A new study by researchers from Queens University, Belfast, and Newcastle University in the U.K. has investigated whether dogs can in fact smell when a person experiences stress. Given the excellent sense of smell that dogs have, and the fact that they have lived in association with humans for thousands of years, the researchers wondered whether dogs are able to perceive the chemical signals associated with stress in their owners.

— Read more in Stress has an odor, and dogs can smell it on us at Earth.com.