September 2013 Archives

Do Ants have hearts?


I know ants don't have true hearts or bloodvessels but how do they push things around their bodies? Where is the "pump" located?

Thanks
Lynn

Dear Lynn,

Ant, like all other insects, do not have an arteries or vein system, but they do have an open circular system. Their blood is called haemolymph, it is almost colorless and it does contain only 10 % blood cells, most of its volume is plasma. This haemolymph is used for the transport of hormones, nutrients and metabolic products, but not for the exchange of oxygen and carbon dioxide.

To enable the circulation of this haemolymph, ants have a very simple heart which is located at the abdomen of ants. Their hearth is like an arteria which is surrounded by some small muscles. When this heart contacts by these muscles (going from the back to the head), the haemolymph is pressed into the different body parts, a significant part is directed to the head of the ant. Insects may also increase their haemolymph circulation by pressing their abdominal parts.

For their oxygen supply, they have small openings called spiracles at each body segment which supply their body directly with fresh air. When the oxygen enters the body, it goes via tracheal trunks and the smaller tracheal tubes to the different body parts and organs. As this system works mostly by passive air exchange, the body size of insects is limited to the dimension we know, so huge monster insects know from certain movies could not exist as they simply could not breathe.

Thank you for contacting us at Antblog!

Dirk Mezger & the AntAsk Team

Today, my husband and I were walking out of our house in a small town in Ontario, Canada near our capital city, Ottawa.... And suddenly, our entire concrete patio out front was COVERED in these tiny golden colored ants, and many flying ants that weren't yet able to fly it seemed - the bigger flying/winged ones, looked more like black ants with wings. There were what looked like thousands, no exaggeration.... And neither of us had ever seen a single one before this. They were also covering a certain vine like plant on either side of our garden, but primarily, seemed to be on the concrete??

Very strange! Just curious if you may have any idea what these may be, why they'd suddenly be infesting my front patio, if they are a danger of any kind to us or our animals, and finally, how to avoid them!

Thank you very kindly,
Kristin


Hi Kristin,

We have contacted another expert, James Glasier. James is Antweb's curator for Ants of Alberta. Here is his response to your question:

"Hi Kristin,
From your description it sounds like you saw Lasius ants (sometimes called field or meadow ants, though common names vary) initiating their nuptial flight. Nuptial flights are when winged males and females of a colony fly up into the air, mate, and then found new colonies. Lasius queens are often a lot larger and can be a darker (often black or brown) compared to their worker caste, which are often light brown to amber in colour. Many Lasius species spend most of their time below ground, farming aphids and other insects on the roots of plants; milking them for a sugary substance called honeydew, which the ants eat. Often the only time you see them is when they are mistakenly dug up or are having their nuptial flight, so you were lucky to see and experience this event. Lasius ants present no danger to you or other animals; in fact they are an important food source this time of year for migrating birds and bats. Thank you for you question!
James Glasier, MSc, PhD Candidate UNSW in Invertebrate Ecology"

I hope this helps,
Steffi Kautz & the AntAsk Team

Hello,

I briefly perused your blog and found it most interesting and informative. I have a question (similar to this one) regarding how ants deal with dead ants. Your answer is along the same lines of what I read in a published paper. I haven't had a chance to find it again. In that paper, the researchers cited the same reasons - nest hygiene. They further went on to state observations that ants will dispose of the dead at least 10" away from the nest entrance ('graveyard') and ignore dead ants outside the 'clean' perimeter.

I've had several invasions in our kitchen and have observed contradicting evidence. The closest a nest can be is several feet away if not more (definitely not 10"). After I have killed ants in the kitchen (a diluted solution of Dawn dish soap works well), more ants came which I killed. During the few minutes/hours I was able to sleep the ants carried away the dead. More ants came which I killed, and more dead were carried away. This went back and forth for about a week, but then one day, they had managed to remove all the dead ants and the invasion stopped. It appears the repeated incursions were to retrieve the dead ants versus scouting/invading.

I have observed this behavior at least three other times spaced out weeks to months apart. From my observations, the theory that removal of the dead is for nest hygiene does not apply. This is more reminiscent of 'no soldier left behind'.

I would very much welcome your thoughts on this. If I find the article I mentioned, I will send you the citation. There may have even been one or two more articles but my memory fails me.

Than you for your time and attention.
Gary


Hi Gary,

Thanks for contacting us and describing what you have been observing! This is indeed very interesting. There are more than 14,000 ant species and they are not all the same. However, from all the ants that I have observed, I have never seen that ants eat their dead nest mates. In your particular case I do even more believe that the ants were not after their nest mates for food as you used detergent to kill them. I don't believe ants would eat detergent. If eating is not an option, I would again suggest that they bring them to a grave yard. Maybe they considered your kitchen as part of their territory and wanted to keep it clean. Let me know if you (or anyone else) have any other ideas why the ants were removing the dead bodies. I'd love to hear your thoughts on this.

All the best,
Steffi Kautz & the AntAsk Team


Hi AntAsk,

Your hypothesis that the ants consider the kitchen part of their territory is very intriguing and quite possible if ants do extend their territory in such a manner. I do know that there are very large nests around, and probaby under, the house. I have also observed this behavior of retrieving the dead outside as well. One night there are hundreds of dead ants (killed with Raid) and the next day they were all gone. This happened several times also. Wind, rain, etc is not a factor and I'm not aware of any other insects that would carry away or eat ants. And I know there are no anteaters around here lol (I'm a UC Irvine alumni and our mascot is Peter the anteater!).

Thanks!
Gary


Hi Gary,

Thanks for getting back to us! This is quite an interesting observation and not having observed this behavior myself, it is challenging to come up with additional ideas. I find it particularly striking that the ants do not avoid other ants that had been sprayed with Raid.

All the best,
Steffi Kautz & the AntAsk Team



Ants and water


Hi AntBlog,

Do ants need water in their nests? And, if so, how do they get it there? I assume individual ants need water - the commonly held belief that ants come in kitchens for water - is that true?

Thanks,
Natasha


Hi Natasha,

Thanks for contacting us at AntBlog.

As any organisms ants do indeed need water. Their need for water is higher when humidity is low, for example in desert regions or during hot and dry summer months. Individual workers will take up water and then transport it to their nest. Ants have a crop, a so-called "social stomach". They can use this stomach to store food and liquids and then regurgitate it when they need to share it. This is a very common mechanism by which ants feed the brood of the colony. Sometimes food is also shared among workers, different adult members of the colony. This "mouth-to-mouth feeding" is called trophallaxis.

To answer the second part of your question, during very dry weeks ants may indeed come into a kitchen because they are attracted by water. More commonly though ants come into kitchens because food is left out and they are attracted by food. Often, ants are attracted to sweet foods, which are left out. We have a general post on how to get rid of ants in your house here.

I hope this helps,
Steffi Kautz & the AntAsk Team



Ants in organic gardening


Dear AntWeb,

I am curious about ants and I'd like to know If they (like Formica rufa) have potential to keep caterpillars or other "pest" away from cultivated vegetables. I guess yes, though there must be some difficulties to move the ant hill from one place to another, it might be restricted by laws or the ants might not like the new place as is. If it is possible to move them, or there is a way to do so, please tell.

Thank you your answer in advance,
Ferenc


Dear Ferenc,

Thanks for contacting us!

Generally, we highly encourage organic gardening and think it's a great idea to pursue your gardening projects without any artificial pesticides. However, I do not suggest moving an ant colony closer to your garden to help them fend off caterpillars. You are absolutely right that ants can provide a defense for plants as they might chase off herbivores either by preying on them or through there mere presence. This may or may not work depending on the ant species you find and how well they are recruited to your plants. The ant colony might also just not make the transfer and you did all the work for nothing. Also, the opposite of a positive effect for your garden might happen. Ants often herd aphids in order to feed on the honeydew that these herbivores secrete. This might then introduce a problem with aphids in your garden. Instead, I would just remove caterpillars manually or improve the quality of your backyard for natural predators such as birds. Setting up some nest boxes might help already! Birds consume high numbers of caterpillars - in particular if they are feeding their offspring. There is also an organic pesticide that you can make yourself. You just place stinging nettles in a big barrel and top it off with water. It takes about a week and you'll have an effective tincture against all sorts of herbivorous insects. You can spray this on your plants and there won't be any negative effects. Beware though as the smell might not be pleasant.

I hope this helps and good luck with your project!
Steffi Kautz & the AntAsk Team


I found a few if these insects in my yard the other day. At first I thought they were red ants, but in trying to identify them in line, I am now wondering if they are some sort of wingless wasp ant mimic. I have look long and hard to try to identify the type if insect I'm dealing with here and am coming up without any answers. Can you please help me ID this interesting insect for me? There is a black carpenter ant in a few of the photos just for comparison. Thacker you VERY much for your help!!!

Meredith
image(1).jpeg

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Dear Meredith:

Thanks for sending your pictures of this interesting ant to the Ant Blog. These are recently flown queens of one of the citronella ants, Lasius latipes. Your difficulty in tracking them down stems from the fact that most ant pictures online are of worker ants, which in this case look very different from the queens. The unusual morphology of these insects is related to their mode of colony foundation. Rather than raising her first brood of workers alone, a queen of this species barges into a colony of a host species, another member of the same ant genus called Lasius neoniger, kills the host queen, and if all goes well, becomes accepted by the remaining workers, who help her raise her first brood. For a short while a colony containing workers of both species ensues, but eventually a pure colony of the well-armored queen and her pale orange-yellow workers results.

Parasitism of this sort is relatively common among ants, including several other species in New England, in the genus Lasius, and also in Formica, Myrmica, Tapinoma and Nylanderia. It used to be though quite rare in the Tropics, but recent exploration of the ant faunas of tropical areas are revealing many variation on this theme in those regions as well.

Regards,
James C. Trager & the Ask Ant Team

Hello!

I have one to two colonies of small black ants living in the outside bricks and walls of my home. I live on the West Coast of British Columbia in Vancouver and they appear every spring and last all summer. they are very industrious and I hate to disturb them or kill them if they are not causing damage to my home... can you please tell me if I should be concerned? Or should I just let them be? I admire them.

Paula
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Dear Paula,

Thank you for contacting AntBlog and we are glad to hear that you have been watching and appreciating the ants around your home. Most ants are not problems and are in fact good to have around. From your description it does not sound like you have anything to worry about. Below are two previous posts you may find informative. One about the importance of ants in the environment and one on how to get rid of ants in your home should you decide later that they are becoming pests.

http://www.antweb.org/antblog/2012/08/what-good-are-ants-david-panama-city-florida-usa.html

http://www.antweb.org/antblog/2010/07/help-i-have-ants-in-my-home-and-want-them-out-oscar-oakland-ca-usa.html

Best regards,
Corrie Moreau & the AntAsk Team