Classification and Extinction

This lesson covers how organisms are classified into groups and the causes of extinction. For AQA GCSE Biology, you need to understand the Linnaean classification system, the three-domain system proposed by Carl Woese, and the factors that can lead to species becoming extinct.

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What Is Classification?

Classification is the process of organising living organisms into groups based on their shared characteristics. It helps scientists to:

• Identify organisms
• Understand evolutionary relationships between species
• Communicate clearly about organisms using a universal system
• Predict characteristics of newly discovered species based on their classification group

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The Linnaean Classification System

The classification system used today was developed by the Swedish scientist Carl Linnaeus in the 18th century. He organised organisms into a hierarchy of groups, from the largest and most general to the smallest and most specific.

The Classification Hierarchy