July 2012 Archives

How far back does speculation go regarding the ancestry of ants? I have found that ants are thought to have come from wasps and I was wondering if speculation went further back to an ancestor for wasps etc. Is there a common ancestor that goes back to the sea?

Another question that I have is rather or not some wasps or wasp like creatures could have evolved from a line of ants, in other words the reverse of the theory that ants evolved from wasps?

Lastly, I am fascinated by ants that have an iridescent or blue hue and I found bees on-line that have an iridescent metallic green turquoise color. Is there an ant with a comparable appearance to this type of bee? Could these be related to the metallic bees? They look surprisingly alike.

Dear Pamela,

Ants and wasps are insects and are therefore members of the subphylum Hexapoda. Hexapods in turn belong to the phylum Arthropoda which includes crustaceans (crabs, lobsters, shrimp), myriapods (centipedes, millipedes), and chelicerates (spiders, scorpions, horseshoe crabs). All of these groups likely evolved from a shelled, aquatic ancestor. The evolution of land-dwelling behavior from aquatic ancestors appears to have occurred several times within this group. You should take a look at this study by Regier and colleagues and definitely check out Alex Wild's blog post discussing this paper.

Some of the strongest evidence that wasps are ancestral to ants and not the other way around is that the oldest known ant fossils are from about 100 million years ago, whereas the oldest known wasp fossils span back to around 150 million years ago. The changes in physical characteristics are also suggestive of a wasp to ant transition as an ancestral ant would mean that wasps had to reacquire wings and the ability to fly, rather than the far more likely loss of wings in ants. Lastly, phylogenetic analyses show that the ant clade (Formicidae) consistently nests within what we consider to be wasps, suggesting that ants are derived from a wasp-like ancestor (see this paper by Pilgrim and colleagues). All of this evidence taken together mean that it is far more likely that ants evolved from wasps than vice versa.

Ants and bees are related but every ant is more closely related to all other ants than they are to any bee. The same is true of bees in relation to ants. This means that the iridescent green color that is found in both ants and bees is a result of convergence to that character, not the close relationship of a particular pair of ant and bee species. In fact, there are many wasps that also have this type of coloration (see some of Alex Wild's beautiful photos here and here). These similarly colored species may use the same mechanisms for generating the necessary pigments, and these mechanisms may be present as a result of common ancestry but their expression is a result of convergent evolution.

Great questions!
Ben Rubin & the AntAsk Team

Today my nephew told me that he saw a bird fly into a window at his office. Later he went out and saw the bird, dead on the sidewalk. He went to lunch and upon his return he saw ants surrounding the bird and they appeared to have constructed, for lack of a better word, a wall, around the dead bird. He thought it was made of small pieces of gravel or something. Have you ever heard of this type of thing? If so, what were these ants up to??
Susan Gray

Dear Susan:

This is a common behavior among ants. There are various interpretations or reasons why they might do so.
- The ants may well have been building a sort of wall. A possibility is that the wall serves to help keep out other ants that might compete for the rich food source that a bird carcass provides for an ant colony.
- Another one is that the conditions on the surface of a sidewalk are rather harsh (hot and dry) for ants that are not moving (which would allow them to lose heat), so they may be burying themselves, so to say, to keep out of the full sun and stay a bit cooler.
- Finally, many ants place particles of absorptive material on moist prey as a means of soaking up the liquid, to carry home on relatively portable particles of drier material.
This is more typical of ants that have a relatively small crop (social stomach), including some ants in the subfamily Myrmicinae, army ants, and occasionally others. Ants with larger crops (other Myrmicinae, Pseudomyrmecinae, and especially, Formicinae and Dolichoderinae) can carry a surprising amount of the undigested liquid in this modified portion of their lower esophagus, then regurgitate it rather like a mother bird to share with nestmates.
None of these explanations is mutually exclusive, and the ants your nephew observed could have benefited from this prey-burying behavior in all these ways, and possibly others I have not even remembered to mention.

James C. Trager of the AskAnt Team

I just moved to Costa Rica for the next 5 or so months to a beautiful beach house. The bugs are hardly noticeable during the day, but when the lights go out...they come out to play. Since it is such an open home (literally doesn't full close) I get a bit creeped out at night.

Specifically there are these very large black ants; much larger than anything back home. After some online reading it seems that they might be Bullet Ants. Reading that they only come out when I sleep and have very painful bites...a bit unnerving. I don't mind running into them outside, but the prospect of meeting them in my sleep is really giving me the heeby-jeebies.

There is no food around where they are entering, I can't really find the entry point to block it, and I cleaned the area to try to remove any trails left behind. What can I do to create an ant free sanctuary in my bedroom at night? Being in a small surf town in Costa Rica, I'm not sure what products I can or cannot get my hands on...

Also, this spurred another question. After manually killing a bunch in my room the good-ole-fashioned 'shoe' way I began to wonder, will ants ever leave an area after seeing too many of their own dead? Or do they just blow on by without a care?




Dear Benjamin,

Without pictures it is hard to tell exactly what species of ants are raiding your bedroom at night, however, there are a few clues which provide enough evidence to give an educated guess. First, from the sounds of their behavior, it is unlikely that these marauders are Bullet Ants. For most people, a single bullet ant sting will incapacitate them for a day, and several in a night time might demand a trip to the hospital.

On the other hand, the western coast of Costa Rica is known for a black subspecies of army ant, Eciton burchellii parvispinum, that tends to frequently raid manmade structures in the day, evening, and night. They are much larger than most North American ants, come in great numbers, and also have very potent stings. Most army ants have a predilection for wasp larvae, and due to the high incidence of wasp nests on the eves of dorms and houses, the army ants will continue to return to clear them out. On the bright side, army ants are nomadic so they probably won't be around for long, but it could be as long as 3 weeks before they move their nest site. The best solution would probably be to get a netting for your bed so you can avoid contact and sleep in peace. They're cheap and you can rest easy as the army ants clean your beach house for you!

In response to your other questions, the answer depends on the species! Often, ants will release an alarm pheromone to communicate to other members of the colony there is a threat. For some species--even some army ants--this will cause the rest of the colony to avoid that area. However, if these army ants are the species I'm thinking of, they have colonies of with millions of workers, and make their living by overwhelming and consuming their prey. Often killing a few workers of an Eciton burchellii colony will just rile the rest of the workers up and incite further aggression.

Hopefully the bed-net solution works for you!

Max Winston & the AntAsk Team

Hi AntBlog,

I am an elementary school teacher and I am looking for a project to do with my students on ants? Do you have any ideas?

Thank you,

Dear Maria,

We are really glad you want to include ants into your classroom activities!

There are many potential ways to include ants into classroom and teaching, including 1) having a living ant farm in the classroom, 2) participating in the School of Ants, or 3) becoming an Urban Ant Collector.

Ant Farm: You can learn more on making your own ant farm and finding and/or purchasing ants for the farm here, here, and here.

School of Ants: School of Ants is a nationwide citizen science program interested in getting people from across the USA to collect their local ants and send them into a lab in North Carolina so they can make a map of all the ant species found. It is easy to participate and all you need are a few common items (read here for the list). Once you have put out your "baits" you just put them in the freezer overnight to kill the ants, and then ship them off for identification. Once identified you can log in and see what ant species your classroom collected! It is a great way to see not only your local ant diversity, but also how your ant community compares to other locations.

Urban Ant Collector: Using an Android smart phone app, you can collect ants like a professional while adding to our knowledge of the planet's biodiversity. You can read more about this program here.

Best of luck,
Corrie Moreau & the AntAsk Team

Hi, I am in Montenegro and have been observing ants on our terrace. I have been watching an apparently dead ant being approached by another ant. It appears to prod the "dead" ant. This often prompts some movement. It is as if the ant is trying to revive the one which is "dead". This behaviour goes on for a number of minutes. Sometimes the ant is joined by another member of the group which also seems to be attempting resuscitation. If there is no success the ant carries the body away. Can you explain this behaviour for me.

Thank you, Maureen

Dear Maureen,

Great questions! We have addressed similar questions about ants carrying other ants, both dead and alive, on AntBlog. You can find the answers to your questions in the following posts:


Keep watching ants!
Corrie Moreau & the AntAsk Team

At a trip today (July 10th) to Boise's MK Nature Center (operated by Fish and Game) our group of preschoolers found a pile of ants. I told them I wasn't sure what they were doing, but I would take a picture and ask someone. So, I found you online! These are just small black pavement ants, I believe. Any insight on what they are up to?

Thank you for your time,


Dear Tricia,

Thank you for sending in the photo of the ants your preschoolers noticed on your recent nature trip. Great find!

The ants are in fact pavement ants in the genus Tetramorium. Although this is a common ant found in urban environments, it can also be found in more natural habitats. Along with the pavement ant, there are likely dozens of other ant species in that same nature reserve, so keep your eyes open the next time you visit the reserve. Close by in the state of Utah over 150 species of ants are known (see the Ants of Utah on AntWeb.org).

You can read more about pavement ants here in a previous AntBlog post.

Thank you,
Corrie Moreau & the AntAsk Team


We have a thin crack in the concrete at our garage door. Tiny ants keep bringing up small particles of something. At first I thought they were in the wood door frame as the residue was piled along it. After taking trim off there were no ants.

Have placed terro at the action site but, they keep on coming. Have sprayed, it lasts a few hours and they are again active. Blowing forced air from an air compressor brings them up. Kill them with spray, squirt it in crack and the ants return next day.

The crack is too small to really get anything in it. What next??

Thanks, Fred, Ovid NY

Dear Fred,

Sorry to hear you are having problems with ants in your garage. Although ants are an important part of the balance of the natural world, unfortunately they can also become pests in our homes. Using commercial sprays is usually ineffective, since they only kill the few workers or foragers you see. The rest of the nest, including the queen, is usually far away (deep underground or inside wood or a tree), safe from the fumes of the bug spray. To truly eliminate the entire colony, you must find a way to kill the queen.

In previous posts on AntBlog (click here, here, here, here), we have outlined some general strategies for getting rid of ants including using commercially available poisons like Borax.

Best of luck,
Corrie Moreau & the AntAsk Team

I dug up a pogo ants nest and I have about 10 queen and 10 kings but none of them are fertilized how do I get them to mate?


Dear Jarvis,

We are glad to hear you are interested in ants! Unfortunately it is very difficult (and impossible for many species) to get ants to mate in captivity. Most ant species need to go on a mating flight, where unmated queens and males (these are often called "sexuals") leave their nests to reproduce based on environmental queues. During these mating flights, the sexuals from all the nearby nests will congregate in a single location to find mates. Below is an image taken by Alex Wild showing one of these mating swarms.

Mating swarm.jpg

Ant mating swarm - Photo by Alex Wild (www.alexanderwild.com/)

For more tips on keeping ants and getting mated queens for your ant farm, see the following three posts here, here, and here.

Best of luck!
Corrie Moreau & the AntAsk Team


We are the Dolphin Class. Teacher Chelsea is here with Felix, Daniel, Sean, Andrew, Wayne, Evelyn, Kate, Ginny, Ethan and Aaron. We really like ants.

Here are some of our questions:

We want to know, how many different kinds ants are there? Why do ants line up when they walk? Why are ants small? What is the difference between red and black ants? What color of ants are there? Why are ants bugs? Why do ants like to eat what people eat?

The Dolphin Class


Hi Teacher Chelsea, Felix, Daniel, Sean, Andrew, Wayne, Evelyn, Kate, Ginny, Ethan and Aaron (the Dolphin Class),

According to the AntWeb homepage, one of the most up to date and accurate resources for ant taxonomy, there are currently 14,891 ant species known to science. (We have a previous post on ant species diversity here.) These species have been described in detail by expert ant researchers around the world. However, there are likely several thousand more species that have not yet been found or researched so if you start collecting ants now, you could very well find a species that no one has seen before.

Ants leave scent trails on the ground when they want other members of their colony to be able to follow the same trail. This behavior often results in ants moving in a line down the narrow path laid by ants that have gone before. They lead each other around in order to share the location of high quality food resources, move to a new nest site, or even raid other ant colonies. Take a look at this post for a little more information. And speaking of food resources, ants like the same food that people like because they are rich in nutrients that the ants can use to grow and feed their larvae. The very same reasons that we like them!

Ants come in a wide range of sizes and colors. This post gives some details on the largest and smallest species and explains that the largest ants are 3 cm long! Not very small at all. As for colors, you already know that ants can be pure black or bright red but they can also be anything from brown to yellow. Colors often tell little about the differences between ants as they can be quite variable even within species. As you can see in these pictures taken by Alex Wild, there are even bright, golden and green ants.

Above: Camponotus seriveiventris. Below: Oecophylla smaragdina. Photos from http://www.alexanderwild.com.


We are very glad to hear that you like ants so much! Keep thinking about them and ask your teacher as many questions as you can!

Ben Rubin & the AntAsk Team


I recently visited and isolated mountain is central Montana where I have visited from time to time for about 45 years. The mountain, known as Square Butte, rises from the badlands country of less than 4k feet above sea level to an elevation of about 5600 feet. Dry but timbered. Not much for soil.

This time we experienced a presence of ants, mostly the "red ants", that are very common throughout the area, in numbers none of us have ever experienced in all our collective time outdoors in Montana. The nearby ranch owner who has been on the mountain more than probably anyone, has never experienced this phenomenon before either.

There is hardly a yard large space in hundreds of acres at a time which is not crawling with the ants. And extraordinarily large ant hills. The nearby ranch owner who has been on the mountain more than probably anyone, has never experienced this phenomenon before either. 2011 was an epic year for moisture in the area. More rain and snow than a normal 3-5 year period. What do you think might have happened here?


Hi Larry,

We have contacted James Glasier, antweb's Alberta ants curator, for help with your question and here is what he had to say:

"If the area was timbered, I would probably guess Formica rufa group ants, but he also mentioned badlands, which could indicate Pogonomyrmex, like Dr. James Trager said, so any pictures would make identification easier. The density of ants seems extremely high from his description and I have not seen anything like that. I have had reports of large colonies of Formica podzolica in the last few years that just appear in farmer's yards where they weren't there the year before; colonies three to five meters in diameter compared to regular one meter nests or smaller. I have also had a few people report in southern Alberta an increase in large Formica obscuripes mounds. So it is quite possible these are indications of increased ant populations. I personally haven't collected ants in Montana and don't know the area he refers to, so I can't say for sure what else may be going on... is it possible to get pictures? The other potential thing I could think of is a large nuptial flight occurring right when he was in the area. I know Formica rufa species can be quite aggressive when nuptial flights are going on and run a round quite a bit, and Pogonomyrmex can do that in large numbers as well... so that may also have been what was happening where he was."

Hope this helps,
James Glasier (guest expert), Steffi Kautz & the AntAsk Team


Thanks for writing such an awesome website! Would you please help me.
I have several panes of glass and instructions on how to build an ant
farm. That's not the problem. The problem is where do I get ants from?
I live in Northeast Arkansas and I do see ants outside, mainly little
black ones. A day ago I saw larger red ones going through my garden
collecting every insect they could find. Today they were nowhere to be
found. Do I always need to start with one queen? Do I just dig one up.
Hope you can help me. My son is very impatient :) He wants his ant
farm. Well, I am just as eager to get this going too.

Thanks for your time,

Hi Daniel,

Thank you very much for contacting us! It is a very common question how to get ants for an ant farm and we have several posts on the topic. Check out this link:


If you want some ants quickly, I suggest just collecting a bunch of workers from one colony. They will die within a couple of weeks, but your son will have something to look at in the meantime and it will be interesting to observe them for a while. After most or all the workers have died, remove the remaining once and add new once. Without a picture, it is always hard to tell which ant species you might have encountered. However, largish red ants in NE Arkansas are probably a Formica species. They do not sting, but are very fast-running and a bit difficult to catch. Right now it's so hot and dry in that part of the country that all the ants have gone pretty deep under ground. Still, early in the morning, one might be able to find some near the surface, in their mounds (Formica builds mounts), or under cover objects such as rocks, logs and boards. It will be easier after we finally get some rain, though!

Good luck,
James Trager, Steffi Kautz & the AntAsk Team

Hey there!

I am currently doing an experiment on ant repellent and I noticed something weird which I would like to inquire about. For my experiment, I used chicken skin as the attractant to test whether the repellent works. I was hoping to get the same type of ants for all the set-ups so that my experiment will be fair. However, one of my set-up had black medium-sized ants attracted while the other had small red ants and medium-sized, big head red ants attracted. Both set-ups were done at the same time under the same conditions. I was thinking whether it is because the black ants and red ants were of different colonies/groups and do not mix and have their own territory. (The 2 different types of red ants could be from the same family/species.) So when any one type of the ants leave their scent on the chicken skin, the other type of ants will not come and invade their territory when they smell a foreign scent and the same type of ant will come instead when they smell the particular scent from their same kind. Thus, whichever type of ant that stumbles first on the chicken skin and leave their scent, that chicken skin will be invaded by that type of ant. Is my reasoning correct? Also, is there any way to only attract one type of ants? Because my experiment can only have 1 type of ants to be fair.

Thank you!


Hi Janelle,

Thanks for your interesting question and sharing your observations with us!

Without a picture, it is always hard to tell which ant species you encountered. Information on your location would be very valuable to get an idea on the ants identity as different ants are distributed in different parts of the world.

Ants of a single species often have the same color. This means that the red and the black ants you observed most likely belong to two different species. However, the red small ants and the red bid headed ants might actually be different casts of the same species. For example, there is an ant genus named Pheidole, which has two or sometimes even three different casts. The big headed individuals are called the soldiers or major workers, while the little ones are called minor workers (but as any ant workers, these are all sterile females). Here is a picture of two ants from the same species and even same nest. In this picture, you see that not only is there a distinct difference in size and morphology (i.e., shape), but also the color between the two individuals differs.


Pheidole barbata - an ant species with two distinct casts. Photo from http://www.myrmecos.net.

As for whether ants are deterred if a different species has left pheromone trails, I think it depends on the species identity. A dominant species would not care, while a more timid species might be repelled.

For your experiment, I think that it does not matter whether you attract ants from one or more species. You could just note how many individuals of how many different types of ants were attracted (as species is sometimes hard to distinguish). Another approach could be that you go out and collect a bunch of ants from a single nest and then test their reaction to the chicken skin in a plastic box. This would also control for other factors, such as soil type etc.

Hope this helps!

Steffi Kautz & the AntAsk Team

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