Finding Species Before They Disappear Forever
The Anguilla Bank skink, a Caribbean species discovered along with 23 others in 2012, is vulnerable to extinction. (Photo: Karl Questel)
My latest, for Smithsonian magazine:
One night in June, 2012, entomologist Piotr Naskrecki was exploring a forest on Mt. Gorongosa in Mozambique, when he spotted a new species out of the corner of one eye. He’ll publish the first scientific description of his find, a katydid, later this month in the journal Zootaxa. But its debut will almost certainly also serve as its death notice: When Naskrecki went back in 2013, hungry farmers had already turned that stretch of forest into corn fields.
We live in the middle of what scientists say is the Earth’s sixth great extinction event. Number five was the one that got the dinosaurs. Number six started back about 10,000 years ago, when human hunters and climate change wiped out mammoths and other megafauna. It has lately accelerated as humans have pushed into the farthest corners of the planet. Biologists must now sometimes race to discover species even as the chainsaws are cutting down the forest around them. Speed is the new priority, to make discovery happen ahead of extinction—even perhaps in time to prevent extinction.
Scientists have so far described almost two million species. But it has taken them 250 years to get there. They now describe about 18,000 new species every year, and conservationists say that’s not nearly fast enough. A 2011 study in the journal PLoS Biology conservatively estimated that there are 8.75 million species on Earth, with more than 85 percent of them unknown to science. The authors calculated that, at the current rate of species discovery, it could take hundreds of years and $364 billion to describe them all. But long before then–in fact, sometime in the next century–75 percent of them will have gone extinct without being described. But that just makes “attempts to discover and conserve biodiversity appear hopeless,”according to the authors of a more recent study in Science. They authors figured that, by ramping up the rate of discovery tenfold, scientists could complete the catalogue of life on Earth in just 50 years.
Quentin Wheeler, director of the International Institute for Species Discovery, argues for a “NASA-scale mission to map the biosphere once and for all.” It could boost the rate of new species to 200,000 a year, he says, by funding 2000 existing taxonomic specialists, each supported by a staff of three, to devote themselves full-time to producing 100 species descriptions a year. That’s roughly the model the National Science Foundation used for its short-lived Planetary Biodiversity Inventory. It might cost $1 billion a year, he says, “but the United States spends $150 billion just responding to invasive species.”
Genetic techniques are already speeding up the process of discovery. In Madagascar, for instance, ant specialist Brian Fisher takes an assembly line approach to collecting and analyzing a study site, sending off batches of undescribed insects for DNA “barcoding,” to get a sense of how many unknown species may live there. In Southeast Asia, the intrepid pioneers of a new technique called iDNA (for invertebrate DNA) go a step further, barcoding the DNA in the blood of land leeches picked off their own bodies, to see what other mammals and birds the leeches have been feeding on.
Digital technology has also begun to democratize taxonomy, bringing experts and amateurs together through Internet sites like Fisher’s Antweb.org and even Facebook, to crowdsource the preliminary sorting of specimens. The literature of species discovery is also becoming more widely available via web sites like the Encyclopedia of Life. And later this year, researchers from anywhere in the world will be able to go online and examine the defining “type” specimens of a species without ever leaving home. Instead, they’ll use remotely-operated digital microscopes now being installed at the Smithsonian’s National Museum of Natural History and sister museums in London and Paris.
The actual description of a potential new species still requires tedious and time-consuming comparisons with known species, and a lot of specialized taxonomic expertise. But trained taxonomists increasingly come from the tropical nations where much of the discovery is now happening, and in Europe amateurs taxonomists now contribute 40 percent of the species descriptions.
A more complete catalog of life on earth would create a baseline for recognizing changes in our environment, and it would provide an enormous boon to biomimicry—the highly profitable human knack for devising everything from medicines to gadgets based on models from the natural world.
A catalog of all the life on earth would help us respond to environmental changes, such as invasions of nonnative species, and would boost the quest for medicines and other materials extracted from or inspired by living things. To drive home the need for speed, biologists tell the story of a chemical found in an ancient swamp forest tree in Borneo. It stopped HIV cold, but when rsearchers raced back for more samples, a stump remained where the tree had stood. If a few surviving specimens had not turned up in a botanical park, the experimental drug Calanolide A might not exist today.
