Stars as a Guiding Force

In 1958 nocturnal migratory species were observed to naturally turn and yearn to fly in their respective north-south directions relative to the time of year.  While in captivity, this behavior was replicated using a synthetic night sky inside a planetarium. However, when this was removed, the subjects were disoriented and lacked proper positioning. In addition, when the planetarium was reversed, the birds too reversed the direction of their desired movement. This concept was then elaborated on in 1967 by determining which starts or constellations were used by these subjects.  It was presumed that the north star, a large and fixed beacon, would be used, however it was determined that constellations near the north star, such as the big and little dipper, were used instead.  The subjects also showed flexibility and were able to utilize several constellations for travel when other were removed.