Figure 40.9: An Insect Odometer Desert ants navigate by path integration, which requires information about both direction and distance. How do they measure distance? Matthias Wittlinger and his colleagues investigated the possibility that Saharan desert ants (Cataglyphis fortis) “count” steps to keep track of how far they’ve walked.a Because every stride is a certain length, the number of steps can theoretically measure the distance traveled.