Artificial Selection – AP Biology College Board Revision

Understanding Artificial Selection

Artificial selection is a process in which humans actively choose specific traits that they deem desirable, thereby affecting the evolution of a species.
This concept is also known as selective breeding or domestication.
Artificial selection can lead to significant changes in the physical characteristics or behaviours of a species over a relatively short period of time.
It is a powerful tool for creating new breeds or varieties within a species, for instance, in domestic dogs or cultivated plants.

The process begins with the identification of a desired trait within a population.
Individuals showing the desired traits are selected to breed, while others are not allowed to reproduce.
Offspring produced through this breeding process are then examined for the presence of the desired traits.
Those showing the traits are selected for further breeding. This selection-breeding cycle continues until the trait becomes a common feature of the population.

Artificial selection can lead to extreme modification of traits.
It has been a major contributing factor in the development of a wide range of domesticated animals and cultivated plants, fundamentally altering their ancestors’ original characteristics.
An example of this is the vast diversity seen in domestic dogs, which all stem from the same ancestor, the wild grey wolf.
It can, however, also result in negative impacts, such as reduced genetic diversity and an increased risk of genetic diseases.

In contrast to natural selection, which is driven by the pressures of the natural environment, artificial selection is guided by human choice.
Natural selection favours traits that give organisms an advantage in survival and reproduction, while artificial selection favours traits deemed desirable by humans, irrespective of their impact on survival.