Natural Selection
Natural selection is the process by which individuals with helpful features survive and breed more, so those features become more common.
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Natural selection is the process by which individuals with helpful features survive and breed more, so those features become more common.
- Variation exists in a population
- The best adapted survive
- They pass on their alleles
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is Natural Selection?
Within Biology, which covers cells, the human body, genetics, evolution, plants and ecosystems: the science of living things, this topic explains Natural Selection. Biology topics show how living things work, from the cell up to whole ecosystems, with models you can explore step by step.
Check that you can explain Natural Selection in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding Natural Selection helps you explain how living things stay alive and respond to their surroundings, which is central to biology exams.
Natural Selection in detail
Natural selection is the process by which organisms best adapted to their environment survive and reproduce, passing on their advantageous alleles. Darwin's theory has these steps: there is variation in a population, more offspring are produced than can survive, there is competition (a struggle for survival), individuals with beneficial characteristics are more likely to survive and breed, and the alleles become more common over generations.
Examples include the peppered moth during the Industrial Revolution and antibiotic-resistant bacteria. Natural selection is the main mechanism of evolution and explains how species become adapted to their surroundings.
How the interactive helps you understand Natural Selection
Watch the population model in the interactive. Use any sliders or buttons it offers to change the values and see how the population model responds.
Before you change anything, predict the result. Then change one value at a time and check whether your prediction was right. This is a quick way to build a correct mental model of Natural Selection.
Real-life uses and examples
- Explain how Natural Selection helps a living thing stay alive, using a plant or animal example.
- Connect Natural Selection to health, food and medicine in everyday life.
- Use Natural Selection to interpret a diagram, graph or microscope image from a practical.
Common mistakes to avoid
- Using everyday words, such as “energy” or “bad”, without their scientific meaning.
- Listing the steps of a process without saying how one step causes the next.
- Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.
Frequently asked questions about Natural Selection
What is Natural Selection?
Natural selection is the process by which individuals with helpful features survive and breed more, so those features become more common.
What are the most important points about Natural Selection?
The main points are: Variation exists in a population; The best adapted survive; They pass on their alleles.
Why is Natural Selection useful?
Understanding Natural Selection helps you explain how living things stay alive and respond to their surroundings, which is central to biology exams.
How can I practise Natural Selection?
Open the interactive at the top of this page and change the controls one at a time. Predict the result before each change, then take the three-question quiz. A score of two or more marks the topic as complete on this device.
Which topics are related to Natural Selection?
Related topics in Biology include Extinction, Cloning, Energy Transfer and Pyramids.