A recent study from researchers at the University of Glasgow has shown that humans only have four basic emotions that can be signified by facial expressions, rather than the six that previous scientific studies had identified. They narrowed the list down to include happy, sad, afraid or surprised, and finally angry or disgusted.

A recent study from researchers at the University of Glasgow has shown that humans only have four basic emotions that can be signified by facial expressions, rather than the six that previous scientific studies had identified.

They narrowed the list down to include happy, sad, afraid or surprised, and finally angry or disgusted.

For the study, subjects were asked to look at facial expressions that were computer generated and identify the emotions being displayed from the accepted range of six.

The results of the study show that the initial facial expressions for fear and surprise were so similar that the distinction must be based on a socially conditioned response rather than biological evolution.

The same conclusion was reached for anger and disgust: the facial expression is the same, and other complex signals that differentiate between the two are social functions rather than inherited.

Evolutionary explanations behind one of the facial expressions says that widening our eyes in response to fear or surprise happens so that we can take in more visual information to assess the possibly approaching danger.