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Some people argue that wildlife conservation should focus the whole ecosystems(生态系统) instead of single species. Others support the umbrella method — by (live) in a celebrity species' habitat, smaller creatures (protect) as well. The thing is, that only works in some (situation). Take the beloved giant panda for example. By putting so much effort into the (nation) icon, China has at least partially protected many of the native forest birds and mammals in the panda's habitat, such as the endangered golden snub-nosed monkey, says Duke University conservationist Stuart Pimm.
On other hand, the endangered purple frog, (find) only in the Bengal tiger's range of India's Western Ghats, has not benefited from massive investments in the tiger's habitat. That's because the purple frog needs to grow — land with fast-flowing streams and largely free of roads — is different from the things that the tiger needs.
Pimm also offers these words of caution: that even (careful) made, supposedly scientific conservation methods may have faults — and may provide "an excuse not (make) tough decisions about conservation."