Situated off the north-east tip of Somalia, few people are aware that the 8,500 square kilometre island of Socotra belongs politically to Arabia. For eight months of the year it's almost inaccessible by boat, due to treacherous seas and monsoon storms.

Yet scientists believe that Socotra's unique environment may harbour hitherto undiscovered species of plan and marine life. Hence this week, a self-contained expedition will set sail from the Arabian Gulf to spend two months on and around this Indian Ocean island.

The project has been called the Voyage of Discovery and its leader, Jonathan Ali Khan, told the BBC that the potential yield from Socotra's homeopathic plants could run to hundreds of millions of dollars. He said that since the island has been separated from Africa for 70 million years it contains species found nowhere else in the world.

At a cost of $80,000 the expedition will be operating from two self-contained dive-boats, one of which will be towed 600 km from the coast of mainland Arabia. The expedition will not be without its hazards.