Which of the following illustrates a circadian rhythm?
A) Canada geese migrate north in the spring and south in the fall.
B) Hummingbirds lay eggs when local flowers are abundant.
C) A dog barks whenever someone knocks on the door of its home.
D) Raccoons routinely sleep during the day and are active at night.

Question

Quizplus · Accepted Answer

Circadian rhythms are physical, mental, and behavioral changes that follow a 24-hour cycle, responding primarily to light and darkness in an organism's environment. Raccoons sleeping during the day and being active at night is an example of a behavior that follows a circadian rhythm, as it is a daily cycle of activity and rest.

Which of the Following Illustrates a Circadian Rhythm