Everyone is familiar with the incredible sense of smell of dogs. Hence, they are able to identify the drugs, bombs, and other such items. However, it is now scientifically proven that a dog can actually recognize the personality traits of a person which helps it get a difference between the good and the bad. Specifically, in the case of a person being mean to any other person, dogs can sense it beforehand. This theory was published in the journal “Neuroscience and Biobehavioral Reviews.”
The scientists held different events to look for the reactions of the dogs to such events.
The digs went through different scenarios. First of all, a volunteer was helping another person in opening a jar while in another scene he wasn't helping the person at all in the presence of the dog. After both events, volunteers gave the dog a treat.
Results were that the dog happily took the treat from the person who helped. Meanwhile, it totally ignored the volunteer who refused to help.
Source: The Animal Rescue Site
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