A portion of the State of Rondonia, Brazil in 1975. (Image courtesy of USGS)

What’s in a number? Well, quite a lot when it comes to saving species. Much of the work done by scientists to justify conservation measures and recommendations relies on combining theoretical models with field data.

So you can imagine the furor that erupted a week ago when the prestigious journal Nature published a paper proclaiming that one of the key theoretical models is “always wrong.” Authored by Fangliang He and Stephen Hubbell, the paper tests a mathematical correlation between the number of species in an area and the size of the area. The authors argue that the standard method used to extrapolate extinction rates from loss of habitat area always overestimates the predicted number of extinctions. They conclude that species “are not in quite as serious trouble right now as people had thought.”

SavingSpecies founder and Advisory Board member Stuart Pimm published a strong rebuttal of the paper in his National Geographic blog. It’s a “sham” says Dr. Pimm, to claim that the extinction crisis is overblown. Several distinguished scientists in addition to Pimm have pointed out “deep flaws” in the paper. For one thing, the Nature authors only consider species immediately driven extinct by deforestation. But that’s not very realistic. Most species are distributed unevenly in “island” patches so they often linger after significant habitat loss, but in small populations that will inevitably go extinct.

The exact same portion of the State of Rondonia, Brazil in 1986. (Image courtesy of USGS)

But this is more than an academic disagreement. By claiming that a core tenet of conservation “always overestimates” extinction, Hubbell and He pave the way for an army of anti-conservationists to justify their business as usual position. If the theory says things aren’t as bad as we thought, why not just put off any tough decisions? The authors themselves anticipate that their results would be “falsely construed in some quarters.” Indeed, Wired blogger Sheril Kirshenbaum voices precisely this concern: “I’m most concerned that [the authors’] conclusion will be misused by special interest groups and policymakers who want to minimize conservation efforts.”

Such concerns are well-founded. Already, the anti-conservationists and climate-deniers are busy citing He and Hubbell. For example, one blog says that “the discrepancies … suggest a large and well-planned scam as huge amounts of funds are allocated by government, corporate and individual donors towards conservation of wildlife … in the name of preventing extinction of species.” Outrageous accusations aside, many media have failed to represent the paper correctly, exactly as the authors themselves anticipated. For example, according to Australia’s News.com, “the pace at which humans are driving animal and plant species toward extinction through habitat destruction is at least twice as slow as previously thought.”

The same portion of the State of Rondonia, Brazil in 1995, twenty years after the first. (Image courtesy of USGS)

One commenter on Sheril Kirshenbaum’s blog post suggests that it is “nothing to do with the paper” that “anti-conservation groups are mis-interpreting the findings and twisting their results to suit their agenda.” But such a defense is misguided. Science is a societal enterprise. Scientists do not work apart from society. Scientists have a moral and ethical duty to consider carefully the consequences of their work. In this instance, He and Hubbell abdicated their responsibility in favor of a sensationalist headline. This is not about academic freedom or “truth,” it is about the power of words. As Pimm says in his blog post, “Wording matters. It always does.” And now He and Hubbell’s words, from an authoritative scientific journal, are being used to unravel years of toil by dedicated scientists and conservationists. Are He and Hubbell are ready to defend that consequence of their work?

FURTHER READING

Species Extinction Rates Have Been Overreported, New Study Claims
Numbers flap has minor implications for global extinctions
Scientists Clash on Claims Over Extinction ‘Overestimates’
Extinction rates have NOT been over-estimated