Claims that most species will go extinct before they can be discovered have been debunked in the latest issue of Science, by researchers from The University of Auckland, Griffith University, and the University of Oxford.
The scientists show that the claims are based on two key misconceptions: an over-estimation of how many species may exist on Earth, and the erroneous belief that the number of taxonomists (people who describe and identify species) is declining.
"Our findings are potentially good news for the conservation of global biodiversity," says lead author Associate Professor Mark Costello from The University of Auckland's Leigh Marine Laboratory, who published the work with Professor Nigel Stork from Griffith University and Professor Bob May from Oxford.
The authors propose that there are 5 +/- 3 million species on Earth – far fewer than has been widely believed – of which 1.5 million species have been named. This re-affirms previous estimates by the three authors, which spanned the upper and lower reaches of this range.
"Over-estimates of the number of species on Earth are self-defeating because they can make attempts to discover and conserve biodiversity appear to be hopeless," says Dr Costello. "Our work suggests that this is far from the case. We believe that with just a modest increase in effort in taxonomy and conservation, most species could be discovered and protected from extinction."
The authors conclude that there have never been so many people describing new species – including professionals and amateurs, the number may near 50,000. And the community continues to grow, in large part due to the development of science in Asia and South America, regions that are rich in biodiversity and where many new species are being discovered.
While the research suggests that species are more likely to be discovered than to go extinct, the authors do not underplay the seriousness of the threats to species and their habitats. The combination of over-hunting, habitat loss and climate change, now occurring at both local and global scales, mean that extinction rates could increase very rapidly in the future.
Dr Costello says that the discovery and naming of species is critical to their conservation. Naming a species gives formal recognition to its existence, making its conservation far easier. The process of discovery, including exploration of remote and less studied habitats, also provides the evidence to underpin conservation efforts.
Amongst the authors' recommendations to increase the rate of species discovery are: getting more people involved in the work; international coordination of exploration and specimen collections; the development of freely available online databases; and financial support from governments and other organisations for these efforts.