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IB Biology SL A4.2.8 Edge of Existence Programme Questions

Practise IB Biology SL A4.2.8 by using programme descriptions and maps to explain why globally endangered, evolutionarily distinct species receive conservation priority.

Syllabus
First assessment 2025
Course
Biology SL
Level
SL

Exam points

  • Explain how EDGE combines global extinction risk with evolutionary distinctiveness to prioritise species for conservation.
  • Interpret an EDGE programme description or distribution map to justify conservation attention for species with few close relatives.

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Study A4.2.8—EDGE of Existence programme conceptsOpen the corresponding Concept lesson for explanations, examples and exam connections.

IB Biology SL A4.2.8 Edge of Existence Programme Questions question 1

[Maximum number: 2]

Describe the role of the EDGE of Existence programme.

Chimpanzees and bonobos are different species of primate. It is thought that neither species can swim. The map shows the relative locations of chimpanzees and bonobos in Africa.

Figure for Question IB Biology SL A4.2.8 Edge of Existence Programme Questions question 1 — IB Biology SL

Evidence suggests that the level of the Congo River was lower during one period in the past. At this time, chimpanzees could have migrated across.

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