QUITO, Ecuador (AP) — Scientists in Ecuador's Galapagos islands are hoping to restore a tortoise species believed extinct since the 1800s.

The Chelonoidis elephantopus lived on Floreana Island and was captured by seamen in large numbers for food during long journeys across the Pacific. The species is thought to have disappeared shortly after Charles Darwin's celebrated visit to the treasured archipelago.

But a group of international scientists who collected 1,700 blood samples from tortoises on Isabel Island farther north during a research expedition in 2012 made a surprising discovery: 80 had...