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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."
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.
There's a video on the site that show the ants on stilts. Ants on stilts man! It doesn't get an better. And I thought my job was weird.
http://religiousfreaks.com/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.
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).
I have an access to the article and according to the authors:
The normal ants walk at average speed of 0.31 m/s
Stumped ants walk at average speed of 0.14 m/s
Stilted ants would be expected to walk faster. But their average speed was measured to be 0.29 m/s. They think its probably due to the increased weight of the glue and stilts.
So, your argument regarding the time taken to travel back is probably not true.
Furthermore, in their statistical modeling they adjusted for the speed of the ant among many other factors.
Umm, how exactly would that cause any problems... unless of course you mean to remove the shoes once they get to the destination?
"couldn't they just have moved "home destination" by shifting it around a bit instead of cuttiny legs off the pests ?" Moving home to somewhere closer or further away does nothing to determine their method of navigation. Even if you put them on a treadmill, they could be using an internal clock or "how tired they get" (?) to determine when they've gone far enough. The only way to narrow it down to a pedometer is to make each of their strides take them a different distance than they are used to.