lot of press lately about the “zombie ants” caused by fungi of the genus Cordyceps. The afflicted ants stagger about before they die, hence the name “zombie.” At the time of death the ant typically attaches itself to a leaf and becomes a stiff fungal-spore salt shaker.

David Attenborough gives a good introduction to the fungus:

Of course, myrmecologists have known about Cordyceps for a long time, but the new interest has lead to some cool new discoveries. In the article by Bateman, it is suggested that the chemical produced by the fungus that makes the ant stumble around may be similar to LSD. Also, weaver ant workers may be able to recognize diseased individuals and may have some behaviors to cope.

The video that accompanies the Bateman article:

Do you think this research would have gotten as much press if they had merely said the ants were infected by a fungus?

For more information:

Daytime bites for zombie ants:  Final death grip for the living dead of the insect world comes at midday by Susan Milius at Science News explores fungal infection of Camponotus leonardi.

Green ant ‘zombies’ affected by deadly fungus attacked by slayers – latest scientific research by Daniel Bateman

Whether or not social insects sleep is a question that has gotten some definitive work in the bees. In fact, there are bees that are affectionately [...]]]> If you have ever watched the ants in an ant farm, you have probably noticed ants sitting around seemingly doing nothing. This leads to the question: are the ants sleeping?

Whether or not social insects sleep is a question that has gotten some definitive work in the bees. In fact, there are bees that are affectionately called “sleeper bees” for their behavior of resting on plants in clusters over night.

For example, these long-horned bees of the tribe Eucerini (named for the long antennae present on males), are often seen resting in clusters on plant stems. Other bees and even wasps have been known to “sleep” over night in flowers.

Recently, Klein et al. conducted an experiment on sleep in honey bees. They showed that depriving worker honey bees of sleep during the night, using a magnetic device, actually effects their ability to perform waggle dances the next day. Discover Magazine has an article with a brief video of sleepy bees dancing, shown here (with a sponsor ad at the end).

What about ants? Do ants sleep?

Many myrmecologists have noticed that a certain portion of ants in laboratory colonies spend a lot of time doing nothing. Blaine Cole (1986) reported that workers of the ant Leptothorax allardycei spent up to 55% of their time resting, which he called quiescent. Nigel Franks’ group writes that Leptothorax acervorum workers in the nest are inactive for 72% of the time and and foragers 15% of the time (Franks et al. 1990) and that Temnothorax albipennis workers are inactive about the same percentage of time in small colonies (44%) as in large colonies (46%) (Dornhous et. al. 2009).

None of these scientists have actually gone as far as to say these ants are sleeping though.

Deby Cassill in 2009 broke with tradition and calls certain periods of rest in ants “sleep.” Working with fire ants, she videotaped ants in an artificial nest. She created an artificial colony with three queens, 30 workers and 30 larvae. Checking the posture and position of the antennae, she concluded that queens sleep 90 times per day for 6 minutes per nap, whereas workers dosed 250 times per day for roughly one minute at a time. You can see a video of the set-up at the BBC Earth News.

Cassill even went as far as to label Rapid Antennal Movements (RAM) as the invertebrate equivalent to Rapid Eye Movement (REM) sleep in vertebrates. Her conclusion: yes, ants sleep.

Ant napping?

Are we ready to agree?

1. What do you think about the studies that observe ants spend a lot of time doing nothing?

My thoughts:  One thing that is immediately apparent in contrasting the honey bee studies with the ant experiments is that an artificial honey bee hive is much more “natural” than a laboratory ant nest. In a demonstration hive the bees usually have access to outside foraging, they have comb, they are going about their business as usual.The ants, on the other hand, have no soil to move, no myrmecophiles to interact with, no predators, no opportunity to move brood to optimal locations, etc. etc. It seems evident that greatly reducing the number of available tasks at hand limits the conclusions that can be made about the behaviors observed.

2. Can ants, or even insects, sleep?

My thoughts:  Seems like a reasonable idea, especially looking at the honey bee study.

3. What do you think of the “power nap” finding with fire ants?

My thoughts:  Having spent some time filming ants, I know that they are sensitive to vibrations we humans do not even notice, such as the laboratory incubators coming on and off in the room next door. I don’t have a copy of the paper yet. Does anyone know whether Cassill placed her artificial nests in such a way to minimize artificial disturbances, for example, placed them on vibration dampening pads? If not, it seems possible that something was disturbing those ants to keep them awake more often than usual.

What do you think?

References:

Barrett A. Klein, Arno Klein, Margaret K. Wray, Ulrich G. Mueller, and Thomas D. Seeley. 2010. Sleep deprivation impairs precision of waggle dance signaling in honey bees. Proceedings of the National Academy of Sciences (PNAS). 107 (52): 22705-22709.

Deby L. Cassill, Skye Brown, Devon Swick and George Yanev. (2009), Polyphasic wake/sleep episodes in the fire ant, Solenopsis invicta. Journal of Insect Behavior. 22 (4):  313-323.

Cole B. (1986). The social behavior of Leptothorax allardycei (Hymenoptera,
Formicidae): time budgets and the evolution of worker reproduction. Behav Ecol Sociobiol. 18:165–173.

Anna Dornhaus, Jo-Anne Holley and Nigel R. Franks. (2009). Larger colonies do not have more specialized workers in the ant Temnothorax albipennis. Behavioral Ecology. 20 (5): 922-929. (full text available online free)

Nigel R. Franks, Steve Bryant, Richard Griffiths and Lia Hemerik. (1990). Synchronization of the behaviour within nests of the ant Leptothorax acervorum (fabricius)—I. Discovering the phenomenon and its relation to the level of starvation. Bulletin of Mathematical Biology. 52( 5): 597-612.

Oh my, what fun it must be to spend your day playing with a leafcutter ant colony. I want a job like that!

Edit: Myrmecos has a post about the research paper.

Are you making resolutions and setting goals for the New Year? Thinking of polishing up your ant taxonomy skills? You might want to consider adding the California Academy of Science’s Ant Course 2011. You can bet it is on my wish list!

This year the ant course is being held August 4 – 14, 2011 [...]]]> Happy 2011!

Are you making resolutions and setting goals for the New Year? Thinking of polishing up your ant taxonomy skills? You might want to consider adding the California Academy of Science’s Ant Course 2011. You can bet it is on my wish list!

This year the ant course is being held August 4 – 14, 2011 at the Southwestern Research Station in Portal, AZ, USA.

California Academy of Sciences offers an ant course every year in different locations. According to the website, it is open to all interested individuals. Because space is limited to 30 students, however, priority given to students with who need the course for their research. I wonder if ant bloggers are invited to hang out?

You’ll need to make up your mind by April 1, 2011, which is the application deadline.

If you are unsure, take a look at the instructor list from last year. Wow!

Arizona

Do you know about fluon, the slippery white material that is essential to keep ants where you want them (at least as much as possible)?

It is available at that old standby of insect supplies, BioQuip as

Insect-A-Slip Insect Barrier – Fluon

It isn’t cheap, but you don’t need very much.

Yeah BioQuip!!!

This week my son and I have been watching a toothbrush. No, we haven’t gone bonkers. This does have something to do with ants.

You see, we saw this post about an unusual Ant-traction. It seems that a certain type of ant likes the rubbery buttons Colgate toothbrushes. Go check it out. Here’s a link to [...]]]>

This week my son and I have been watching a toothbrush. No, we haven’t gone bonkers. This does have something to do with ants.

You see, we saw this post about an unusual Ant-traction. It seems that a certain type of ant likes the rubbery buttons Colgate toothbrushes. Go check it out. Here’s a link to the original post, as well.

The first thing we wondered, of course, was whether this is a prank or hoax. I think you could get the same effect by rubbing a little sugar water or honey on the brush.

We bought a toothbrush to check it out. So far our fire ants, Solenopsis xyloni, could care less about the toothbrush. But that doesn’t mean the effect isn’t real. It could be that the rubbery bit contains a pheromone specific to one or a few closely-related species of ants. We are going to continue our experiments.

If there turns out to be something to this, it won’t be the first time humans have inadvertently produced a product that mimics an insect pheromone. One classic example is the finding that termites of the species Reticulotermes flavipes will follow an ink trail drawn by a certain type of pen. (See for example, this experiment).

If you’d like to learn more, here is a video showing EO Wilson explaining some of the basics of pheromones and other chemical signals in ants:

We’ll let you know if we get any ants to react.
And please let us know if you try this experiment, what your results were, and what kinds of ants you used.

It turns out that ants can make plenty of music. They can squeak, drum and rattle as well. There is nothing quiet about ants. As Dr. Francesca Barbero of the [...]]]> I’ve just been reading a book on katydids, which are insects renowned for their ability to sing. What about ants? Are they the strong silent types?

It turns out that ants can make plenty of music. They can squeak, drum and rattle as well. There is nothing quiet about ants. As Dr. Francesca Barbero of the University of Turin says,  “Sound in information exchange within ant colonies has been greatly underestimated.”

Stridulation

Detail of the pars stridens (in yellow) on the forth abdominal tergite in a Pachycondyla villosa worker (Scanning Electron Micrograph, Roberto Keller/AMNH)

Ants with underground nests occasionally get buried when a tunnel collapses. Scientists have shown trapped ants of certain species can make sounds by rubbing sections of their rear section or gaster together. On one segment of the gaster there is a patch of tiny ridges like a file. On the petiole is a curved ridge called a scraper. The ant produces a squeaking sound when she rubs them together, which known as stridulation. You can produce a sound in a similar way by rubbing a craft stick across a comb. When other workers detect the sound, they rush to help dig out the trapped ant(s). (Be sure to visit Roberto Keller’s website for more SEM views of the apparatus).

Researchers have been able to record sounds from individual ants. The sounds are in the audible range for humans and can be heard distinctly when amplified. Listen to the sounds of a fire ant stridulating at Stridulation Sounds of Black Fire Ants by Dr. Robert Hickling.

Stridulation has other functions as well. Male and female harvester ants sing to one another as they take off on their mating flights. Mated females also stridulate to signal to pursuing males that they are no longer interested. In other species, foragers may stridulate when they find food to attract help, although they often release pheromones as well.

Leafcutter ants are known to stridulate while cutting pieces of leaf. It appears the noise the cutting ants make attracts other ants to come take the pieces of leaf to carry them back to the nest. Some ant scientists have suggested that the vibrations improve the ants’ ability to cut smoothly through the leaf. Leafcutter ants also produce sounds while building their nests in the soil.

Example video of Acromyrmex ant stridulating

Some other insect species associated with ants also stridulate to attract the ants’ attention. The caterpillars of the beautiful Imperial blue butterfly have “teeth” on their abdomen, which they scrape against a series of grooves to produce grunts and hisses. They can also make a drumming sound. All these different calls seem to be used for different situations, but not all the details are clear yet. What is known is when scientists glued up the noise-producing organs with shellac, the ants took longer to find the caterpillars and spent less time with them than with the ones who had not been silenced.

As I mentioned in the post about blue butterflies, Rebel’s large blue (Maculinea rebeli) larvae have recently been shown to mimic the sounds produced by the queen ants of their hosts to elicit food, care and even rescues, at the expense of the colony’s own offspring. Go to “Caterpillar noise tricks ants into service” article at Science News to actually hear the sounds the caterpillars and ants make.

Drumming
I studied carpenter ants, and whenever I opened a nest, I could hear the ants react. The workers strike their mandibles and gasters on the surface of the tunnels in their wooden nest to create a drumming sound. Ants deeper in the nest rush to the site of the disturbance and assist their sisters with defending the nest.

Rattling
The rattle ants of Australia also tap their gasters when they encounter an enemy intruder, such as a bird feasting on their nestmates. They live in leaf nests high in trees. The leaves may be slightly dry and the tapping produces an audible rattling sound that gives these ants their name.

Rattan ants of Asia live in thorny rattan vines. When an intruder gets too near their nest the ants hit their mandibles against the stem of the plant. Because they hit in a synchronized way, the sound pulses. (I was interested to learn that some katydids also drum or vibrate the plants, especially species that stay hidden deep in foliage. )

Where are the ants’ ears? No one knows for absolutely sure how it all works. Some ants have ways to detect surface vibrations in their legs. It is also likely that certain ants use hair-like sensors in the tips of their antennae. When the hairs are displaced the ants detect signals that are called nearfield. Those are signals from sources that are extremely close. The ants remain completely unaware of sounds produced by far objects, like us shouting at them for example.

In any case, as our human sound equipment becomes refined, I’m sure we will be hearing more from ants.

More sound recordings:

Take a look at how ants respond to a microphone and listen to a recoding by by Adriano Zanni.

Bug Bytes, the USDA Sound library of Richard Mankin, has a number of ant recordings.

References:

Barbero, F., J.A. Thomas, S. Bonelli, E. Balletto, and K. Schönrogge. 2009. Queen Ants Make Distinctive Sounds That Are Mimicked by a Butterfly Social Parasite. Science 323 (5915) 782.

Donato A. Grasso,  Marco Priano,  Gianni Pavan,  Alessandra Mori,  Francesco Le Moli. 2000. Stridulation in four species of Messor ants (Hymenoptera, Formicidae). Italian Journal of Zoology, Volume 67, Issue 3: 281 – 283

Judson, Olivia. 2009. Operator? Can You Put Me Through to Ant Nest 251? New York Times – gives an historical perspective of some of the earlier works on ant sound communication.

Markl, H. 1965. Stridulation in Leaf-Cutting Ants. Science 149 (3690), 1392-1393.

Tautz, J., F. Roces, B. Hölldobler. 1995. Use of a Sound-Based Vibratome by Leaf-Cutting Ants. Science 267 (5194), 84.