Biodiversity

This lesson covers biodiversity — the variety of living organisms in an ecosystem — as required by the Edexcel GCSE Combined Science specification (1SC0). You need to understand what biodiversity is, why it is important, the threats to biodiversity and the methods used to conserve it.

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What Is Biodiversity?

Biodiversity is the variety of all the different species of organisms on Earth, or within a particular ecosystem. It includes:

• The number of different species present (species richness)
• The abundance of each species (how many individuals of each)
• The genetic variation within species

A healthy ecosystem typically has high biodiversity — many different species, each with a stable population.

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Why Biodiversity Matters