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Ants Use Pedometers to Find Home
Ant writes "New Scientist (a short video clip included) reports that desert ants have an internal pedometer that keeps track of how many steps they take, according to a new study. The insects seem to rely on this system to find their way back to the nest after foraging. Other insects may also possess this pedometer-like system. Some types of ants appear to use visual cues or leave scent trails to find their way home. But desert ants have a remarkable ability to retrace their steps from their nesting site even though they travel on flat terrain that is devoid of landmarks, and any odors quickly fade in the hot temperatures."
Wouldn't it be fun to give the ants little shoes to make their legs longer? That would screw 'em up pretty good.
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It's actually a surprisingly complex system. They not only measure how much distance they've covered, but also every turn they've made. They basically "remember" a complete log of their journey, and are able to reset it every time they return to the nest.
I thought this was a really cool paper too, and it would be really interesting to know in greater detail how exactly they count their steps.
:)
And if some alien race comes down to do the experiment on us, I hope they attach stilts to my legs rather than creating stumps out of them.
Are you BioCurious?
But it involves massive amounts of alcohol for it to work properly.
Commenly called the beer scooter, it is a mechanism that guides you safley home to your bed, no matter how far away or how drunk you get. Its side effects can be unfortunate though as unexplained cuts and bruises plus a bank account severly depleted of funds are commen occurances upon awakening.
From TFA, the video of the ant with stilts (worth a watch):
http://www.newscientist.com/data/images/ns/av/dn94 36.mpg
Thought it was pretty neat; the ant begins to look like a spider with the longer legs. The video didn't seem to have any additional bearing to the study, though. You'd need to read TFA for how the stilts helped in their conclusion.
1mm taken off of each leg from an ant *is* a significant amount.
Are you BioCurious?
One of the few zoological fields were you can chop off your subjects legs without needing to sign any legal paperwork!
I for one welcome our new giant ant overlords
They should have constructed a mini treadmill (complete with moving walls) --seriously-- to see if the ants with normal legs still walk the same distance for a reward. That would really drive there point home.
have you looked at an ant lately?
When you legs are only 5 mm long to start with, 1mm is a SIGNIFICANT change- 20% shorter.
Take a hacksaw and cut your legs a few inches below the middle of your shin, see how well you do.
No unauthorized use. Trespassers will be shot. Survivors will be shot again.
It would be wonder if the ants could walk at all without a piece of their legs.
http://buddytrace.com/
Well, what would you say when you are 5ft tall and someone just cut off 1ft of your legs. I think the pain and agony of the cut-off legs is what made them have trouble finding home. I think humans with 1/2 their legs being cut off would also have trouble finding home. I think it would be better to make the legs LONGER without causing them pain (nanotubes...) would validate the experiment
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I have to wonder with an experiment like this how the scientists went about modifying the ants. I would think that the ants would be disoriented a little by these changes, and the results might be affected in a way that would not have to do with the 'internal pedometer.' This might have been considered, but it might not have been.
"Why would ants travel 50% further or less because of a 1mm (+/-) change in their leg length?
Proportionally, 1mm is a very small change."
Dont know how long the ants legs are where you come from, but around here 1mm is a major proportion of ant leg!
I RTFA. (first mistake -- I know)
What if the ants basically know how tired they are after they get home?
I know when I walk a long way, I get tired at about the same distance. I'm not counting my steps and I don't think my brain is doing it subconsciously.
They need to weigh an ant down or attach it to a tiny helium balloon for the trip to rule it out. It's no sillier than putting stilts on them.
I sure wish there were more information. If this is true; it's somewhat interesting. But with so little to go on, it could just as easily not be true.
As the most obvious example to spring to mind; they tried ants with legs (we're left to assume) 50% longer that went 50% further than home and legs 50% shorter that only got halfway home. They then say this is because he counts steps -- obviously each step takes the one ant 50% further and the other 50% shorter.
So what if the ant goes by the amount of time it's been traveling; nothing to do with counting steps at all --?
You'd expect exactly the same results.
I hope it's just the awful article -- if the study is so poor they've really learned nothing.
... I learned from SimAnt
"The more corrupt the state, the more it legislates." - Tacitus
The original research paper appears in this week's edition of Science and can be found via this page: http://www.sciencemag.org/cgi/content/short/312/57 82/1844a
(subscription needed to read the full paper).
Yay science!
-ubuntu others as you would have others ubuntu you.
The summary mentions that, man. Pheremones = scent trails.
I used to carry a bottle of whiskey for snake bite. And two snakes. -Nefarious Wheel
Have you looked at a desert ant lately?
Their legs are longer than 5mm, as the higher they are off the sand, the cooler it is.
Rear leg length is normally much longer than the others, as an ant will stand up on it's rear legs to elevate when it needs to cool off.
I'll concede the larger point, that 1mm is a significant portion of the leg length, but it definitely isn't 20%
[Fuck Beta]
o0t!
In a book I read when I was younger, if you wipe your finger along a big line of ants they lose the scent and get lost. I've done that alot and they do get losr abd run around like chickens with their heads cut off.
Fallout 3 will suck.
What if I find one of these ants on its way home and I pick it up and move it back a few meters (or feet), would it therefore be forever destined to wander the Earth? Or will it just create a new home a few meters (or feet) from the original?
it is only after a long journey that you know the strength of the horse.
Many beach/land crabs use the same system. They also have built-in abilities to make calculations on the quickest diagonal path to their burrow - ie the pythagorean theorem. One guy did some experiments where he would do things to mess up the step count of the crabs to their burrows, and they always were displaced by the exactly difference in step count. The crabs have no idea where their burrow is or what it looks like, they just know how to walk there. It must be the same in ants.
You can lead a horse to water, but you can't make it dissolve.
but I just use ~
"Our opponent is an alien starship packed with atomic bombs. We have a protractor."
Does this mean that Ants are smarter than early versions of Windows ?
Wanna fight ? Bend over, stick your head up your ass, and fight for air.
I propose testing the pedometer theory on the following animal:
Homo Sapiens
Berserk Manga > All
...Cool? Way to go ants!
It's poetry with a beat behind it! And guns! They're like beatniks with automatic weapons.
So it can't be tiredness, that would only work for two seperate journeys, not a round trip.
What could work is "fuel" consumption. This is probably the same both ways but again fails because the ant is on a feeding trip. He will be travelling empty on the way to the food source and carrying food on the return trip wich probably cause him to burn more fuel.
Just get out the old car anology. Your "tired" idea translates then to the heat of the engine. a trip on even terrain should see the engine heat up to the same degree but on a round trip to the shops the engine would not cool down to the same level as when you started.
The fuel consumption would also not work because on the return trip your car will be heavier.
So how do we measure distance in a car? Oh wait with a pedometer like device wich same as with the ants will be screwed up if you change the size of your tires.
Funny experiment, chopping legs of ants and giving them stilts. I bet that impresses the girls.
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
I'm wondering which drug you have to take to come up with the idea to tie stilts onto ants? This just sounds like something a drunk guy would come up with, except that that normally ends with someone loosing some fingers and teeth, not a scientific article. Of course, both results have the same attractive results with women.
In outback Australia, ants cut legs off you!
It's been a while since I worked on this, but these idea have been propagated through networking protocols for years. When I was in University at Dalhousie I spent quite a bit of time on a directed study of somethink called the 'AntNet Routing Protocol'.
:-)
The idea was based on the pheramone trails left behind whne ants seek food. You see, one ant leaves behind a trail, not a big one, but a small scent to be picked-up by other ants. When it finds food, it will retrace it's steps backwards and double the intesity of the pheramone trail. If another ant happens upon a trail, it will follow the trail to the food and increase the trail's intensity again. If the trail ever ends without a prize, ants look around to try and pick-up the trail again. Simple concept, right?
Adapting this behaviour from ants to packets on a network was easy. You had ants that walk forward and ants that walk backwards. Forward ants would collect hostnames, IP address and time stamps as they passed through any PC and kept going to their host. Backward ants updated the routing table when they retraced their steps. If any route had a lower cost (latency) then the entry already in the routing table, then an updated entry was posted. There was also a hidden advantage to all this - if, for any reason, a node went down or dropped off the network it was easily and quickly detected. Furthermore if a link went down, alternate routes were already in place if you kept double-layered routing table... quick, easy and fast network response times were the result. Consider time stamps like a tick on a pedometer...
In case you're wondering, all computers on the network ran NTP to sync the time and give us one less hassle to worry about (this could be easily incorporated if need-be).
My main area of research was to figure-out where and when the Ants started to impeed the network instead of help it. I found it to be a function of the number of discovery ants versus time and nodes on the network... some pretty rough math ensued from what I remember, but the time delta between discovery ants was paramount in any effective benefit to the network.
Food for thought... or to the trail with the most ants.
It must have been something you assimilated. . . .
Dunno - I'd guess though that the ant lost count of its steps, or counted properly and didn't end up in the right place because it wasn't the same number of steps anymore. At that point, the ant probably starting looking for the nest the old-fashioned way, rather than just giving up on the spot. As for pain, anyone who has ever gotten in a fight with an ant can tell you that pain doesn't bother them overmuch as far as fighting goes, they keep biting or running away just as hard until they literally can't.
I can see that little fellow going "WHEEEEEE!!" all the way there, seems to be much better off than the ones with shortened legs - though guessing by the premise without reading the article, I'd bet that that ant had just as hard a time finding home sweet home as the leg-shortened ants.
Jonathan Connell* built a mobile robot @ MIT which used a not too dissimilar system for navigation. It counted the number of doors that it passed through, and the number of turns to the left. This robot, Herbert, had the goal of collecting soda cans and would wander about the lab autonomously collecting these cans and returning home but making an appropriate number of entries through doorways and turns to the right using a magnetic compass as a rough guide. There was no internal map, no master plan, to 3D model of the world, no GPS yet this robot was able to navigate very complex, real-world spaces effectively. It's interesting to see that there's a biological model here that validates many of these assumptions.
** I hope I'm correct on the details... I'm going from memory from a reading of Connell's Master's Degree disseration I read probably ten years back... I believe the title was "Minimilist Mobile Robotics" but I'm certain it was published through Academic Press. This was one of the early MIT Mobile Robot Lab robots to use Subsumption Architecture.
Perhaps the ants got distracted because some fucker
strapped stupid poles to their legs making it
damned impossible to walk?
I wonder how differences in the number of steps changes the ant's final destination. As a kid, I was one of those avid watchers of ant-lions who either saw an ant get trapped or take many steps (usually in that cylindrical cone of a pit) to possibly emerge and continue on its merry way.
In the case where scent was not an option and the ant was disoriented; not only by both the change of direction in the ant-lion cone, but the many (and very many) steps it would take to escape the trap, I would imagine that it would probably not make it back to the rest of its brethren.
So were they able to analyze the ant's brain and figure out where the count is stored? Is it binary? I'm curious what a neural based counting system would look like, since it's relatively simple in computers.
> Proportionally, 1mm is a very small change.
Proportionally, Ants are very small.
The other day, when I got in the shower, I saw an ant trying to carry his dead comrade... err... somewhere. He was getting there via walking in circles. In fact, his path was so precise, that when I got out of the shower 40 minutes later, he was still carrying his buddy around in circles. Then my dog stepped on him. That's one hell of a tracking system!
Multiply that 1mm difference by the number of steps they need to take to cross said large desert.
"Thanks for all the money you paid to us. We've used it to buy off ISO among other things" -Microsoft
In a similar test of bar flys, scientists cut off the legs at the knee (50%) of all guests at a local bar, and discovered that the guests on average only made it half way home.
The scientists in this case now speculate that the guests must be using a pedometer to find their way home.
"Fix it"
On the serious side,
1. The ants are decades ahead of us in pedometer miniaturization.
2. They've managed to keep their advanced technology secret for years.
3. They finally revealed it only after brutal mutilation.
These three facts together should give us pause.
Play Command HQ online
When the researchers shortened the ants' legs the insects had trouble finding home.
Hmm, I wonder, would the researchers would have any trouble getting home if their legs were shortened instead?"When the researchers shortened the ants' legs the insects had trouble finding home." No, they were maimed and crippled. Thats why they couldnt find their way home! (I was going to say something about step counters not working in a wheelchair but I i thought it might be bad taste)... Damn
We dont need no pedometers. We dont need no leg control. Hey, researcher! leave those ants alone!
Sweet video of an ant running. Very helpful in describing the effect. [/sarcasm]
I have an ant problem in my house this week. I'm finding themin 3 different rooms meandering around. I was going to buy some ant killer after work today -- something in order of the stuff where they walk in it, take it back their hive, and infect the whole place. It appears now all I have to do is shout "4! 12! 37!" and they'll lose count and never get back home anyhow....
"All great things are simple & expressed in a single word: freedom, justice, honor, duty, mercy, hope." --Churchill
Ok but doesn't explain how they get back because you could take that same ammount of steps and go in a different direction, so they must have something else.
I'm sure there's an internal GPS in there too,,,just haven't found it yet because they are so tiny
What I find most interesting is how important it is to an ant colony to have inhabitants which wander and can navigate back to the nest. It seems so important, they've devised two different methods; one which depends on odor and this pedometer method. This specific need is so fundamental to their existence, it appears to drive their evolution.
I don't have a subscription to read the original article, but the glossy schtick pointed to in the original post was pretty weak: "we mutilated ants and they couldn't find their way home, and if I buy fish it won't rain on monday, so therefore they have a pedometer hidden inside their gasters!". Hopefully the original has more actual science.
Silver ants (they look more like they are chrome-plated than silver) also live in the Sahara. They come out at the hottest time of day, when all predators are hiding, and they are extremely reflective. They have a special gait that allows them to keep half their feet off the sand in the shadow of their bodies, and they keep switching off so their feet don't cook. They move about in a fairly normal search pattern, but when they find something they run directly back to the nest without retracing their original route! Although they are believed to have good vision, their environment contains almost no visual cues - one sand dune's pretty much like another - and they will pass through territory they haven't seen on the way back to the nest.
Silver ants are also very hive-oriented or "altruistic". Individual foragers will go past their survival distance looking for food, but they turn around and come back so that their dead bodies are within the survival distance and can be recovered by other foragers. That way, if there is a food/water source that is further out than an ant could travel without such resources, they will still find it and use it.
All this is from memory and the wiki article is lame. If anybody has some good links for silver ants please post!
Humans have an internal system to gauge how far they've walked continuously too. It's called fatigue.
Oh, say does that Star-Spangled Banner entwine / The myrtle of Venus with Bacchus's vine?
But can they do calculus!
Having to work for a living is the root of all evil.
Evolution is an existing, observable process. That things evolved is a contentious proposition.
Sort of like the presumptuous notion that mountains and valleys were formed by geological processes and not some other phenomena that, unknown to humanity, happen to produce mountains and valleys as well.
Now I do "believe" in evolution and natural selection, and there are better examples than this.
But this (alone) doesn't either prove or disprove evolution at all, much less "conclusive proof". Just because species X has A, and species Y has B, it doesn't mean they couldn't have been created like that.
E.g., look at the bears in World Of Warcraft. Some are white, some are brown, some are black, some are bigger, some are smaller... but there was no evolution involved anyway. Some game designer or artist just went and modelled a white bear. So _if_ I was to believe in the Big Game Designer In The Sky, I see no problem why He can't create two species of ants which work differently. I mean, seriously, why is that impossible to create?
E.g., look at some of the artifficial things humans have been creating by genetic engineering. E.g., rabbits which glow in the dark. You could say the same. "Wow, so a rabbit didn't see at night, so it evolved into a light source. It's conclusive proof of evolution." Well, nope, not really. A human just created that rabbit.
The "proof" of evolution is in the intermediate steps, not in the fact that two species are different. Just being different won't even start to contradict creationism. Sure, they'll say, they were created different. What "proves" evolution (or at least makes a very compelling point for it) is finding enough intermediate steps to actually show that species A really transformed gradually into species B. E.g., finding enough bones and such to make a compelling case of how and over what timeline did a small-ish ape turn into Homo Sapiens.
A polar bear is a cartesian bear after a coordinate transform.
Mod parent up +1 tasteless...no wait, I didn't mean it like that.
To have a right to do a thing is not at all the same as to be right in doing it
There must be a way to make an ant calculator. Sort of like an ant farm maybe. Lets make one!
this is the most important sig ever! In your face 446154!
Yo may also take a look to my own simulator of Ant's food-gathering behaviour:
r m
http://www.geocities.com/chamonate/hormigas/antfa
It tries to emulate the usual ants, that find the food and the way back using pheromone traces.
It's not a brain, but a small nerve bundle. They are close to robots really. Some bio sensors, and a small preprogramed amount of logic.
Otherwise, they would have taken over the world by now.
OOh wait, they HAVE.
How much is your data worth? Back it up now.
> Wouldn't it be fun to make their legs longer?
They did!
perform surgery on ants as a kid, and who wanted a grant to do the same, but get paid for it.
That said, are we sure that the ants aren't just counting in their heads? Maybe the reason they get disoriented goes something like this:
951, 952, 952, hey what's happening?
OOOOOOWWWWWW!! Damn, they cut off my legs!
OUCH OUCH OUCH! Now I'm in some sticky goop!
Finallly, that's - ouch - over - ouch.
Ok, where - ouch - was I - 591 steps from home.
-- Tigger warning: This post may contain tiggers! --
"Three-hundred seventy-thousand, five-hundred and three ..." ..." ..."
... waitaminute.. DAMMIT!"
"Three-hundred seventy-thousand, five-hundred and four
"Three-hundred seventy-thousand, five-hundred and five
"Oh hey Joe, how's foraging?"
"Can't complain. Did you catch the game last night? Eight to one baby, totally blew the spread!"
"Eight to one, yeah that was pretty insane. Well, gotta get back to the grind."
"See ya in the tunnels."
"Three-hundred seventy thousand, eight-hundred and one
Done with slashdot, done with nerds, getting a life.
On the upside, the ants had no trouble finding personal injury attorneys to take their case.
Ants making your life miserable? Call Orkin 2120.
We have developed, through selective breeding, telepathic mice that emit random numerical counters at a frequency that disrupts an ant's internal pedometer. Silently these mice work to confuse ant workers so they can't return to their nests.
Remember: when ants can't dead-reckon, they're just dead!
So, call today to have Orkin 2120 get rid of your ant problem today!!
I don't buy for a second the idea that the ants count their footsteps. Of all the explanations they could come up with, that has to be the most ridiculous.
Years ago, nobody was sure how honeybees knew how far they were flying, whether it was visual or they kept track of how much energy they burned, etc.. Nobody suggested they counted wing flaps, because that's just stupid.
Anyway, it was proven that bees use visual cues. Not landmarks, like this article seems to suggest is the only way, but by how fast it appeared the terrain flew past them. This was proven by having bees fly down wide striped tubes and narrow striped tubes. The bees thought they were traveling faster (and thus farther) down the narrow tubes.
Someone should do the same test with these amazing counting ants.
What the hell do you think those antennas are for?