According to data recorders strapped to pigeons' heads, pigeon migration may not be too different from human navigation: the birds use landmarks to navigate, they pay more attention when in cities, and they even recognize other pigeon colonies.

In their study, the University of Zurich team hooked pigeons up with in-flight electroencephalographs (EEG) and GPS trackers. The result was data on how pigeons think while they are trying to navigate their migratory path.

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Not only does the study confirm that pigeons keep an eye on landmarks while migrating, it also shows that pigeons perk up and pay more attention when they are in changing terrain, like flying through cities or over highways. Brain activity lulls a bit when they are flying over featureless ocean, for example.