Ants That Can Count

thisIsOdd writes "NPR had a recent report about scientists at the University of Ulm who suggest that ants in desert environments count to help them get to and from their homes. Because the desert's windiness and sandiness is not conducive the 'smell-trail' method, where ants squeeze certain glands that leave a chemical trail, scientists were puzzled by the fact that these desert ants were able to leave and successfully return to their nest. The theory is called the 'pedometer theory,' and the experiment used to test it involves manipulating the leg length of some of these ants. Ants with longer legs would pass the nest on the way home, and ones with shorter legs came up... well... short."

Comments

This doesn't prove ants can count

[ls671]

If the experience results are valid, there is still a difference between counting and remembering and reproducing a sequence of movements.

Ants might remember that they have to do "step step step step step step step step" to get back to their nest without actually counting. This would seem much more natural to me.

Here is an example applicable to humans: As a drummer, I can create and reproduce the same roll on the fly. But if you asked me how many times I hit the drum pad, only then I would have to count. I did not need to count in order to reproduce the roll nor did I know how many times I actually hit the drum pads.

This leads me to believe ants cannot count, why would they need to. Counting is good for humans in order to trade, so they have developed that capability. Same goes for female animals that could notice one of their puppy is missing. They don't have to "count" them, they only have to remember a picture of all the puppies and notice the picture they now see is different from the normal picture. There is many more examples you can think off where one can appear to count without actually doing so.

Re:This doesn't prove ants can count

[tonycheese]

While you may be right, the examples you gave don't necessarily extend well to the ants. An animal looking for its babies would see less than 10 or 20 and reproducing a roll on your drum would involve varied rhythms or beats or whatever, or probably less than 50 hits if you were to reproduce it after hearing it once. The ants, however, are probably taking hundreds or thousands of steps and remembering the exact distance in one go. I cannot imagine a person hearing a roll go for 750 hits and then reproduce it in the same ballpark without counting time or hits (but I'm no drummer). The article described it as a "pedometer" and I think describing it as counting is perfectly valid - being able to distinguish between 1200 and 1300 steps would involve some form of "counting" in my mind, whether in the brain or by some physical mechanism.

Re:This doesn't prove ants can count

[Psaakyrn]

It still works. Drummers don't just drum for a single lyric, they drum for the whole song. The ants are just playing an orchestra of beats.

Re:This doesn't prove ants can count

[njen]

But if the number of hits in a roll was dependent on you finding your home safely, then I am pretty sure you would be counting it. The ants are not relying on a random number of steps to find their way home, like in your drum analogy. Plus you can't be certain without counting that if asked to reproduce a roll of the same number of hits that it would be the same number of hits. It seems these ants do rely on walking the exact same number of steps each time.
This would denote that the ants have memorised a number of steps to take that would allow them to return home again, thus showing that when they have counted a certain number of steps would allow them to know where they are.

Re:This doesn't prove ants can count

[MartinSchou]

As a drummer, I can create and reproduce the same roll on the fly. But if you asked me how many times I hit the drum pad, only then I would have to count

Been quite a while since I played drums, but I still remember having to learn how to reproduce certain sequences, and that involved counting the number of repetitions.

I can't remember what it's called but the one where you emphasise every third hit (i.e. HIT, hit, hit, HIT, hit, hit etc) came quite fast, and I can still do that one without even trying (including alternating between 2nd, 3rd and 4th). The one that has every fifth hit (HIT, hit, hit, hit, hit, HIT, hit, hit, hit, hit) is one I never got the hang of, and I remember spending a LOT of time trying to burn it into my muscle memory.

But the 3rd one, while easy, still required learning by counting "ONE, two, three, ONE, two, three" for quite a while.

My point is, when you get really really good at something, like drumming, you don't count at a concious level, but in order to get that good, you did need to count.

Re:This doesn't prove ants can count

[discbrain]

If you would have read the article (I didn't read it, but I'm from uulm and am familiar with the corresponding research results) or the referenced research, you would know that all what you stated is obviously taken account for. For example your "they only have to remember a picture of all the puppies and notices the picture"-statement is wrong because of the following experiment: An ant is taken from its current location and moved to another location some meters away. So the ant has no way to tell where it is located at, but it still runs the straight way "home" (though ending not at the ant colony but somewhere else)...

Re:This doesn't prove ants can count

[ls671]

What I was trying to say is that counting usually involves numbers. You could build a car engine (or do almost anything) without using numbers. Instead of knowing the clearance for a given part is say 11mm, you could just use a mark on blank ruler or other tool the find out the right clearance. I suspect something similar is going on with the ants.

Also, I am glad you specified that you were no drummer. Drummers can reproduce songs with thousands of hits on the drum pads over and over again without counting. Don't let the drummer counting "1-2-3" at the beginning of a song fool you. He could as well go "Pom, pom, pom" and it would work as well.

Re:This doesn't prove ants can count

[ebuck]

Math isn't just about a bunch of numbers. Push down automata can count (I know, it's incredible! Even more so considering they have no fingers) The program as I heard it basically described a behaviour which could easily be simulated via a push down automata.

As a drummer, you might be so accustomed to a particular rhythm that you don't count it out in the literal sense of counting out loud, but you do put eight strikes into a measure. Whether you acknowledge that as counting or not, it is still counting, it is just counting that you have become so accustomed to that you don't consider it counting because you need to reframe it in a different context before you can acknowledge to yourself that you are counting.

Rather than using your own logic to falsify the scientist's hypothesis, perhaps you should have listened to the details of the experiment and observed the results. You might have found a superior but alternate explanation, in which case you would have expanded the realm of possibilities a bit. You might even be able to suggest a follow up experiment to differentiate between the counting hypothesis and your alternative to determine which is more correct.

I take it that you haven't done much with functional programming languages, as there are often certain types of problems that are more easily solved in functional languages by counting in the manner of "one one one one one" (as five) than by actually storing a five.

And while I'm at it, trade doesn't require counting. Bartering might involve counting, or it might simply be a swap of my fishtank for your LP collection. However, the idea that we knew counting would be good for trade so we developed counting is a cunning bit of mental gymnastics; it's the mental equivalent of putting the cart before the horse.

Re:This doesn't prove ants can count

[Psaakyrn]

If the ant has no way to tell where it's located at, how can it run the straight way "home"? Hence the ant knows exactly where "home" it, it just correlates the distance with the steps it needs to take. But that correlation can still be done via rhythm as opposed to actual numbers. (like trying to judge what tune to play to fir into a 60 second time-frame.

Re:This doesn't prove ants can count

[Hurricane78]

Uuum... What you describe IS counting.

It’s astonishing to what lengths people go, to preserve their arrogant world view of “superiority”.
A hundred years ago, common “knowledge” was, that animals don’t “think” and have no “souls” or “emotions”. They thought they simply simulate it and are in fact basic automatons.

Well, nowadays we know, that we are basic automatons too. That thinking and emotions are merely mechanisms. And that there is no “soul”, nor a need for something like that.

Let’s play this game: I say: You simulate thinking too. Including counting! And I will your method of argumentation to defend it.
And you will try to prove that you really think and can count.
You will notice that as long as you play by my rules, you can’t win. ^^

Re:This doesn't prove ants can count

[ls671]

> "It seems these ants do rely on walking the exact same number of steps each time. "

I don't think so, I figure the ants are smart enough to find the nest when they are only a few steps away from it. Also, see my above example on drummers playing whole songs without counting. Counting is typically human and gets in a way when you play music, you only count when you are beginning and learning to play. Who knows ? Counting might be a very primitive behavior after all. If more intelligent life forms exist, maybe they don't need to count (i.e. use numbers) ;-))) Think of it, maybe humans count because their brain isn't sophisticated enough to remember quantities otherwise.

I am over doing it quit a bit but then again who knows ? ;-)))

Re:This doesn't prove ants can count

[Psaakyrn]

It's still not counting, though it can reproduce the effects. A calculator doesn't actually count (it's just bit switching), but it reproduces the effect. Granted it means that whatever it's doing can simulate the effect of basic counting, but it in no way represents the understanding of numbers, which would be the implication of counting.

Re:This doesn't prove ants can count

[discbrain]

Say, for example, the ant is about 45m away from its base, and to replace it somewhere else, the ant will nevertheless run about 45m (and afterwards, if it can't find its colony, it will start with search-patterns). You won't be able to accomplish this with rhythm only.

Re:This doesn't prove ants can count

[hazem]

If the ant has no way to tell where it's located at, how can it run the straight way "home"? Hence the ant knows exactly where "home" is

Some ants use a type of sense of smell to know where they've been (if they leave a chemical trail) and where the nest is. I expect the scent from the nest diffuses in the environment, so they just have to head "uphill" in the scent gradient to get to the nest. This, at least, is how I've seen ant simulations programmed.

I don't know how this applies to the experiments here, since the ants with extra long legs went past the nest. It could be that there aren't enough ants in the nest to produce a strong enough scent gradient.

The idea that they can count is interesting. However, I wonder what happens when the ants must take different routes too and from the nest. I wonder what would happen in these experiments if for some of the ants they increase the distance to the nest without actually altering the ants themselves.

Re:This doesn't prove ants can count

[Anonymous Coward]

in before "accidentally the whole $something"

Re:This doesn't prove ants can count

[4D6963]

No, you misread, he said that when you move an ant, they act like they haven't been moved. They don't get home, they go where they think home is without taking into account the offset taken when they were moved, which means they're blindly walking back with no regard for environmental clues.

Re:This doesn't prove ants can count

[hazem]

It's still not counting, though it can reproduce the effects. A calculator doesn't actually count (it's just bit switching), but it reproduces the effect. Granted it means that whatever it's doing can simulate the effect of basic counting, but it in no way represents the understanding of numbers

Well, this is science. These researchers had a hypothesis that ants can count and devised an experiment to test the hypothesis. Based on their assumptions, the evidence from the experiments support their hypothesis.

Your hypothesis is that it's not counting but something else. It seems the next step is for you to devise a way to isolate counting from doing a counting-like behavior in ants and do an experiment to test your hypothesis.

However in a way, you're just playing with the definition. What does "understanding of numbers" mean? And is it really integral to counting? If you use pacecounter beads (Ranger beads: http://www.instructables.com/id/Army-Ranger-Beads/), you are "counting" on a piece of string but not actually keeping numbers in your head. In fact, the whole point of those is that you don't have to keep track of numbers because it's hard to do when you're exhausted and have all the other soldier-things to keep track of. You could use these beads to go out some distance, turn around and come back the same distance. You wouldn't have to use numbers in your head, but counting is still being done.

Re:This doesn't prove ants can count

[timmarhy]

there is no difference between subconsiously counting the beats and consiously doing it - it's still counting the beats. your confusing counting with mroe complex MATHS, which as far as we know ants can't do.

Re:This doesn't prove ants can count

[lastgoodnickname]

Can't beat a drum analogy

Re:This doesn't prove ants can count

[noidentity]

What next, you'll be saying that a child who catches a ball thrown by the parent isn't doing quadratics in his head, or that a child recognizing a pitch of sound isn't doing a fourier analysis in his head. Pshaw!

But really, as you say, there are many ways to implement "don't walk past the home nest" than counting the number of ant steps. Assuming a consistent pace, walking for some amount of time would do, or walking until you get run down a certain amount, etc. Once near the nest, there are presumably other markers to help home in.

Re:This doesn't prove ants can count

[lastgoodnickname]

some do, some don't

Re:This doesn't prove ants can count

[discbrain]

The 'scent-path-or-gradient' doesn't apply here because it's too hot in the sahara for a scent to last long. additionally, there aren't that many ants out there to produce enough scent - they would get burned rather fast (this, for example, is the reason why those colonies only send the old ants to collect food). Furthermore, the region one ant scans for food is rather huge (the move really fast, otherwise they 'would burn their feet')... For more information on the ants google for Cataglyphis.

Re:This doesn't prove ants can count

[HybridJeff]

The way I see it even though you aren't consciously thinking of the number of drum beats as they pass by, you are still perceiving that number of beats and keeping track of it somewhere in your sub conscious. You may not use the same system to count, but I would argue that any method which is used to keep track of an incrementally increasing value even when not specifically defined as a number is a form of counting.

Music is probably the most common form of sub conscious counting we have, what is counting if not pattern recognition? When counting a series of number all you're really doing is keeping track of your position in an already recognized pattern and then continuing that pattern when you reach a number you have never used before. The same thing happens when you repeat a song that you know from memory, keeping your position in the music-space of a song is akin to keeping your position in given number space while counting. Were just aware of it in different ways.

Back on topic, I don't the ants are consciously thinking one... two ... three in their minds as they walk (I doubt they have a stream of consciousness to the same degree that we do) but that doesn't mean they don't have some instinctive ability to keep track of their progress through a pattern. If it effectively does the same thing as counting then we might as well call it the same thing.

Re:This doesn't prove ants can count

[Anonymous Coward]

what TFA does not tell, is how the ants will communicate the location of the food source to their little friends.

I myself have an alternate theory, and that is they can track relative time (maybe with their 'pedometers', counting off seconds) but they also can track the sun and its position in the sky with regards to their nest. Here's a video by sir David Attenborough explaining it: http://www.youtube.com/watch?v=46noJXIrdVg&feature=player_embedded

Re:This doesn't prove ants can count

[SolitaryMan]

The GP's argument that it CAN be done without counting is still valid, as he provided himself as a counter-example.

Re:This doesn't prove ants can count

[TropicalCoder]

Drummers can reproduce songs with thousands of hits on the drum pads over and over again without counting.

Only because they are guided by the music perhaps, but you gave me an interesting idea. Imagine the music as a metaphor for the scenery passing by as you journey from point A to point B. In fact, imagine you are a little ant listening to the beat of your six little feet as the landscape rolls by... Passing through this little valley took so long, climbing up that hill the rhythm changed, and running down the other side was yet another rhythm for a different duration. Now imagine someone cut your legs off at the knees... Oh what cruelty!

Re:This doesn't prove ants can count

[molecular]

If it _appears_ to be counting, it counts.

Simple as that, the interna don't matter, just the outside effect.

Re:This doesn't prove ants can count

[TropicalCoder]

As a drummer, I can create and reproduce the same roll on the fly. But if you asked me how many times I hit the drum pad, only then I would have to count. I did not need to count in order to reproduce the roll nor did I know how many times I actually hit the drum pads.

...and if while you weren't looking somebody switched your drum sticks for another set, longer or shorter than you were using, would you play slower or faster accordingly?

Re:This doesn't prove ants can count

[TropicalCoder]

I don't the ants are consciously thinking one... two ... three in their minds as they walk

These six-legged insects count in base 6, of course.

Re:This doesn't prove ants can count

[Anonymous Coward]

I've read about these experiments before, and in my opinion the author of npr.org completely missed the most amazing point: the return way is always going home on a straight line, no matter how zigzag the way to the food was. So the ants don't just count. They are able to add complex numbers in polar coordinates! Try this for yourself!

Re:This doesn't prove ants can count

[soapdog]

so I infer that in Ant School they learn to count and when they become workers/warriors/whatever they start doing it at an unconscious level....

Re:This doesn't prove ants can count

[The Yuckinator]

I just knew it. The drummer isn't counting. They always say that they're counting but here's the proof!

How can you tell a drummer's at the door?
The knocking speeds up.

Re:This doesn't prove ants can count

[Snaller]

And there are a lot of Ant drummers.

Re:This doesn't prove ants can count

[mdwh2]

I admit I'm not a drummer, but I have played other instruments - surely if we're talking about an entire song rather than one bar, the person still has to count lines/bars (e.g., this bit happens 4 times, before going onto the next bit, and these two sections alternate two times)? This would be especially true if the drummer was playing on their own, without being able to rely on listening to the music.

Ants can count. The reason it sounds uncomfortable is because it might imply a comparison to how humans count - we do it using our sentient mind. I doubt that this is the case for ants. But even if it's done by some automatic mechanism, I don't think "counting" is unreasonable (I mean, we say that computers can count, even if it's just following an automatic process that a human set up).

Re:This doesn't prove ants can count

[mdwh2]

What if I write a computer program that recites up to a number that you enter - is that not counting either? What if we have an AI that can count? Where do you draw the line?

I don't think it's a useful definition of "count" to restrict it to entites that have sentience. Do you have a reference for that definition?

Tell me, does a calculator "calculate"? Does a computer "compute"? Or are these also terms reserved for sentient entities that can think?

Re:This doesn't prove ants can count

[Rary]

As a drummer, I can create and reproduce the same roll on the fly. But if you asked me how many times I hit the drum pad, only then I would have to count. I did not need to count in order to reproduce the roll nor did I know how many times I actually hit the drum pads.

If that roll were more than a few seconds long, you would likely have to count. You wouldn't necessarily count the actual individual drum hits, but you would likely count the beats, or the bars, or the seconds, or something.

This leads me to believe ants cannot count, why would they need to.

Well, maybe to be able to travel great distances and then return to where they came from? Much like the theory suggests they are doing.

Counting is good for humans in order to trade, so they have developed that capability.

You misunderstand evolution. Humans have the capability to count, so they have developed trade utilizing that capability. Similarly, ants (theoretically) have the capability to count their steps, so they have developed the ability to travel far from their homes and then return without having a trail to follow back.

Re:This doesn't prove ants can count

[lawpoop]

As a drummer, you might be so accustomed to a particular rhythm that you don't count it out in the literal sense of counting out loud, but you do put eight strikes into a measure. Whether you acknowledge that as counting or not, it is still counting, it is just counting that you have become so accustomed to that you don't consider it counting because you need to reframe it in a different context before you can acknowledge to yourself that you are counting.

I'm skeptical. There could be something else other than enumeration at some level going on. He could be perceiving it more like a frequency on some level.

For instance, I was an exchange student in Finland. I learned to roll my 'r's when speaking Finnish. Years later, I read in a book about learning Finnish that Finns "give three or four flicks of the tongue for a rolled r". Thinking, I said several finished words to myself and realized that I was consistently doing 3 flicks. Nobody had ever told me 'three flicks'; I never consciously noticed it before; I was just imitating the sounds that I heard Finnish people saying -- and some other sounds, such as 'ö' 'y' took a lot of conscious teaching and training. ( And then when I learned Spanish my fellow students made fun of me for going wild with the flicks. )

Anywho, I believe that I perceive, at an unconscious, sound-production level, the 'r' flicks as a time slice of a frequency, rather than a series of individual flicks. Now that doesn't meant that it *isn't* countable, but I don't think that because it is I am *necessarily* using enumeration at some level to create the appropriate 'r' sound.

Anyhow, the drummer may be doing the same things. Frequencies during periods of time, not enumeration.

Re:This doesn't prove ants can count

[Anonymous Coward]

Another theory, that seems equally good to me, is that ants have a good sense of time. They know how long it took to get from the nest to Point A. When they turn around and return, it should take the same amount of time to return. Short-legged ants would cover less ground in the same amount of time and fall short. Long-legged ants would cover more ground and pass the nest.

Re:This doesn't prove ants can count

[cdpage]

I think you both have a valid point here.

A drummer would of course not tell you how many times they hit all their drums, but they also generally have mental markers of sorts along the way in the song to let them know just how far they are.

this could be:
outside markers, such as another instrument playing along / another ant playing its part.
or
inside markers, such as one specific drum in the sequence or they way in which said drum is hit / with 6 legs the ant could be doing one in the same. playing a beat while walking and every now and then one leg does something different giving the ant its markers...

this could be a form of 'counting subconsciously'

Ask a Drummer how many times they hit one drum (the drum they hit the least) in one song, and they likely be able to tell you. as this is likely a marker for them too. but they also never really thought of it before.

Re:This doesn't prove ants can count

[hrimhari]

"Counting" was used as a shortcut meaning "remembering and recognizing the number of steps they take". It certainly doesn't mean going "one, two, three, ... one-million-six-hundred-twenty-one-thousand-seven-hundred-fifty-three! I'm home, yay!" on their head.

Remembering and recognizing a number of anything is still pretty close to counting, wouldn't you say? Especially since the number in question can be the equivalent of exactly 1,621,753 hits to your drum. I'd really love to see you do that exact number of hits without counting.

Re:This doesn't prove ants can count

[ls671]

Sure, I understood that ;-)

This is why I posted about it, this reminds me adds where they misuse words in order to make the product look better than it is in realty and this is what I am against.

I have trained my dog so when I show him a picture of the number "1" he barks once. When I show him a picture of a "2", he barks twice. When I show him a picture of 1+1, he barks twice.

Now, I am going to post my findings on /. pretending that not only can dogs count, but they can also read and perform addition.

Do you work for a publicity agency or are you a politician ? ;-))

It is sometimes amazing to see what scientists will do to sell their findings. This is why I take it with a grain of salt. Many have been found guilty of fraud after their article has been published in very serious scientific papers.

Finally, look up in a dictionary to see what "counting" means and get back to me.

Re:This doesn't prove ants can count

[Anonymous Coward]

Here is an example applicable to humans:

When I read that part of your message - I had to look up your username, half expecting a new addition to the campaign of BadAnalogyGuy and PizzaAnalogyGuy.

You would have made good HumanAnalogyGuy. :)

Re:This doesn't prove ants can count

[ebuck]

A frequency is a count over a span of time. Frequency is a useful measurement, but dividing the count by time doesn't get rid of the fact that it's based on counting.

Re:This doesn't prove ants can count

[MobyDisk]

However in a way, you're just playing with the definition.

It is this kind of "playing with the definition" that really helps science a lot. Suppose we can find another way that ants could do this, without counting. That might give us insight into how their brains and bodies work. That might help us to design smarter chips, or algorithms, or something like that. And when biology and psychology are involved, as is the case here, subtle things like that are actually very useful.

Re:This doesn't prove ants can count

[Anonymous Coward]

One of the insights of computer science is that if you have a well-defined problem and a means of recognizing whether a solution is correct, it doesn't really matter how the solution is produced, and in fact the distinctions that can be formally made between different solution procedures are quite limited. Is what the ants do counting? Do dogs solve differential equations when catching a thrown object? If you seek a strict formal test of whether the ants or dogs solve those two computational problems, the answer is yes. There are differences in the methods they use and the methods an engineer would use for the same problems, but the differences are not so easy to pin down.

Re:This doesn't prove ants can count

[ShiningSomething]

As I understand it, in Math being able to count does not involve numbers, it involves recognizing that two sets have the same cardinality. We do it through the construct of "numbers", but it's not necessary to resort to them. That's how we know that some sets with infinite cardinality have more elements than others.

That's also how we know kids learn to count gradually over time. When they first learn to speak, although they may know the words one, two, three, they only really recognize sets with one and two elements. Anything more is all the same. The number is not the key, the comparison is.

Re:This doesn't prove ants can count

[Anonymous Coward]

I'm not sure how the scientists are so certain that the ants are counting their steps as opposed to simply having a very precise sense of time passing. If they walk at a steady pace, then having a good sense of time passing on their journey would have resulted in the same findings in this experiment...no? Am I missing something? It would seem possible to distinguish between these two possibilities in future research. Maybe I need to read the article.

"manipulating the leg length"

[Anonymous Coward]

Sounds fun!

I felt a pang...

[crioca]

couldn't help imagining what it would be like for one of the ants that had it's legs cut off, was made to walk home across the desert on it's stumps and then was totally bewildered as to where it's home had gone. I know they're just ants, but damn that's sad.

Re:I felt a pang...

[Anonymous Coward]

Ditto.. something about humans and the way they treat life with utter contempt...

Re:I felt a pang...

[Korbeau]

Few ants escape the great finger of God, they should be grateful to get off with only a few scratches!

Re:I felt a pang...

[MarkRose]

I'll, too, admit that the thought of having my limbs chopped makes me a bit antsy...

Re:I felt a pang...

[dirkdodgers]

Many species of ants have elaborate social structures. Ants communicate with one another through touching, chirping, hearing, feeling, and chemical perception. Some species of ants live solely by enslaving other ant species to do their food gathering for them. Ants farm lesser species such as aphids for their excretions.

Don't feel too bad.They'd enslave us and use us for our excretions too if they could. If ants weren't so tiny, we would be at war with them, and they'd be pretty badass foes.

Re:I felt a pang...

[DreamsAreOkToo]

Ditto.. something about humans and the way they treat life with utter contempt...

I could make the same argument about humans. "...something about humans and the way they treat all life as sacred..."

There are very few creatures on the planet that actually react with sadness when something is killed (other than their very close kin)

Re:I felt a pang...

[antifoidulus]

Now that you said that, by slashdot law, I have to post the following:

I for one welcome our new ant overlords!

Re:I felt a pang...

[johncadengo]

From TFA (emphasis mine),

Scientists put stilts on desert ants and discovered that in time, the ants could calculate the correct number of steps it took to get home.

:). TYVM.

Re:I felt a pang...

[4D6963]

Yeah, except they don't have hands and feet, but exoskeletons. They work a bit differently from us. I'm not sure how you can relate to having your exoskeletal legs shortened.

Re:I felt a pang...

[VShael]

I know what you mean.
My first thought reading through the post, was "Oh, maybe they put a sort of treadmill en-route to make the number of steps less than the required amount to reach home" and then I got to the "pull the legs off bit".

I guess I don't have the amorality in me, to make it as a real scientist.

What happened to giants of the community like Feynmann, and the way he treated his ants?

Re:I felt a pang...

[L4t3r4lu5]

It's been bugging me since I read the piece...

Re:I felt a pang...

[molecular]

Now that you said that, by slashdot law, I have to post the following:

I for one welcome our new ant overlords!

and also the obligatory:

In soviet russia, ants cut your legs off.

Re:I felt a pang...

[TropicalCoder]

Almost as bad as the way Schrödinger treated his cat.

Re:I felt a pang...

[Anonymous Coward]

LIES! Its "In Soviet Russia, Ant shortens leg of YOU!" Get the FACTS people!

Re:I felt a pang...

[Anonymous Coward]

Also from TFA (emphasis mine),

The third group had their legs cut off just below the "knees," making each of their six legs shorter.

:). You're welcome.

Re:I felt a pang...

[Sanat]

Lovely Homepage you have there. In spite of what you might believe in this now moment... you are destined for an exciting and interesting life. Thanks you for sharing with us.

Sanat

Re:I felt a pang...

[ebuck]

Good, because they are counting on you!

Somebody has to say it...

[Anonymous Coward]

Ladies and gentlemen, uh, we've just lost the picture, but what we've seen speaks for itself. The Corvair spacecraft has apparently been taken over, 'conquered' if you will, by a master race of giant counting ants. It's difficult to tell from this vantage point whether they will consume the captive Earthmen or merely enslave them. One thing is for certain: there is no stopping them; the ants will soon be here. And I, for one, welcome our new insect overlords. I'd like to remind them as a trusted TV personality, I can be helpful in rounding up others to toil in their underground sugar caves.

Hex, is that you?

[mikelieman]

++?????++ Out of Cheese Error. Redo From Start.

Re:Hex, is that you?

[Korbeau]

Everyone knows ants count in base-8 (six legs + two antennas).

Re:Hex, is that you?

[JerryQ]

Anthill inside

Re:Hex, is that you?

[Gyske]

Given that Hex is even in the tags of the article, I'm quite surprised to read so few Hex-comments. PS Don't know what/who Hex is? http://en.wikipedia.org/wiki/Hex_(Discworld)

pedometer...?

[Anonymous Coward]

really? pedometer?

Re:pedometer...?

[Anonymous Coward]

Unfortunate that the Greek word for child (pais; genitive paidos) and the Latin word for foot (pes; genitive pedis) have both warped into the same prefix: ped-

that accounts for distance...

[gandhi_2]

but not direction. Like doing "dead reckoning" with pace but no azimuth.

Re:that accounts for distance...

[Vaphell]

bees recognize directions by the light polarization - their eyes are able to differentiate polarization which is dependant on angle between the chosen direction and the sun position. Maybe these ants use similar technique.

Re:that accounts for distance...

[fireylord]

It would appear so http://en.wikipedia.org/wiki/Sahara_Desert_ant

Re:that accounts for distance...

[molecular]

TA says: "It's already known that ants use celestial clues to establish the general direction home".
(assuming by azimuth you mean direction)

Re:that accounts for distance...

[dzfoo]

No, no, no! Adding it yourself to Wikipedia does not count!

        -dZ.

Re:that accounts for distance...

[hrimhari]

From TFA:

It's already known that ants use celestial clues to establish the general direction home

Re:that accounts for distance...

[gandhi_2]

Have you ever tried to navigate in the desert using "general direction"?

Re:that accounts for distance...

[gandhi_2]

I read TFA...but have you ever tried to navigate in the desert using "general direction"?

Re:that accounts for distance...

[hrimhari]

Not really. Would it be impairing? I always heard that ants could navigate according to Earth's magnetic field too.

Re:that accounts for distance...

[gandhi_2]

I guess it depends on what they mean by "general direction".

I take it to mean something less than degrees or angular mils...as in cardinal and ordinal direction.

The magnetic field, if it can be read accurately (like a compass), giving the ant fine-grained azimuths..that would work great.

If you go 100 meters and are off by 1 degree, you deviate by about 17 meters. circle/360
If you are off by 1 angular mil, you are off by 1 meter. circle/6400

But circle/8 as in cardinal and ordinal direction...each ordinal has a variation of 45 degrees.

Re:that accounts for distance...

[gandhi_2]

Err....I meant 1000 meters:

If you go 1000 meters and are off by 1 degree, you deviate by about 17 meters. circle/360
If you are off by 1 angular mil, you are off by 1 meter. circle/6400

Just had to do it.

[Psaakyrn]

So, it's like changing the tires of a car to a larger or smaller one then miscounting the distance traveled based on rotations?

Re:Just had to do it.

[molecular]

So, it's like changing the tires of a car to a larger or smaller one then miscounting the distance traveled based on rotations?

A very accurate, yet slashdot-compatible analogy. Congrats!

So did I :(

[Anonymous Coward]

Especially when you think how similar to us ants really are. I mean, when I read:

ants squeeze certain glands that leave a chemical trail

I went "I can do that too!"

Experimental set-up raises a few questions

[jamax]

I'm not being too serious here, but, even though these are just ants, wouldn't it be wrong to assume that I didn't arrive home with my legs cut off beneath the knee because of the resulting leg length?

I mean even though ants a just insects they are really complex mechanisms and there might be some form of damage reaction other than shorter steps after a partial limb loss - like general weakness and reduced desire to go anywhere at all?

Still, desert-roaming ants on stilts (I'm guessing that's how they've increased leg length) sound very much like new overlords we should better bow to ASAP..

Re:Experimental set-up raises a few questions

[amRadioHed]

They said the ants with the short legs took the same number of steps. It would be unlikely that they would get tired or give up at that specific point.

Re:Experimental set-up raises a few questions

[ebuck]

Well, that might be a good explanation for the reason the short legged ants failed to arrive home. However, it doesn't explain why the artificially leg lengthened ants overshot their nest. I mean, if it were you or me, we would have seen our home and stopped, so the ants must really heavily rely on step counting.

Re:Experimental set-up raises a few questions

[silentcoder]

Actually - you raise an interesting point, though I think the other stilt-test discounts it, but I remember reading that insects have neuron clusters on each limb, which respond to stimulus and control them. This is part of how they are able to navigate such complex terrain - dedicated mini-brains on each leg controlling just that leg.
One has to wonder if they made sure not to damage those nerve-clusters.

Re:Experimental set-up raises a few questions

[cpartrid]

Well, that might be a good explanation for the reason the short legged ants failed to arrive home. However, it doesn't explain why the artificially leg lengthened ants overshot their nest. I mean, if it were you or me, we would have seen our home and stopped, so the ants must really heavily rely on step counting.

But the ants were moved so that they would never actually reach there home. So it makes perfect sence that if the Ant got to where he thought the nest was, and it wasn't there he might carry on further. Thus explaining why he overshot. The stilts being irrelevant.

Re:Experimental set-up raises a few questions

[Anonymous Coward]

RTFA, after being placed into the nest the next day all ants found their way back home, the conclusion being that this time they travelled both ways using same-height legs.

Re:Experimental set-up raises a few questions

[Rockoon]

So it makes perfect sence that if the Ant got to where he thought the nest was ...

..and why did he think that?

Re:Experimental set-up raises a few questions

[Rary]

But the ants were moved so that they would never actually reach there home.

Where did you get that idea from? Certainly not the article. Quoting TFA:

The regular ants walked right to the nest and went inside.

The ants on stilts walked right past the nest, stopped and looked around for their home.

The ants on stumps fell short of the nest, stopped and seemed to be searching for their home.

I heard one of the ants in the experiment speaking

[MarkRose]

"Help! Help! I c'ant find my home!" she said.

How many steps before register overflow?

[dirkdodgers]

I can think of a number of follow-on experiments to tell us more about this mechanic.

First I think you'd want to establish more conclusively that it is counting or memory of steps or actions, and not something in the environment:
- Replace the sand behind them on their path and see whether they can still get back.
- Put them on a treadmill to get to their location and back so that their aren't actually moving relative to the earth and see whether they still get back.
- Once this get to the food, rotate the artificial section of ground it is on 180 degrees and see whether they still get back.
- Change the wind direction in an artificial environment and see whether they can still get back.
- Reverse the location of the primary light source in an artificial environment and see whether they can still get back.

Then explore the limits of the counting or action memory mechanism:
- Keep extending the number of steps to get to food until they can't remember how many steps to get back.
- Keep extending the number of steps in a path with a turn in it, on each side of the turn, and compare to the path with no turn.

Re:How many steps before register overflow?

[dzfoo]

I listened to the story yesterday on the radio, and as far as I recall, they implied that the scientists performing the experiment acknowledged that the ants actually took the same number of steps when returning home. This is why they claim that the ants either over- or under-shot their home nest when returning, not just that they stopped somewhere else.

If they actually counted the steps the ants took each way and confirmed them to be the same, then this is significant, and gives more credence to the "pedometer" theory.

          -dZ.

This is oooold news

[TubeSteak]

Science 30 June 2006:
The Ant Odometer: Stepping on Stilts and Stumps
http://www.sciencemag.org/cgi/content/abstract/312/5782/1965

And here's the original /. story from 2006
http://science.slashdot.org/article.pl?sid=06/06/30/006245

Re:This is oooold news

[mbstone]

I can't tell if these crippled ants are the ones from 2006 or the experiment was repeated and they are crippling new ants. At least this time some of the ant legs' lengths are being extended with stilts instead of being truncated. Seems more humane.

Re:This is oooold news

[thePig]

Thank you.
The comments in the old /. article are worth a read.
Esp.
http://science.slashdot.org/comments.pl?sid=189951&cid=15635693
http://science.slashdot.org/comments.pl?sid=189951&cid=15634139
http://science.slashdot.org/comments.pl?sid=189951&cid=15634257

Makes an interesting read. Also, good to have a comparison between the average quality of comments from 06 and 09 in /.

Re:This is oooold news

[JaredOfEuropa]

I can do better than that, I remember reading about counting ants and similar experiments in a popular science magazine when I was a kid. Sorry, no link, as the article predates the Internet...

Re:This is oooold news

[red crab]

Thanks for pointing this out. The first thought that appeared to me after i read this story was that hasn't this already been discussed on Slashdot some time ago?

Re:I heard one of the ants in the experiment speak

[dirkdodgers]

"Help! Help! My leg length has been modified!" she said.

Re:I heard one of the ants in the experiment speak

[MarkRose]

That's got to be awful confounding... I bet the poor thing is stumped!

Re:god, that name!

[Psaakyrn]

And of cause, I then had to figure out what foot fetish would be. Mmmm podophilia....

Sounds like frogs ...

[dltaylor]

To determine how what proportion each leg contributed to a frog's jumping distance, a scientist trained a frog to jump on command. He then measured the distance with all legs, and remeasured after successively removing one leg at a time.

His conclusion: that since the frog, with all legs removed, did not jump after hearing the command, that the frog was now deaf.

Re:Sounds like frogs ...

[L4t3r4lu5]

To think I believed them when they said that crickets had ears on their knees...

that's a rather human-centric definition of count

[booyabazooka]

If you think more abstractly... There's no reason that "counting" has to denote that you mentally encode a number in decimal notation. If you can remember some nontrivial quantity, regardless of what process you use to recall it, I see no reason why you can't call that "counting".

For example, we can say informally that a pushdown automaton has the ability to count, because it can retain some unbounded memory of the number of symbols it has encountered. The information is there, even if you can't directly ask it and get an answer like "613".

I wonder...

[Anonymous Coward]

How do these scientists at the University of Ulm get to and from their homes when the ants are not counting for them?

Does it mean..?

[roman_mir]

But does it mean that they can sort tiny screws in space?

Re:god, that name!

[Antarius]

You're just being PedAntic

Homing in

[foobsr]

TFA: "Gould says it's pretty clear ants don't have maps in their heads and don't recognize markers along the route."

Quote: "Celestial cues, such as the sun or patterns of polarized sky light, appear to have no detectable effect in the precise homing orientation of foragers of Paltothyreus tarsatus. Field and laboratory experiments reveal that canopy patterns are a major influence in the home range orientation of this ponerine ant, a common species in African forests. Canopy orientation appears to be well suited to the restrictive lighting conditions of tropical forests."

c.f. Canopy Orientation: A New Kind of Orientation in Ants; BERT HÖLLDOBLER, 1980

Quote: "Cataglyphis bicolor, an ant widely distributed in North Africa and the Near East, orient to the sun as well as to visual patterns of the environment. These two mechanisms can be separated. Foraging ants (hunters) orient to terrestrial cues as long as possible, and only after these have become ineffective do they switch over to the menotactical sun orientation. In the digging individuals, however, the visual knowledge of locality is significantly inferior to that of the hunters. Diggers vary considerably in size, but hunters belong to the largest size group. In addition, the largest and smallest individuals orient differently toward black and white areas and stripe patterns."

c.f. Homing in the Ant Cataglyphis bicolor; Rudiger Wehner and Randolf Menzel, 1969

How to become an expert 'in ants' these days?

CC.

True masters of the Earth

[criptic08]

If ants have mastered abstract thinking we're all in deep trouble.

Re:True masters of the Earth

[not-my-real-name]

Read the book "City" by Clifford Simak. You might be able to find a copy at a used book store. You'll never look at ants and dogs the same...

If this means ants can count,

[MrMista_B]

then so can gears, heartbeats, waves, and anything that is capable of producing a periodic rhythm.

I can prove you wrong

[Anonymous Coward]

Cause wouldn't a built in clock in the ant produce the same result.
They would talk for a specific amount of time, then stop.

If I can come up with an other explanation so easy, how can they say ants can count?

Re:I can prove you wrong

[4D6963]

They can count time?

Re:I can prove you wrong

[LordAndrewSama]

perhaps in an egg-timer like way. release a chemical at a fixed rate. then on the way back, release the same amount of chemical at the same rate.

then travel would also be at a fixed rate. hmm, they should test by delaying ants somehow, since the rate of travel would change, they would get to the wrong destination at the right time.

Re:god, that name!

[Anonymous Coward]

full disclosure: i lolled

Surely..

[mxh83]

Surely there's better stuff to discuss than ants on a site like slashdot? When did this site become animal planet?

Phase IV

[julesh]

For anyone wondering why this story is tagged phaseiv...

I thought it was pretty cool, because AFAI knew I was the only person who remembered this film.

avoid the "pom" word on Net

[Anonymous Coward]

> He could as well go "Pom, pom, pom"

Everyone who saw "P o r n, P o r n, P o r n", please raise your hands?.... Thought so!

Re:avoid the "pom" word on Net

[Enleth]

Looks like you've got a naughty kerning algorithm...

Re:avoid the "pom" word on Net

[Dexter Herbivore]

CLINT FLICKS... anyone?

Very old news

[etnoy]

Uh, I remember reading about this over three years ago. Come on, Slashdot! Give me some news instead!

Re:Very old news

[Ash-Fox]

Uh, I remember reading about this over three years ago. Come on, Slashdot! Give me some news instead!

You must be new here...

I can count.

[antdude]

1, 2, 3, 4, 5, 6, 7, 8, 9, 10/A, 11/B, 12/C, 13/D, 14/E, 15/F, ... :D

Re:I can count.

[unick]

They probably count like:
1,2,3,4,5,10,11,12,13,14,15,20,21,...
Which is smart, because their "10" is divisible by 2 and 3.
(if we had 12 fingers doing math in our head would be a lot easier)

peh

[fireylord]

you just aim for the thorax, one shot brings them down. Would you like to know more?

Re:I heard one of the ants in the experiment speak

[Redwing]

"Home is two thousand paces north, but your mileage may vary!"

Srsly, cutting the legs?

[Anonymous Coward]

If they cut their legs, wouldn't it be more logical to assume, that the ants stopped cause of pain? Maybe the ants thought: aww shit, i'm crippled, lets die here out in the middle of the desert.

Maybe they feared that their comrades killed them anyway, if they came back with disabled legs?

Re:Srsly, cutting the legs?

[Anonymous Coward]

If they cut their legs, wouldn't it be more logical to assume, that the ants stopped cause of pain? Maybe the ants thought: aww shit, i'm crippled, lets die here out in the middle of the desert.

Maybe they feared that their comrades killed them anyway, if they came back with disabled legs?

And how would that theory explain the ones on stilts that walked past the nest? Or the fact that all of them, when placed back in the nest, had no problem finding their home the next day when they wandered out on the same legs that they would return on?

It's amazing the questions that are answered if you RTFA (and WTFV).

Old news is old

[RichiH]

Might not be relevant to the topic at hand per se, but this is _old_ news. I saw this several years ago...

Re:This doesn't prove ants can countChristmas gifs

[coolforsale127]

http://www.coolforsale.com/ Dear ladies and gentlemen Hello, In order to meet Christmas, Site launched Christmas spree, welcome new and old customers come to participate in the there are unexpected surprises, look forward to your arrival. Only this site have this treatmentOur goal is "Best quality, Best reputation , Best services". Your satisfaction is our main pursue. You can find the best products from us, meeting your different needs. Ladies and Gentlemen weicome to my coolforsale.com.Here,there are the most fashion products . Pass by but don't miss it.Select your favorite clothing! Welcome to come next time ! Thank you! http://www.coolforsale.com/productlist.asp?id=s76 (Tracksuit w),ugg boot,POLO hoody,Jacket,,Air jordan(1-24)shoes $33,Nike shox(R4,NZ,OZ,TL1,TL2,TL3) $35,Handbags(Coach lv fendi d&g) $35,Tshirts (Polo ,ed hardy,lacoste) $16,free shipping,Thanks!!! Advance wish you a merry Christmas.

Re:god, that name!

[smoker2]

That's why we spell it paedophile, and not fall into the lazy practice of spelling things the way they sound, which often results in conflicting definitions for similar words. And it's not even the same sounding word. Pedometer is pronounced ped-(rhymes with bed)-oh-meter. When you ride a bicycle, do you pedal or do you peedal ? And I think that pedes is latin, hence stampede, impede, millipede etc, whereas pod is greek, giving us arthropod, bipod, tripod, podiatrics. Paedo is greek for child, not feet, and is not confusing even if you switch ancient classical languages.

Let me guess

[NotSoHeavyD3]

Let me guess, the scientists refer to them as "A count ant". (Gets pelted with tomatoes.)

Time not number of steps?

[Anonymous Coward]

Perhaps they walk out for a certain number of minutes, turn around and then walk back for the same time. The effect would be the same as for counting steps. In particular, if their leg lengths were changed you would expect them to cover more or less distance in the same time (and with the same number of steps). Animals having some concept of the passing of time seems more likely than them being able to count to 10,000 in their heads.

More Likely Explanation

[DynaSoar]

Ants carry with them a cognitive map, that is an image of their environment (created from perceived and recalled information) and a self-image (their kinesthetic perception of their self embedded in the environment). They compare their environment with their self image constantly to locate/orient themselves and detect/evaluate potentially positive or negative environmental elements. In that comparison is direction and distance related information with which they can estimate walking time/steps. If either or both cues are changed, the result differs because their estimates based on accumulated information changes slower that real time information based on environment + self. This is a non-conscious process, just as it mostly is in us. It is essentially a dynamic component of the environment capable to actively interaction with the rest of the environment. The cognitive map is a well known mental construct from cognitive psychology, the embedded-in-environment concept is taken from evolutionary psychology. The former could count as support that fact that the suggested mechanism depends on heuristic processing producing the 'fastest good enough' result, often with some error but usually not enough to be totally wrong, as opposed to counting which implies an ongoing real time abstraction compared with a more detailed or accurate perception of the environment which is constantly updated. Besides the implication that self-awareness of some amount may be necessary for this, the cognitive load required for the heuristic process is far less than that of the more accurate real time processing. In the end, ants behave as if they are counting, as do we frequently. Just because we can doesn't mean we always or even usually do, and even if they can't 'think out loud' doesn't mean they can't have and use a process that produces as result as if they can. Lesser creatures can exhibit behaviors that appears as if higher level processing is occurring but which can be explained by the far more acceptable dynamic internal/external environmental processing concept. As an example I recommend Darwin's writings on his observations of the behavior of earth worms.

How did they give them "shorter" legs?

[gooneybird]

"Ants with longer legs would pass the nest on the way home, and ones with shorter legs came up... well... short"

I could understand how one might lengthen legs (e.g. miniature stilts), but how did the scientist shorten their legs? OMG - they cut Kenny's legs off!!!

Re:I heard one of the ants in the experiment speak

[dzfoo]

That's what she said!

Har! Har!
Oh...

      -dZ.

Counting or timing?

[TheLink]

> Passing through this little valley took so long, climbing up that hill the rhythm changed

Which brings us to the question: Are the ants really counting steps or is it based on timing?

Because you could get a similar result if it's based on timing. For example the ant walks to point X and it takes 60 seconds, so on the return journey, somewhere in the ants brain there's a countdown from 60 seconds (or more likely a increase/decrease in "potential"). With longer, but not much heavier legs the ant could still overshoot the nest because it's moving faster.

So what if you increased the slope so that the ant slowed down (or sped up) while taking the same number of steps for a particular distance. Would that change where the ant started looking for the nest? The difficulty is the ant could compensate for that - if something takes longer the "meter/timer" could be paused.

Also there's a more "analog" way of counting and there's a more "digital" way of counting.

Digital is the hard edged "1, 2, 3" count. Analog would be closer to filling a pool with buckets of water when counting up and emptying it when counting down.

Re:god, that name!

[Anonymous Coward]

you could call it "childfuckometer" as well

That wud b paedometer (ignoring the fact that neither ped nor paed mean childfuck.)

Memory

[Anonymous Coward]

Joe Ant: "One hundred seventy four thousand eight hundred and three"
Joe Ant: "One hundred seventy four thousand eight hundred and four"
Joe Ant: "One hundred seventy four thousand eight hundred and five"

Sid Ant: "Hey Joe, what's up?"
Joe Ant: "Oh, you know. Not much- just looking for grub for the Queen."
Sid Ant: "Hey man, have you seen here recently? She's lookin' hot!"
Joe Ant: "Heh, yea sure Sid. You're a worker ant. You don't have a chance."
Sid Ant: "Yea... I know. But I can dream... Anywho, I gotta head back to the hill. Smell 'ya later."
Joe Ant: "Later bud."

Joe Ant: "One hundred eighty- no- seventy eight thousand... no- eighty thousand seven hundred... no- one hundred seventy thousand... fuck."

Shamelessly inspired by this old post

Automated Alice

[BeardedChimp]

This reminds me of the book by Jeff Noon. In it Alice (of Alice in wonderland fame) travels to an alternate reality in which she has shrunk to the same size as some termites.
The termites are running around frantically while she follows. It turns out she was caught in a mathematical calculation where the termites movements could be used to solve complex problems.
Quite fun really, I recommend Vurt if you want an introduction to Jeff Noon.

Manipulating the leg length?

[Anonymous Coward]

Best euphemism I've heard in a long time.

Ummmm...cruel!

[hesaigo999ca]

>and the experiment used to test it involves manipulating the leg length of some of these ants
The would either use pieces of duck tape to hold the dismembered limbs together after having cut them to make different length legs..
or add wood chips to the bottom to increase the length beyond the leg length.

I would hate to be one of those ants on that day!

Hex!

[Anonymous Coward]

Finally the wizards at Unseen University can start their work on Hex.

depends what you mean by 'count'

[cathector]

> What I was trying to say is that counting usually involves numbers.

i would take a broad view of the word "counting" and define it as something like "the ability to remember and compare quantities", regardless of the presence or not of a theory of numbers.

with this view, the ants, the drummers, and the mamas w/ the puppies are all counting.

Re:depends what you mean by 'count'

[ls671]

http://slashdot.org/comments.pl?sid=1457756&cid=30238628

Re:I heard one of the ants in the experiment speak

[cathector]

i felt TFA had a rather stilted tone..

Not just old, wrong too

[Nigel Stepp]

Not only is this result super old, but the conclusion has also been invalidated for quite some time. Changing the structure of the ants' legs can change their ability to integrate distance in many ways. The pedometer hypothesis is but one explanation.

That explanation does not hold up when considered with other results, such as testing ants leaving and coming back over different terrains. If ants are counting steps, then hilly vs. flat terrain will cause problems (since hilly terrains require more steps than flat). Ants deal with this just fine, however. Here is one of many references showing this:

Grah, G., Wehner, R. and Ronacher, B. (2005). Path integration in a three-dimensional maze: ground distance estimation keeps desert ants Cataglyphis fortis on course. J. Exp. Biol. 208,4005 -4011.

Not timing, read the article

[imtheguru]

"Wolf and Whittlinger trained a bunch of ants to walk across a patch of desert to some food. When the ants began eating, the scientists trapped them and divided them into three groups. They left the first group alone. With the second group, they used superglue to attach pre-cut pig bristles to each of their six legs, essentially putting them on stilts. The third group had their legs cut off just below the "knees," making each of their six legs shorter.

After the meal and the makeover, the ants were released and all of them headed home to the nest while the scientists watched to see what would happen.

The regular ants walked right to the nest and went inside. The ants on stilts walked right past the nest, stopped and looked around for their home.
The ants on stumps fell short of the nest, stopped and seemed to be searching for their home.

It turns out that all the ants had walked the same number of steps"

A timing mechanism would not exhibit this property.

Re:Not timing, read the article

[techno-vampire]

A timing mechanism would not exhibit this property.

I beg to differ. If they find their way home by walking for a fixed length of time, the experiment would have come out exactly the same. That's because ants take a fixed number of steps per minute, whether their legs have been lengthened, shortened or left alone. Thus, there's no way that you can tell (from the experiment as described) if the ants are counting their steps (as the researchers claim) or walking for a fixed length of time.

Re:Not timing, read the article

[bingoUV]

ants take a fixed number of steps per minute, whether their legs have been lengthened, shortened or left alone

Do you have any links to prove this? This could be one possibility but seems unlikely. If this were true, slightly longer legged ants would get an evolutionary advantage. Legs would slowly get lengthened until legs are no more an exclusive bottleneck in their speeds. The other bottlenecks could be :

1. Energy supply to legs.
2. Traffic: Ants move in neat lines and have to deal with both co-directional traffic and oncoming traffic.
3. Cognition: Smell/step-count might take some time to get processed in their brain. If they don't take any step without knowing for sure, their tiny brain could slow them down.
4. Pain later: If I walk too fast, I have pain in my legs later, at night. It could be a similar situation for them. Maybe they have learnt to not walk so fast as to cause pain later. This will also enable them to move much faster than regular when beset with a grave danger.
5. Etc.

Re:Not timing, read the article

[techno-vampire]

Do you have any links to prove this?

No. It's pure speculation on my part, but seems (to me, at least) reasonable. Most animals have a natural pace that they use whenever possible because it's the most energy efficient, and I'd expect it to be the same for ants. I find it hard to believe without proof that ants have the understanding to change their pace depending on the length of their legs, as that would take more reasoning power than they've been shown to have.

I'm not saying that ants are aware of the passing of time, or judge their trips by it, only that from where I sit, the experiment as described doesn't rule out the possibility.

Re:Not timing, read the article

[bingoUV]

Longer legs => more distance per step. If step frequency is constant, this means power output is higher with longer legs. If energy supply to legs is the bottleneck for speed in ants, step frequency would automatically decrease. Whether the ants want it or are even aware of it. Ants having the understanding of elementary Neutonian dynamics doesn't even come into picture.

Look at the other possible bottlenecks for ant walking speeds I listed in my earlier post. Your hypothesis holds true only if leg-length is the biggest bottleneck. Which looks pretty unlikely, as I argued in my earlier post. Do you have arguments to prove:

1. Your hypothesis holds true even if leg-length is not the bottleneck
2. Leg-length as speed bottleneck is likely
?

Re:Not timing, read the article

[techno-vampire]

Do you have arguments to prove:

Of course not. It's pure speculation.

counting or timing?

[JumpSocial]

Perhaps the ants aren't counting. An individual steps at the same rate of steps per minute and they just time how long they travel.

Re:god, that name!

[LanMan04]

Except you didn't use this: http://en.wikipedia.org/wiki/%C3%86

Now who's lazy?

Lovely unfounded conclusions...

[Anonymous Coward]

Couldn't these ants have a notion of *time* instead?