Summary
Change in the inherited characteristics of populations over successive generations.
In depth
Evolution is descent with modification. It is observable as changes in allele frequencies in populations, and over long periods explains the diversity of life from a common ancestor. The main mechanisms are natural selection, genetic drift, mutation and gene flow.
The theory is supported by independent lines of evidence: fossils, comparative anatomy, embryology, biogeography and molecular biology.
Common mistake: evolution has no goal or foresight; it does not make organisms 'better', only better matched to their local conditions.
Frequently asked questions
What is Evolution?
Change in the inherited characteristics of populations over successive generations.
Which area of biology covers Evolution, and how advanced is it?
Evolution is one of the 53 topics in Evolution. It is rated Beginner, so it suits learners who are starting out in biology. Related topics in this area include Natural Selection, Charles Darwin, Neutral Theory.
What should I learn before Evolution?
Evolution is a Beginner topic, so no earlier topic is required. Other Beginner topics in Evolution that pair well with it include Natural Selection, Charles Darwin, Adaptation.
What topics are related to Evolution?
The closest topics to Evolution are Natural Selection, Charles Darwin, Neutral Theory, Adaptation. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Evolution?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Evolution. To practise the whole of Evolution, use the Evolution quiz.
How is Evolution different from Natural Selection?
Evolution: Change in the inherited characteristics of populations over successive generations. Natural Selection: Individuals with traits better suited to their environment survive and reproduce more, passing those traits on. Read both side by side and note what each one explains.
What is a common mistake about Evolution?
Evolution has no goal or foresight; it does not make organisms 'better', only better matched to their local conditions.
How should I study Evolution step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Natural Selection and explain the difference aloud. Finally, take the Evolution quiz and come back to this page for any question you miss.