Life Sciences Term 3

Artificial selection

• Artificial selection is the intentional reproduction of individuals in a population that have desirable traits
• Some consider domesticated animals to be the ultimate products of artificial selection
• Food crops – many of the green leafy vegetables have been selectively bred from the ‘wild mustard’ plant
• Thoroughbred racehorses are one example of artificial selection of animals
• The meats we eat are the result of the careful selective breeding of cows, pigs, sheep, and chickens
• Our pets are a far cry from their “wild” ancestors. Cats and dogs, which were originally domesticated for pest control, hunting, or shepherding, eventually were bred to become companion animals
• There can be a downside to artificial selection
• Because this process essentially removes variation in a population, selectively bred organisms can be especially susceptible to diseases or changes in the environment that would not be a problem for a natural population
• Inbreeding — the mating of closely related individuals — is also a problem
• In dogs, this has resulted in breeds that have health issues ranging from decreased life span to hip dysplasia