softselfsignificance npr.orgTickled Pink: Scientists Have Determined What A Happy Rat Looks LikeBy tickling rats and then photographing them, researchers found that a rat's ears are more pinkish and are positioned at a more relaxed angle when it is experiencing positive emotions. aboutpetrats Tickled PinkA big shout out and thank you to @topdogofdreams for sharing this fascinating, wonderful article. Source: aboutpetrats