for National Geographic News
A giant tortoise species from the Galápagos Islands thought to be extinct since the 1800s may not be gone after all, according to new research findings.
The very same history that wiped out its populations may have inadvertently saved it.
Scientists have discovered that genes from the Floreana tortoise, which Charles Darwin studied on his visits to Floreana Island in 1835, can be found in modern Galápagos tortoises.
Experts now believe a concentrated breeding program could resurrect the species.
Yale University researchers have been visiting the islands, off the coast of Ecuador, since the mid-1990s, when they first noticed tortoises with mixed appearances—some of them strikingly similar to supposedly extinct species.
The 15-year effort was partially funded by the National Geographic Society's Committee for Research and Exploration. (National Geographic News is owned by the National Geographic Society.)
The results appear in this week's issue of the Proceedings of the National Academy of Sciences.
Food and Lamp Oil
Tortoises on the Galápagos Islands helped fuel evolutionary biologist Charles Darwin's theory of natural selection.
He found different tortoise sizes and shapes corresponded to survival in various types of island habitat.
Some of the reptile species are rounded or dome-shaped, while others are saddlebacked, with the front part of their shells elevated. Past research has suggested the saddlebacked adaptation is for feeding on taller plants in dry habitats.
When Darwin visited the Galápagos Islands in 1835, he noticed that the tortoises were being heavily exploited as food. One species in particular—a saddlebacked variety from the island of Floreana—was also being hunted for its oil, which was valued as lantern fuel.
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