Puppy Development: From The Humane Society Web Site
Birth To Two Weeks – Neonatal Period
Puppy is most influenced by his mother.
Senses of touch and taste are present at birth.
Two To Four Weeks – Transitional Period
Puppy is most influenced by his mother and littermates.
“Eyes open, teeth begin to come in, and senses of hearing and smell develop.”
“Puppy begins to stand, walk a little, wag tail, and bark.”
“By the fourth or fifth week, eyesight is well-developed.”
Three To Twelve Weeks – Socialization Period
“During this period, puppy needs opportunities to meet other dogs and people.”
“By 3 to 5 weeks, puppy becomes aare of his surroundings, companions (both canine and human), and relationships, including play.”
“By 4 to 6 weeks, puppy is most influenced by littermates and is learning about being a dog.”
“From 4 to 12 weeks, puppy remains influenced by littermates and is also influenced by people. Puppy learns to play, develops social skills, learns the inhibited bite, explores social structure, ranking, and improves physical coordination.”
“By 5 to 7 weeks, puppy develops curiosity and explores new experiences. Puppy needs positive “”people”" experiences during this time.”
“By 7 to 9 weeks, puppy is refining his physical skills and coordination, and can begin to be housetrained. Puppy has full use of his senses.”
“By 9 to 12 weeks, puppy is refining reactions, developing social skills with littermates (appropriate interactions), and exploring the environment and objects. Puppy begins to focus on people; this is a good time to begin training.”
Three To Six Months – Ranking Period
“Puppy is most influenced by “playmates,” which may now include those of other species (people, other pets).”
“Puppy begis to see and use ranking (dominance and submission) within the household (the puppy’s “”pack”"), including humans.”