Open Borders Threaten Unique Canary Islands

It rains little on this island. There are no natural rivers, and the air is full of the dry heat of the nearby Sahara. But in a ravine on the island's northern tip, tree limbs drip with water and a tropical forest flourishes, sustained almost entirely by condensation from the low-lying clouds regularly pinned against the mountainside. The area, called Cruz del Carmen, is only one example of the unusual evolutionary habitats on the Canary Islands that fascinated Charles Darwin more than 100 years ago, and that today reveal a new species or subspecies to scientists an average of once every six days...