Artificial selection

Definition

Artificial selection is the process by which humans intentionally breed plants and animals for specific traits, resulting in changes in the genetic makeup of those species over generations. This practice has played a crucial role in agriculture and animal husbandry, demonstrating how human intervention can significantly influence the evolution of species. By selecting individuals with desirable characteristics, artificial selection provides insights into natural selection and evolution, illustrating the power of selective pressures in shaping genetic diversity.

5 Must Know Facts For Your Next Test

1. Artificial selection can lead to rapid changes in a species, often seen in domesticated animals like dogs, where various breeds exhibit distinct physical and behavioral traits.
2. This process can create negative effects such as reduced genetic diversity, making populations more susceptible to diseases and environmental changes.
3. The principles of artificial selection have been applied in agriculture, resulting in high-yield crops and livestock with desirable characteristics.
4. Unlike natural selection, where environmental pressures determine survival, artificial selection relies on human preferences and goals.
5. Examples of artificial selection include the domestication of plants like corn from teosinte and the variety of dog breeds that have been developed for specific tasks or companionship.

Review Questions

• How does artificial selection demonstrate similarities and differences compared to natural selection?
  • Artificial selection shares the fundamental principle of selective breeding found in natural selection, as both processes favor certain traits that enhance survival or reproductive success. However, a key difference is that artificial selection is driven by human choice rather than environmental pressures. This allows for rapid changes in traits, but it may also lead to unintended consequences such as reduced genetic diversity, which is less common in natural ecosystems influenced by natural selection.
• Discuss the potential advantages and disadvantages of artificial selection in agricultural practices.
  • Artificial selection can significantly enhance agricultural productivity by developing crop varieties and livestock breeds that yield higher outputs or possess desired traits like disease resistance. However, this practice can also have disadvantages, such as a decrease in genetic diversity within populations. Reduced genetic diversity can make crops and livestock more vulnerable to diseases and environmental changes, ultimately threatening food security if widespread problems arise.
• Evaluate the long-term impacts of artificial selection on biodiversity and ecosystem stability.
  • The long-term impacts of artificial selection on biodiversity can be significant. While it can promote specific advantageous traits within selected species, it often leads to a reduction in genetic variation across populations. This loss of genetic diversity can destabilize ecosystems as it may hinder species' ability to adapt to changing environments or resist diseases. Additionally, as certain species become dominant due to selective breeding, other species may face extinction or decline, further affecting ecological balance and resilience.

Related terms

natural selection:

A process in which organisms better adapted to their environment tend to survive and produce more offspring, leading to evolutionary change.

genetic variation:

The diversity in gene frequencies among individuals within a population, which is essential for both artificial and natural selection.

breeding programs: Structured methods used by humans to enhance desirable traits in plants or animals through controlled mating.