Why Do Humans Sleep at Night Instead of During the Day

question 25

Multiple Choice

Why do humans sleep at night instead of during the day?

• A) There is most danger at night, when we cannot see well.
• B) There is least danger at night, so we are safe to sleep.
• C) Our bodies, particularly our eyes, are not capable of functioning properly at night.
• D) There is no reason; it just became habitual in humans.

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Definitions:

Dependent Variable

The variable in an experiment that is measured to see if it is influenced by the independent variable.

Experimental Confederate

An individual in a study who is secretly working with the researchers, posing as a participant but following a scripted behavior.

Facial Expressions

Visible contractions or movements of the muscles beneath the skin of the face, considered as a form of nonverbal communication.

Emotion Regulation

The ability to influence one’s emotions.