The tortoise is threatened with extinction in Zanzibar because they are being taken away for sale to ships in Dar es Salaam harbour. But now, according to the ‘Business Times’, they are to be provided with special devices to be implanted in the shells which will respond to the touch and so trigger a signal directly to a monitoring centre to show that the animal is probably in trouble. It is one of the new technologies being used to protect endangered species the world over.