IB ESS — Topic 3.2

Natural selection, variation and speciation

Topic 3.2 covers the mechanisms of evolution through natural selection, genetic variation, and speciation. Students study how populations change over time, the role of geographic isolation, and how new species form — connecting biological theory to conservation.

Sub-topics in Topic 3.2

3.2.1Natural selection

Study Topic 3.2: Natural selection, variation and speciation

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