1. Explain why the passenger pigeon became extinct.
2. Contrast the three types of extinction.
3. Define endangered species. (Also see G6)
4. Define threatened species. (Also see G18)
5. List the characteristics that make some species more vulnerable to than others
to ecological and biological extinction. (See fig. 12-4)
6. Discuss the three reasons that biologists consider extinction rates of 0.1-1%
to be conservative estimates.
7. Give an estimate of the time required to rebuild the biodiversity that humans
are likely to destroy during this century.
8. Discuss the various reasons why humans should preserve wild species.
9. Discuss the concept of the intrinsic value of species.
Read the section on biophilia and express your opinion of the concept.
10. Give the greatest threats to wild species, and give several examples. (Also
see fig. 12-7)
11. Explain the concept of habitat fragmentation and explain why it can lead
to extinction of some wild species.
12. Explain why conservation biologists view the significant decline in bird
populations as an early warning of the greater loss of biodiversity to come.
13. Explain why nonnative species can drive native species into extinction.
(Also see fig. 12-9)
14. How can the threats from nonnative species be reduced?
15. Discuss the primary principles of the Endangered Species Act.
16. Explain why almost half of the recovery plans mandated by the ESA have not
been implemented.
17. Discuss the issues associated with property rights and the ESA.
18. Discuss the issues associated with weakening or strengthening the ESA.
19. Discuss the different sanctuary approaches to protecting wild species.
20. List some of the problems associated with each approach.