A bird is trained to feed from the south end of a circular cage. The bird is then placed in a light-controlled room and is phase-advanced by 6 hours. If the bird is returned to the circular cage at noon, where will it search for food?
A) North
B) East
C) South
D) West
E) Northwest

Question

Quizplus · Accepted Answer

When the bird is phase-advanced by 6 hours, its internal clock advances by 6 hours as well. This means that its feeding behavior will also shift by 6 hours.

If the bird is returned to the cage at noon, it will still try to feed in the direction that corresponds to its internal time of 6:00 pm (which is 180 degrees away from noon). Therefore, the bird will search for food in the direction that is 90 degrees clockwise from south, which is east.

A Bird Is Trained to Feed from the South End