Babies fixate on faces from birth. This article from Parenting magazine explains:
When researchers showed newborns a picture of three dots arranged as a face (two dots for eyes and one dot for a mouth), the babies looked at it longer than they did when the dots were arranged in other ways. "Babies are hardwired to recognize faces, which helps them connect with their caregiver early on," says Michael Frank, a brain and cognitive sciences researcher at the Massachusetts Institute of Technology. "They like to look at anything that resembles a face, even something as abstract as an electrical outlet."
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