GCSE Combined Science (AQA)

622 videos | 38 hours

Mass Extinction

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Inheritance, Variation and Evolution The Development of Understanding of Gentics and Evolution

Mass Extinction

1:23 Pressure on Organisms
Spec 4.6.3.6
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  • Mass extinction is defined as an event that causes the extinction of multiple species.
  • Specific knowledge of an event is not required for the exam, but understanding the definition of mass extinction is necessary.
  • An example of a mass extinction event is the extinction of dinosaurs.
  • About 66 million years ago, a 10-kilometer-wide asteroid struck Mexico.
  • The impact created a 180-kilometer-wide crater and released a cloud of superheated dust, ash, and steam.
  • This cloud blocked sunlight, leading to a significant drop in photosynthesis.
  • The reduction in photosynthesis decreased food availability throughout the food chain.
  • The lack of food and changes in temperature put immense pressure on dinosaurs and other species.
  • These conditions led to the mass extinction of many species, including dinosaurs.

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