Critical Thinking Questions
17. Describe the evidence for the cause of the Cretaceous–Paleogene (K–Pg) mass extinction.
18. Describe the two methods used to calculate contemporary extinction rates.
19. Explain how biodiversity loss can impact crop diversity.
20. Describe two types of compounds from living things that are used as medications.
21. Describe the mechanisms by which human population growth and resource use causes increased extinction rates.
22. Explain what extinction threats a frog living on a mountainside in Costa Rica might face.
23. Describe two considerations in conservation preserve design.
24. Describe what happens to an ecosystem when a keystone species is removed.
