That's interesting gnampie! Questions:

1) Do the new queens replace the old ones, and rule the colony when the old ones die?
2) How long do the queens live for anyway?
3) How do the ants mate - like...er...normal animal style, or do the males just fertilise the eggs like fish do?
4) What's the lifespan of worker ants?
5) What's the difference between worker ants and soldier ants?
6) How can the worker ants have offspings when they're sterile?

[Edited on 5/3/2002 by Ungoliant]

I don't kill ants or spiders out of hand; only if they become a nuisence. Haven't firebombed an ant hill for fifty years. But I do eat dead cow, chicken, and pig; however, I draw the line at horse, dog, and human.

When I left the forum yesterday there was no question 6 yet. Here is the answer:

The ovaries of the workers do not develop because the reproductive ants use pheromones (chemical substances) to prevent that. In some species this is reversable. When you take the queens away, the ovaries of the workers will start to develop. When the ovaries are functional the workers can start to reproduce males (because they develop out of unfertilised eggs). There will be a lot of fighting between the workers and the dominant ones will be able to mate. In this case, when a worker is able to mate and can reproduce both female and male ants, the worker is called a gamergate (there are often more than one in one colony). This gamergate produces those chemical substances again to controle the development of the other workers ovaries.
So now you can ask the question why do the workers stay in that colony in stead of walking out and start one of their own. Well they have 75% (if the queen or gamergate mate with only one male) of their genetic material in common with their sisters and only 50% with their own offspring. So to make sure their genes will survive it is better for them to stay in the colony and take care of the eggs of their mother then to produce eggs of their own. Of course when there are several queens or gamergates which mated with more than one male the relatedness between the sisters will be less than 75%. This will lead to a lot of tention in the colony so there is a need for other contole mechanisms (like chemical substances). But there are lots of theories and a lot of research about this topic.

Well, I don't know about Australian bull-ants, but they always told me the sting of fire-ants is one of the worst.
If I remember well, African Soldier ants don't sting but bite. At the lab where I worked they told me if a moving colony of those ants comes across a sick small cow or goat they would kill it and eat it. But maybe that is a bit exaggerated.

Well, I'm unmasked!
The ants we studied are called Gnamptogenys. We named them 'the Gnampies'. So it's kind of a nickname.

Thanks for the wonderful clarification Gnampie. Boy the world is a lot more complex now than when I went to school.

We had a fire-ant outbreak in Sydney recently. The postAuthorIDities were frantically trying to destroy them all before they spread. I had no idea they could bite / sting.

Did anyone hear if they killed them all or not? Hope I dont find them in my backyard if they can sting worse than bull-ants!

Oh, ok then. I don't think they're the Solenopsis invicta though since they nest in trees, not on the ground. And I did squeeze several, that must be why more ants kept coming to our campsite.

Whats the best way to kill fire ants - douse their hill in gasoline and set on fire or blow up the ant hill with tnt?

Ah, anticide, a sad & touchy topic!
But that's it... I'm now fairly habituated that every time we speak about ants, sooner or later it comes to it.
I once participated in a radio talk on ants and had , among other, to answer phone calls about them. And I had a call from a lady who had great problems with the common small black ant Lasius niger. She told me that she tried to use a wide spectre of ant killing methods, among others, pouring boiling water into their nests.
It sounds like a horrible cruelty, but, actually, killing insects (and other small invertebrates) with boiling water is recommended as one of the most humane methods of their killing. Another recommended method is to freeze them alive. It was even sort of proved that ants subjected to freezing alive do not suffer. If they are put to sleep with carbon dioxide, they are stressed: we know that because if we analyse chemical substances left by them on the walls of the container in which they were kept, we usually find plenty of alarm pheromones which means that they WERE alarmed, to the degree that they tried to summon their nestmates. In contrast, if you are freezing them alive, they just calmly fall asleep and they do not release alarm pheromones.
It is counterintuitive, but squeezing is NOT really a good method! It is very difficult to destroy the head and the brain (it's very hard) and a head separated from the rest of the body can live on during quite a long while... hours...
So returning to the lady who had black ant problem, I was quite sympathetic when listening to her story and in particular I did NOT brand her as a cruel monster (she was not!).
Unfortunately, that radio talk was heard by my two elderly colleagues who get very indignant about it and then on a scientific meeting they said (very seriously) that they must report a great shame: one of their colleagues (they won't even mention the name... it's so shameful!...) publicly recommended cruelty to animals in a radio talk!!!!
"PLease name some animal" they told accusatingly to the audience. "Horse" said one of the persons present on that meeting. "Well, what would you think about a person who during a radio talk listens calmly when somebody is telling that he ws trying to kill a horse by pouring boiling water on it? Can you imagine that that person said nothing to brand that abominable cruelty?".
You can imagine how I felt, I really didn't know whether to laugh wildly or to take the matter seriously and try to explain all... Finally I decided that the whole situation is so grotesque that it's better not to answer in any way. I only hope that these two ant lovers will never ever read this Forum because your stories of gasoline and dynamite would shock them even more!!!

Alyssa,
How sad to hear that you have such problems with bull ants that your father is a bull ant hater! I am a bull ant lover and I'd give a lot to have a bull ant colony and to be able to study them. It's may secret dream since a long time - but Australia is so far away...
Bull ants are fierce and dangerous, but they are without any doubt the most interesting ants I worked with. I had once a small colony of the large bull ant Myrmecia nigriceps where each of 20 individuals was marked individually and I could follow their behaviour on individual level. It was simply fascinating. Each ant was different!
And they are the only ants which can make an eye contact with the observer! It is really uncanny to see a bull ant guarding the entrance of its atrificial nest and actually LOOKING YOU in the eyes!

Eryan,

Bulldog ants can look at you? I will check that out next time I encounter one, although strangely I don't know the location of any nests. Sure I could find one in the local reserve though.

Sorry if we seem barbaric to you with killing methods - but with young children running around, sometimes we have to take drastic preventitive action. I dont think the speicies is in any danger of extincion though!

Well, how to kill or get ridd of ants was one of the first questions I expected to get. I was very happy we got some other questions first.

I don't like the idea of killing ants either, but I guess there is a difference between just killing them because they annoy you or killing ants as a form of pest controle. But if we must destroy an ant hill we might as well choose a less painful way. When you destroy a colony, you always have to make sure you get the queen(s) and the eggs as well.

But try to let them live if you can. They are really usefull.

So, anything else you want to know?

I personally (being a gardener at heart - but not having the ability to practice for 2 years now... but you should have seen my garden 3 years ago! sigh) like ants, they kill destructive bugs and keep them at bay - but Fire ants are just too aggressive. I can't manage with them. They leave long lasting bites and allergic reactions here in Texas are getting more and more common. We had introdduced here a fly that lays it's eggs on fire ants and the larva eats them up (or something like that). This has helped keep the fire ant population from exploding, but I bet you have no idea how MANY fire ants there are here... it's incredible.

Eryan, thank you for the more detailed explanation. Glad to have you around to help me out. My knowledge of ants is a bit rudimentary. I will learn a lot here. Workers that can reproduce other workers out of unfertilised eggs? How do they do that? Are these new workers not diplo’d then?

I'm not too keen on ants either, I'm afraid. But I only kill them when they come into the house, cos they tend to stay in and reproduce. (which I'm not very fond of)

Only you need a microscope to see it properly. :P

No Tommy, a microscope would be too smallifying, just like the Hubble Space Telescope would be to largefying. What is needed is a maggot-frying lens and a little direct sunlight. :angel :grin

No Grondy, you promised to be kinder to our many legged little friends, so make that diffuse sunlight. :boring

Ants are really fascinating and sweet if you know how to tell what is their "mood" from their movements and postures. They have not facial muscles - they are imprisoned in their exosceletons like knights in their armour - so they seem to uninitiated humans to be like robots, like lifeless zombies. But they signal very clearly whta goes on inside them by postures and by movements. An angry ant is opening its mandibles in a threatening way and curves her abdomen forward, like a dog thrusting his tail between his legs, ready to sting the opponent or to spray it with the formic acid. A submissive ant withdraws backwards its antennae and makes herself as small and as flat as possible... A hungry ant can beg for food in really expressive way, stimulating her nestmates with antennae and forelegs...

Plastic, I have no idea what you are talking about!
What is phase IV?

It's a really great sci-fi movie about an ant research lab, where the ants kill pretty much everybody by evolving quicker than the Borg.

Ants. Not a subject I expected to find on a Tolkien forum, but interesting nonetheless. Thanks Gnampie, Eryan.

I can understand how in a haplo/diploid colony the altruistic behaviour of the female workers comes about because as you say, they are more closely related to their sisters than to their own offspring. This doesn't explain why Termites exhibit the same altruistic behaviour, however. Having a permenant king within the colony, they are not haplo/diploid (or am I wrong here?) What mechanism do they have to keep the colony together?

Thanks for your interest Valedhelgwath!
The haplo/diploid-rule goes (in general) for all social insects, like ants, bees and termites.

Tommy, I think Microcosmos is a French movie.
I liked the way they showed how big small things can be for little insects, like raindrops.
Most people see insects like something creepy, dirty and insignificant, but have you ever tried to imagine how it must be like being an ant or a bee or a beetle? It's like a book actualy, you only have to imagine entering an other world. Life is fasinating!

Oops, sorry *blushing very deeply*
I forgot termites are Isoptera and not Hymenoptera *trying to save me with some expensive words*

Thanks Eryan for correcting my mistake.
Where would I be without you.

Well Thank you Tom for your faith in me! :0:

Valedhelgwath, I suggest you wear your abestos underwear for a while, I expect Eryan to fire up her flame thrower and come after you. She is an ant admirer and I don't believe she likes to hear of her friends being tortured.

(I'm the one who used to firebomb ant nests fifty years ago, but soon learned the folly of my actions, and haven't knowingly harmed any in the last four decades.)

Valedhelgwath (can't I just call you Val, much shorter to write), I only studied ants for a very short time so I am no expert about this and I even know less about termites, but I searched the internet a bit and this is what I found till now:

Accoring to Krebs and Davies (1993) there are two main reasons for the altruistic behaviour of termites:
1) cycles of inbreeding (mother - son or brother - sister) and outbreeding: this mechanism could lead to higher levels of relatedness, even higher as the 0.75
2) a high degree of linkage to sex chromosomes
(Krebs & Davies (1993). An introduction to behavioral ecology, 3rd ed. Blackwell Science)

According to others altruistic behaviour in termites occures due to self interest: the action benifits the individual and the group or workers turn group behaviour to their individual adventage, food, defence, nest building. After all their relatedness with their sisters (0.5) is as high as with their own offspring (0.5), because there is only one queen and one king. This is also related with a higher inclusive fitness, which is the individual fitness plus the fitness of the related individuals multiplied with the degree of relatedness.

The altruism of the workers can also exsist due to parental manipulation by the queen and king, often by means of pheromones given to the workers through trophallaxis (exchange of food).

I also found something about micro-symbiont charing: essential digestive components may only be available through direct transfer from parent to offspring after birth. This is true in the termites, whose young obtain cellulose-digesting bacteria from their parents through oral or proctodeal feeding. In other words, families must remain together for at least two overlapping generations.

That's all for now. If I find anything more, I will let you know.

And Plastic, leave those poor little animals alone for once!
It's no fair battle, such a small animal against such a big guy.