Selective Breeding in Animals (Edexcel IGCSE Biology: Double Science)

• Selective breeding or artificial selection means to select individuals with desirable characteristics and breed them together
• The process doesn’t stop there though because it’s likely that not all of the offspring will show the characteristics you want so offspring that do show the desired characteristics are selected and bred together
• This process has to be repeated for many successive generations before you can definitely say you have a ‘new breed’ that will reliably show those selected characteristics in all offspring

Natural Selection vs Artificial Selection Table

Selective breeding of animals

• Individuals with the characteristics you want are bred together (often several different parents all with the desired characteristics are chosen so siblings do not have to be bred together in the next generation)
• Offspring that show the desired characteristics are selected and bred together
• This process is repeated for many successive generations
• Animals are commonly selectively bred for various characteristics, including:
  • Cows, goats and sheep that produce lots of milk or meat
  • Chickens that lay large eggs
  • Domestic dogs that have a gentle nature
  • Sheep with good quality wool
  • Horses with fine features and a very fast pace

• An example of an animal that has been selectively bred by humans in many ways to produce breeds with many different characteristics is the domestic dog, all breeds of which are descended from wolves:

Selective breeding has produced many different breeds of domestic dog