As reported in your News story “Should conservation biologists push policies?” (Nature 442, 13; 2006), academics are reluctant to demand the implementation of schemes to halt and reverse the biodiversity crisis. Conservation scientists seem to fear that taking a position would mean appearing biased, and that this would be better left to others.

Using science to conserve biodiversity does not require a biased opinion: it simply requires belief in the results. There is ample evidence showing that ecosystem, species and genetic diversity are critical for mankind's well-being, and that biodiversity is declining.

Conservation scientists should follow the path of Richard Doll, who revealed that smoking causes lung cancer (R. Doll and A. B. Hill. Br. Med. J. 2, 739–748; 1950) and then became active in advocating changes in public-health policies — without undermining his academic credibility. If Doll, and later his colleague Richard Peto, had adopted a 'back-seat' attitude and not lobbied against the tobacco industry, many more lives would be claimed by lung cancer today than is the case.