Smil­ing hu­man faces are at­tract­ive to dogs – thanks to oxy­to­cin: Researchers found that oxytocin made dogs interested in smiling human faces. It also made them see angry faces as less threatening.

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Smil­ing hu­man faces are at­tract­ive to dogs – thanks to oxy­to­cin: Researchers found that oxytocin made dogs interested in smiling human faces. It also made them see angry faces as less threatening.