Ants of the Sahara desert, Cataglyphis by name,
are skillful navigators. While foraging and homing over
distances of several thousand times their body lengths,
they accomplish truly formidable tasks. They use a pattern
in the sky that is invisible to man to steer their compass
courses, and then they integrate all angles steered and
all distances covered by remarkable acumen. This system
of path integration works even in completely featureless
terrain. In addition, Cataglyphis can use landmarks
by employing photographic skyline memories. Finally, they
rely on search strategies that are much more efficient
than a random walk would let one assume.
This talk focused on the behavioral performances as well
as on the sensory and neural mechanisms that are involved
in mediating this behavior. How can a 0.1 -mg brain equipped
with a panoramic compound-eye system accomplish these
awe-inspiring modes of behavior? The presentation focused
on the general sensory stratagems employed by Cataglyphis,
and showed that this small-brain navigator uses simpler
tricks than meets the human designer's eye. Cataglyphoid
robots are used to test the hypotheses derived from neurophysiological
analyses.
The general message is that a high-level task can be
solved by the cooperation of a number of low-level systems.
These low-level systems are adapted to the particular
ecological niche, within which the desert navigator operates.
