title: Yawning...and why yawns are contagious: a theory on evolution and atavism.
authors.forename: Hari
authors.initials: H
authors.lastname: Prasad
mesh_terms: D000819:Animal Communication; D000818:Animals; D001143:Arousal / Q000502:physiology*; D005075:Biological Evolution; D001921:Brain / Q000502:physiology; D006801:Humans; D008954:Models, Biological; D008962:Models, Theoretical; D009043:Motor Activity / Q000502:physiology; D009068:Movement; D010614:Pharynx / Q000502:physiology; D015000:Yawning / Q000502:physiology*