German researchers have discovered that desert ants appear to have an internal pedometer that guides them back to their nests.
Desert ants live in an environment where there are few landmarks and the scent trails that work for other species of ants are not available because the baking heat of the sun destroys them.
Harold Wolf and other scientists at the University of Ulm artificially lengthened the legs of ants by attaching stilts or shortened them by removing a millimeter after training them to walk 10 meters from their nest to a feeder, Science reported. They found that the long-legged ants traveled 10.55 meters while the shorter-legged ones traveled 10.25 meters.
This suggests that ants have an internal mechanism that counts steps and helps them to navigate.
"These results support the hypothesis that desert ants use a pedometer for distance measurement, or a step integrator (loosely speaking, a step counter, although the ants most probably do not literally count)," the researchers said in their report in Science.
The team also found that the ants appear able to adjust to their new stride lengths because they traveled the correct distance on later trips.
Copyright 2006 by United Press International
Explore further: Biologists report findings on ants' internal navigation systems