Melissa Hogenboom BBC News 24 Jan 13;
Most of the world's plant and animal species could be named before they go extinct, claim researchers.
Writing in the journal Science, the researchers said it could be achieved this century.
This is largely due to an increase in taxonomists - the people who describe species new to science.
Although there is an extinction crisis, the rates are lower than previously expected, the scientists report.
Discovering and naming the world's species is critical for their conservation and can be done with only a modest increase in effort, the researchers stated.
But they also recognised it will be difficult to maintain a high rate of discovery as it becomes harder to find rare species.
Previous overestimates of the number of species - some as high as 100 million, led some in the scientific community to believe that it would be impossible to name all the world's species before they go extinct.
Naming a species gives formal recognition to its existence, making conservation easier, said lead author, Associate Professor Dr Mark Costello, from The University of Auckland.
"We believe that with just a modest increase in effort in taxonomy and conservation, most species could be discovered and protected from extinction."
As more information on taxonomy is available to the public via the internet, amateur as well as professional taxonomists are increasing, especially in regions such as Asia and South America, which are rich in biodiversity.
"We've discovered three times more people now naming species than there were ever before. We're in the golden age of taxonomy," added Dr Costello.
He hopes that this increase will continue, and that the public become more involved.
There are currently around around 1.5 million species which have been named. Dr Costello and his colleagues estimate the total number species on Earth ranges from two to eight million.
"Overestimates of the number of species on Earth are self-defeating because they can make attempts to discover and conserve biodiversity appear to be hopeless," said Dr Costello.
Jean-Christophe Vie, deputy director of the International Union for Conservation of Nature species programme, disagrees with the review's conclusion that "species are more likely to be described than become extinct".
"Extinction is usually underestimated. It's more important to fight extinction than to describe or catalogue all species," he said.
"We can protect species even if we don't know all of them. I have no doubt we can catalogue all of life, and it would be useful, but we don't have the luxury of time."
"I am worried by the message implying that to conserve species you need to know everything about them. You can do a lot of protection even in the absence of knowledge."
To increase the time it takes to name the world's species, Dr Costello and colleagues recommend more taxonomists to be employed, increased financial support and international coordination in the scientific community to share expertise.
Professor Georgina Mace, from the Centre for Population Biology at Imperial College London, welcomes the analysis but also questions whether we really need to know the names of all species.
"Its excellent news, that taxonomic expertise is moving very effectively to tropical countries where most of the biodiversity on Earth is," she said.
She added that with sensible sampling, conservationists can prioritise effort on groups of species that are disappearing in the places most under threat.
"Once you've done that you can put in place conservation actions that will benefit everything there, whether named or not."
"It is part of our cultural responsibility to have looked at every single species of earth, but because it can be difficult to do, particularly the last few percent. We need to be quite strategic about the effort put into discovering, describing, monitoring and conserving."
The levels of investment needed to name all the species is very modest, in global terms, said Professor Ken Norris, director of centre for Agri-Environmental research at Reading University.
He added that many species play important functional roles in the way Earth works and the life support systems they provide.
"If we lose them, important functions of those systems - like purifying weather, providing fertile soils and clean air - might be damaged without us realising what we've lost," Prof Norris explained.
"Extinction isn't just about losing part of Earth's evolutionary history, it might also involve fundamental changes in the Earth's ecosystems that may have detrimental effects on mankind."
Naming species before extiction
The University of Auckland Science Alert 25 Jan 13;
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.
The current research is published in Science: Costello MJ, May RM, Stork NE. (2013) Can we name Earth’s species before they go extinct?
Most Species on Earth Could Be Recorded, Study Finds
Douglas Main LiveScience.com Yahoo News 7 Feb 13;
What strange creatures dwell in the rainforests, at the bottom of the ocean or even in plain sight in our cities? If we don't look, we'll never know, one group of researchers says.
A study published Jan. 24 in the journal Science suggests that discovering and recording all of Earth's biodiversity may not be as difficult as previously thought, and could be accomplished with a "realistic surge of effort," said study co-author Mark Costello, a researcher at New Zealand's University of Auckland. By spending between $500 million and $1 billion annually for the next 50 years, humans could describe most species on Earth, Costello told OurAmazingPlanet.
Costello and his two co-authors also calculated that extinction rates are not as high as many scientists previously thought. The study suggests that species are currently being discovered faster than they go extinct, contradicting a widely held tenant amongst scientists that the opposite is currently happening amidst the biggest mass extinction since the dinosaurs were wiped out tens of millions of years ago. Though some scientists welcome the focus Costello and his colleagues are placing on the need to catalog Earth's species, they don't necessarily agree with their conclusions.
How many species are there?
Estimations of the number of species that live on Earth vary considerably, from as few as 2 million to as many as 100 million species. Costello's paper suggests there are between 2 million and 8 million species, at the low end of many scientists' estimates. It is difficult to tell exactly how many species there are without counting them, of course; different environments (many little-studied) have different levels of biodiversity, making it difficult to come up with a global number, and little is known about remote environments like the deep sea, for example.
There are currently more than 1.5 million species described, but the exact number is uncertain due to overlapping descriptions of the same species, as well as the lack of digitization of many databases and collections, said Mike Novacek, the provost of science at the American Museum of Natural History in New York, who was not involved in the study. [Earth Quiz: Do You Really Know Your Planet?]
Although the amount of money Costello and his colleagues say will be needed to count Earth's species may seem like a lot, it pales in comparison to what we spend on sports, entertainment and space exploration. Knowing how many species are on Earth is vital to understanding life itself, Costello said.
"It's part of exploring our own planet. It is the first step in understanding ecosystems and as fundamental to biology as naming particles is to physicists, or describing elements is to chemists," he said.
Novacek said that he welcomed the paper's emphasis on recording species and conservation. "It's a cultural embarrassment that we know so little about life on this planet," he said. However, the paper's estimates of species extinction were a little low, he added.
Camilo Mora, a biologist at the University of Hawaii, went further, saying he thought the study significantly underestimated the number of extinctions occurring worldwide, making the current extinction crisis appear less worrisome than it is.
Extinction rates are also important to know because every organism serves a unique role in its ecosystem, which suffers when species are lost. Healthy ecosystems can make for cleaner water and air, as well as ensure the survival of important resources. Even people in cities and towns reap the benefit of far-flung biodiversity; for example, many modern drugs (like quinine, used to treat malaria) have originated from chemicals found in rainforest plants.
The study
The new study was a review of newly published research on extinction rates and discoveries of new species. Costello said that his team's approach was novel because it attempted to calculate global levels of biodiversity by looking at the sum of individual ecosystems the world over. Other calculations of extinction may have overstated the problem by taking local numbers and applying them globally, which Costello's team took pains not to do, he said. High levels of biodiversity in one patch of rainforest may not be paralleled in other areas of rainforest or temperate forest, for example, he said. [8 of the World's Most Endangered Places]
Costello's team also suggests that there are more papers than ever describing new species, thanks to the involvement of a growing number of scientists who don't typically specialize in taxonomy, as well as amateur scientists, he said. For that reason, the task of describing the world's species may not be as insurmountable as thought, he added.
Observed rates of extinction haven't been as high as predicted by some, due in part to better conservation efforts worldwide and the survival of animals in "secondary" habitats like agricultural areas, Costello said. Species can hang on in these degraded habitats longer than expected, giving conservationists a chance to save them before they disappear, he said. Pristine habitats are nevertheless vital to protect, he added.
Controversy
But not everyone agrees with the assessments and conclusions of Costello and his co-authors.
Even the median rate of extinction suggested in Costello's paper — at 25,250 per decade — is disturbing for the planet, Novacek said, while the lower bound of the estimate (500 extinctions per decade) sounded a little low and was "optimistic," to say the least.
Mora's criticism went further: "They paint a very nice glossy picture of the reality of what's happening out there," Mora told OurAmazingPlanet. "But it doesn't represent the reality."
For example, Mora said his "mind was blown" (in a negative way) by the 500-extinctions-per-decade suggestion. Habitat loss alone leads to 25,000 extinctions per year, he said. "And that's just because of habitat loss. Now start adding all the stressors — like climate change, invasive species, pollution — and the number is likely to go a lot higher," he said.
Mora also disagreed with the paper's assertion that the number of qualified taxonomists is growing worldwide. While there may be more authors of papers describing new species, many of these consist of amateurs or nontaxonomists who do not have the necessary expertise to provide leadership in the field, he said. There are fewer full-time positions for taxonomists and many experts in their fields aren't being replaced once they retire, Mora said, a view with which Novacek agreed. [Amazing Species Discovered in 2012]
Extinction crisis
All sides could agree, however, that we are in the midst of an enormous extinction crisis, the largest since the disappearance of the dinosaurs 65 million years ago, and that we must do more to record and conserve these species before they vanish. "The dinosaurs disappeared because of an asteroid, and in this case we are the asteroid," Novacek said.
All sides agreed that humans could — and should — record most species, although opinions on exactly how much effort or money it might take differed. In the short-term, smaller efforts could make a big difference, Costello said.
"We estimate the backlog in undescribed species in collections could be cleared by hiring 500 new taxonomists for 10 years," he said, which would cost about $5 million per year, and help pave the way for the more expensive and time-consuming process of describing new species found in the wild.
"In the end, there's going to be some controversy and dialogue about these numbers, but I'm glad the paper is coming out and that the issue [of extinction and conservation] is being discussed, because it's so important," Novacek said.
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