This deep dive covers What Is Biodiversity? within Biodiversity and Human Impacts for GCSE Biology. Topic 5: Biodiversity and Human Impacts on Ecosystems It is section 2 of 16 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.
🔬 What Is Biodiversity?
Biodiversity refers to the variety of all different species of organisms on Earth, or within a particular ecosystem. It has two key dimensions:
- Species richness — the total number of different species present in an area
- Species evenness — how evenly distributed those species are (a habitat with 10 species all equally common is more biodiverse than one dominated by a single species)
A tropical rainforest has extremely high biodiversity — thousands of species of insects, plants, birds, and fungi per square kilometre. A wheat field managed by humans has very low biodiversity — usually a handful of species across a huge area.
Biodiversity matters because ecosystems with more species are more resilient. Think of it like a game of Jenga: the more blocks you remove, the less stable the tower. Remove enough species and the whole ecosystem can collapse.
Practice questions for Biodiversity and Human Impacts
What is the best definition of biodiversity?
Explain why deforestation leads to a reduction in biodiversity.