Selective breeding

Selective breeding or artificial selection is when humans breed plants and animals for particular genetic characteristics. Humans have bred food crops from wild plants and domesticated animals for thousands of years.

Steps of selective breeding

Selective breeding takes place over many generations. The main steps for both plants and animals involve:

1. Deciding which characteristics are important enough to select.
2. Choosing parents that show these characteristics from a mixed population.
3. Breeding these parents together.
4. Choosing the best offspring with the desired characteristics to produce the next generation.
5. Repeating the process continuously over many generations, until all offspring show the desired characteristics.

An example of this can be seen in cows, as they can be bred to produce milk and meat.

Farmers selectively breed different types of cows with highly desirable characteristics in order to produce the best meat and dairy. This means the farmers can make the most profit.

Characteristics can be chosen for usefulness or appearance.

Desired characteristics in plants:

• disease resistance in food crops
• wheat plants that produce lots of grain
• large or unusual flowers

Desired characteristics in animals:

• animals that produce lots of milk or meat
• chickens that lay large eggs
• domestic dogs that have a gentle nature

The new varieties may be economically important. For example, they may provide more or better quality food, or allow farmers to feed more people.