How did scientists test the hypothesis that birds navigated using the sun moon and stars?

Scientists tested the hypothesis that birds navigate using celestial cues by conducting experiments that involved manipulating the availability of these natural navigational aids. In one approach, researchers used planetarium settings to simulate the position of the sun, moon, and stars, observing how birds responded to these altered cues. Additionally, field studies involved tracking migratory patterns of birds during different times of day and under different weather conditions, assessing their ability to orient themselves without solar or lunar guidance. These experiments collectively provided evidence supporting the role of celestial navigation in avian migration.