Size isn't everything, but for many, it has historically been a means of telling which puppy is prone to assuming a superior position within a group. While the largest puppy in the litter can often have dominant tendencies, sometimes the "runt" can be just as assertive.
Puppy personalities come out by the age of eight weeks, when puppies play fight, compete for placement next to Mom's warm skin and compete for food. The largest male puppy has the natural advantage and may win these fights, assuming the dominant role. This leaves the other pups to work out dominance and submissive rankings. If the litter remains together for 16 weeks, these dominance roles will imprint in the puppies' minds.
While the largest male pup may have dominant tendencies, you can't completely rely on size to gauge a dog's temperament. Sometimes the smallest pup in the litter is prone to assert themselves in a dominant manner. Afterall, the tiny puppy may be picked on by litter mates and need to fight harder for food and warmth. As small puppies learn to defend themselves against litter mates, they might take on the dominant role.
Signs of Dominant Tendencies
Whether you want a dog with a tendency to be dominant or submissive (note that dominance is fluid, and there is no such thing as a 100% dominant or submissive dog, nor is there a clear "alpha" within a pack) knowing the signs of dominance can help you make the right choice for your household. If the puppy jumps on you, appears reluctant to assume sit or down positions (assuming she's familiar with these commands) are signs of dominance.
Tips for Selecting a Puppy
Size should not be a major consideration in selecting; with proper care, puppies in a litter usually catch up size-wise within two years. Physical characteristics play a role in choice. You may decide to pick a pup based on her eye color or markings. Watch the puppies play to tell which are quiet and shy, which are curious and which want your attention. Ask the breeder or shelter employee about puppy personalities. Choose the right pup for you based on characteristics, chemistry and appearance, because size doesn't always reflect personality.
About the Author
A successful website writer since 1998, Elton Dunn has demonstrated experience with technology, information retrieval, usability and user experience, social media, cloud computing, and small business needs. Dunn holds a degree from UCSF and formerly worked as professional chef. Dunn has ghostwritten thousands of blog posts, newsletter articles, website copy, press releases and product descriptions. He specializes in developing informational articles on topics including food, nutrition, fitness, health and pets.