What you’ll learn7 learning objectivesChoose one objective for a focused lesson, or study the complete topic.3.2.1Threats to biodiversity• Direct: overharvesting, poaching, illegal pet trade• Indirect: habitat loss, climate change, pollution, invasive alien speciesSyllabus objective3.2.2Multiple human impacts• Most ecosystems subject to multiple impacts• Effects amplified when combinedSyllabus objective3.2.3Invasive alien species• Reduce biodiversity through competition, predation, diseases/parasitesSyllabus objective3.2.4IUCN Red List• Global conservation status assessment• Based on: population numbers, rate changes, breeding potential, geographic range, threats• Status ranks: least concern (LC) to extinct (EX)Syllabus objective3.2.5Conservation status benefits• Publicizes species vulnerability• Allows selection of conservation priorities and management strategiesSyllabus objective3.2.6Species case studies• Extinct species due to human activity• Critically endangered species• Species improved by interventionSyllabus objective3.2.7Tragedy of the commons• Overexploitation of shared natural resources• Tension between individual self-interest and sustainable development• Examples: fish stocks, ocean plastic pollutionSyllabus objective