Variation
Variation is the differences between individuals of the same species, caused by genes, the environment or both.
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Variation is the differences between individuals of the same species, caused by genes, the environment or both.
- Genetic variation comes from sexual reproduction
- Environmental variation includes scars and diet
- Continuous variation shows a smooth range
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is Variation?
Within Biology, which covers cells, the human body, genetics, evolution, plants and ecosystems: the science of living things, this topic explains Variation. 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 Variation in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding Variation helps you explain how living things stay alive and respond to their surroundings, which is central to biology exams.
Variation in detail
Variation is the differences between individuals of the same species. It may be genetic, caused by different alleles inherited from the parents, environmental, such as a plant growing taller in good light, or a combination, such as human height.
Continuous variation has a range of values, such as height, whereas discontinuous variation has distinct categories, such as blood groups. Sexual reproduction, mutation and random fertilisation create genetic variation. Variation is essential for natural selection, as it allows some individuals to survive better when the environment changes.
How the interactive helps you understand Variation
Watch the bar chart in the interactive. Use any sliders or buttons it offers to change the values and see how the bar chart 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 Variation.
Real-life uses and examples
- Structure a longer answer about Variation by moving from definition to example to consequence.
- Explain how Variation helps a living thing stay alive, using a plant or animal example.
- Connect Variation to health, food and medicine in everyday life.
Common mistakes to avoid
- Listing the steps of a process without saying how one step causes the next.
- Using everyday words, such as “energy” or “bad”, without their scientific meaning.
- Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.
Frequently asked questions about Variation
What is Variation?
Variation is the differences between individuals of the same species, caused by genes, the environment or both.
What are the most important points about Variation?
The main points are: Genetic variation comes from sexual reproduction; Environmental variation includes scars and diet; Continuous variation shows a smooth range.
Why is Variation useful?
Understanding Variation helps you explain how living things stay alive and respond to their surroundings, which is central to biology exams.
How can I practise Variation?
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 Variation?
Related topics in Biology include Evolution, Selective Breeding, Ecosystems and Habitats.