  Newborn animals have advanced perceptual skills at birth, but the nature of
this initial knowledge is unknown. Is initial knowledge flexible, continuously
adapting to the statistics of experience? Or can initial knowledge be rigid and
robust to change, even in the face of opposing evidence? We address this
question through controlled-rearing experiments on newborn chicks. First, we
reared chicks in an impoverished virtual world, where objects never occluded
one another, and found that chicks still succeed on object permanence tasks.
Second, we reared chicks in a virtual world in which objects teleported from
one location to another while out of view: an unnatural event that violates the
continuity of object motion. Despite seeing thousands of these violations of
object permanence, and not a single non-violation, the chicks behaved as if
object permanence were true, exhibiting the same behavior as chicks reared with
natural object permanence events. We conclude that object permanence develops
prenatally and is robust to change from opposing evidence.
