There are a number of alternative theories to essentialism. An anthropologist, for example, believes that human behavior is greatly affected by the culture and environment in which he is raised.
Touch. Touch is one of the best-developed senses at birth -- and it's absolutely crucial to bonding. Cuddling your baby will make him feel warm and secure, as will swaddling because it re-creates the confined feeling of the womb. And, yes, babies explore through touch, and their preferred tool is their mouth.
Infant perception, process by which a human infant (age 0 to 12 months) gains awareness of and responds to external stimuli. At birth, infants possess functional sensory systems; vision is somewhat organized, and audition (hearing), olfaction (smell), and touch are fairly mature. However, infants lack perceptual knowledge, which must be gained through experience with the world around them.