How Many 'Extinct' Species Are Still Out There?
Earlier this week, Chelonoidis elephantopus, a species of giant Galapagos tortoise thought to have been extinct for the past 150 years, was declared alive and well. Though the scientists didn't spot the lumbering beasts themselves, they did analyze the genes of the nearly 2,000 living giant tortoises living on the island. What they found was astonishing: 84 of the living tortoises shared genomes that could only be attributed to the supposedly extinct species, with breeding in some cases having occurred in the last 15 years. With giant tortoises regularly living past the century mark, the odds were overwhelming that a small population had survived.
“At first, we didn’t know where these tortoises had come from. We called them aliens,” said Yale researcher Giselle Caccone to ABC News. “When we did the analysis, we said, uh, oh, those ‘aliens’ were from what we thought was the extinct population.”
This isn't the first time a large, slow-footed creature has come back from the dead. Although Westerners first learned about the giant panda in 1869, it wasn't spotted in the wild by scientists until well into the 20th century, leading to speculation that it had gone extinct. And the slow-moving coelacanth, perhaps the most extreme example of a Lazarus species, was only discovered by fisherman this century after having been left for dead for the past 65 million years.
But this is the age of GPS, cell phone cameras, and Google maps. Shouldn't we be nearing the end of the age of rediscovery?
If anything, technology is demonstrating how little we still know about the planet. Just last week, Antarctic researchers reported that they had discovered a wide range of previously unknown species like albino octopae and yeti crabs living near a heat vent 8,500 feet under the ocean. Without a remote-operating vehicle and a camera that could survive such intense pressure and variations in temperature (vents can get up to 720 F), such discoveries would be impossible.
With mass deforestation, urbanization, and overpopulation, it seems inevitable that someday our only new discoveries will be microscopic creatures living in the most hostile of environments. But places like the Galapagos, which offer rare sanctuary for animals on our shrinking planet, remind us that doesn't have to be the case.