Dogs have been bred for many different characteristics: physical attributes coat color, height, weight, muscle mass, etc. intelligence ( Dog intelligence ratings ) instinctual behaviors herding, tracking, retrieving, guarding, etc. Purebred dogs are true breeding lines, just like the pea varieties Mendel used to study inheritance.
(Dogs; have been bred; T:for many different characteristics) (instinctual behaviors; herding; ) (Mendel; to study; inheritance)
Dogs instinctual behaviors Mendel
have been bred herding to study
T:for many different characteristics
inheritance