The genetic difference between any two members of our species is very very small.
This reflects our rather recent common ancestry (within the last 100,000 years) and most likely a severe genetic bottleneck - where only individuals with a few variations contributed to the entirety of all subsequent generations.
Two ravens from across town most likely have far more genetic difference between them than any two human beings from across the entire planet.
As is the genetic difference between a St Bernard, a border collie, a pit bull, and a chihuahua. Yet those small differences do create some significant differences in appearance and behavior between the various breeds of dog.