The document discusses aging white-tailed deer based on physical characteristics. It provides pictures and descriptions of deer at different ages from fawns to mature bucks over 4.5 years old. Key physical signs used to determine a deer's age include the development of its antlers, neck thickness, muscle definition, skin looseness and other proportions of the body. However, the document notes that aging deer by physical appearance is not an exact science as conditions can affect a deer's development.