for National Geographic News
Conservation biologists have recruited sophisticated satellites to help discover and protect unknown species before they disappear.
Sensors on the satellites can collect information such as the vegetation, climate, and topography of remote and unexplored regions, explained Christopher Raxworthy, the associate curator of herpetology at the American Museum of Natural History in New York.
In computer models these data are combined with information on habitats in which certain species thrive. The combination allows scientists to predict regions where speciessome known, others notare most likely to be found.
These data are combined with the coordinates of sites where a species is known to occur. Then, using computer programs, scientists analyze the information to predict other areas where the species might live.
Field scientists can then travel to the targeted area and search for the species. The technique helps eliminate some of the guesswork traditionally involved in conservation biology, speeding the pace of discovery and protection.
"Habitat loss in many regions is occurring so fast that some species may be lost before we find them," Raxworthy wrote in an e-mail to National Geographic News.
Raxworthy and his colleagues are using satellite data to help predict the locations of chameleons, lemurs, and other species on the island nation of Madagascar, located off the east coast of Africa.
"This next rainy season we will be testing these predictions," Raxworthy said. (The rainy season in Madagascar runs from November through April.)
This type of testingcalled ground truthinginvolves visiting regions that the computer models predict are homes to certain species and verifying the species' presence the old-fashioned way.
Ground truthing is essential to validating the satellite data, according to Woody Turner, a scientist with NASA's Science Mission Directorate in Washington, D.C.
"I believe it was Mark Twain who said there are three kinds of lies: lies, damned lies, and statistics," Turner said. "To that, I'd perhaps add a fourth: remote-sensing observations that have not been adequately ground-truthed."
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