Answer: During the second year, toddlers become consciously aware of the self’s physical features. Around age 2, self-recognition—identification of the self as a physically unique being—is well under way. Children point to themselves in photos and refer to themselves by name or with a personal pronoun (“I” or “me”). Soon children identify themselves in images with less detail and fidelity than mirrors. Around age 2½, most reach for a sticker surreptitiously placed on top of their heads when shown themselves in a live video, and around age 3 most recognize their own shadow. Nevertheless, toddlers make scale errors, attempting to do things that their body size makes impossible. For example, they will try to put on dolls’ clothes, sit in a doll-sized chair, or walk through a doorway too narrow for them to pass through. Possibly, toddlers lack an accurate understanding of their own body dimensions. Alternatively, they may simply be exploring the consequences of squeezing into restricted spaces, as they are far less likely to try when the risk of harming themselves is high—for example, if the too-narrow doorway is next to a ledge where they could fall. Scale errors decline between ages 2 and 3½.