Dave Munger in Seed Magazine:
The nervous system of the desert ant Cataglyphis fortis, with around 100,000 neurons, is about 1 millionth the size of a human brain. Yet in the featureless deserts of Tunisia, this ant can venture over 100 meters from its nest to find food without becoming lost. Imagine randomly wandering 20 kilometers in the open desert, your tracks obliterated by the wind, then turning around and making a beeline to your starting point—and no GPS allowed! That’s the equivalent of what the desert ant accomplishes with its scant neural resources. How does it do it?