These weeks are a crucial time for the puppy’s brain development. This is when puppies are at their most curious and willing to approach people, but at the same time their natural fearfulness starts to be shaped by their environment. This increase of fearfulness is a gradual process over the next couple of weeks and so now is the time to introduce all manner of sights, sounds, and people – and also more interesting toys and experiences as this will ultimately determine how well balanced the puppy will turn out as an adult.
In some more reactive breeds, this fear response and hazard avoidance starts earlier and increases rapidly. For these breeds it is important that the tasks detailed below are worked on as early in this period as possible whereas the less reactive breeds have a later onset of hazard avoidance and so you can be a bit more relaxed about these tasks.
To give you a rough idea, the hazard avoidance in the wild wolf (who shares our dogs’ ancestors) starts around 19 days old. In the average dog it starts around 49 days old. For the German Shepherd Dog (one of the more reactive breeds) it starts around 35 days old and in the Labrador (one of the least reactive) it can start as late as 72 days. These are all approximate as each individual dog will be different – but it gives you an idea of how hard you are going to have to work in these two weeks!
This is also the time to start to teach the puppy to be happy on his own away from his littermates, and to bond even more to humans.