Variation and evolution

Variation and evolution are fundamental concepts in biology that explain the diversity of life on Earth. Variation refers to the differences between individuals of the same species, which can be caused by genetic factors (e.g., mutations, sexual reproduction) or environmental factors (e.g., diet, climate). Evolution is the process by which species change over time through natural selection, where individuals with advantageous traits are more likely to survive and reproduce, passing those traits to the next generation. This topic is essential for understanding how species adapt to their environments and how new species arise.

In the WJEC GCSE Biology course, you will explore the causes of variation, including genetic and environmental influences, and how variation is the raw material for natural selection. You will also study the work of Charles Darwin and Alfred Russel Wallace, who independently developed the theory of evolution by natural selection. Key evidence for evolution includes the fossil record, comparative anatomy (e.g., homologous structures), and molecular biology (e.g., DNA comparisons). Understanding these concepts is crucial for explaining antibiotic resistance in bacteria, the development of new species, and the interconnectedness of all life.

This topic builds on earlier work in genetics and inheritance, and it links to broader themes such as biodiversity, conservation, and the impact of human activity on evolution. By mastering variation and evolution, you will gain a deeper appreciation for the mechanisms that drive the diversity of life and the importance of preserving it.