Dogs can identify the stress of their owners by chemical signals.
Anyone who owns a dog knows how intimate the bond between animals and humans can be: even without a common language, the four-legged creatures can understand and feel the emotions of their owners. In layman’s terms, this is easy for humans to know, but researchers have dug deeper: how do dogs do it?
A study published in the journal PLOS ONE reported an interesting experiment that could answer the question: dogs have a special chemical sense for human emotions.
Dogs can sense stress
The study involved 4 dogs and 36 human donors who were put in a stressful situation during a difficult verbal or mathematical test and had sweat and breath samples taken. Control samples were taken from people who had not been subjected to stressful tasks.
The four dogs, Fingal, Treo, Winnie and Soot, were led into a room and instructed to smell three different odor samples. The dogs recognized and gestured to indicate which sample was from a stressed or control person. They were able to chemically detect the state of a person’s breath or sweat. Together, the four dogs achieved 93.8 percent accuracy.
The researchers explain the phenomenon by saying that the dogs probably sniffed out volatile organic compounds that the human body releases under different conditions, such as stressful situations when the body’s pulse is elevated or breathing is rapid.
Dogs have long been renowned for their heightened sense of smell and their ability to sniff out drug use or even cancer.
Previous studies have also investigated whether dogs can detect fear or happiness. Although the current study involved a small number of dogs, the results show that they can indeed smell what their owners are feeling. Whatever they do, their ability is impressive.