Why is vegetation on Socotra Island so unique?

Socotra is located between the Guardafui Channel and the Arabian Sea. It is the largest of four islands of Socotra. The island is isolated, and home to a high number of endemic species, up to a third of its plant life is endemic. The island is home to at least 700 different endemic species, which are found nowhere else on earth.

One of the most extraordinary of Socotra's plants is the dragon's blood tree. It is umbrella shaped. There are also cucumber trees. The vegetation on the island has many practical uses, which include medicinal and cosmetics. The island also has several species of birds, one called The Socotra Starling.

Isolation. Isolation is responsible for most of it. Socotra was once a part of the geological mass of Gondwana. It has been an island for 25 million years now. Geologically speaking, Socotra separated from Gondwana during the Miocene era.

This separation began the unique vegetation trend for the island. As the world shaped itself to as it is today, Socotra stood and watched. Socotra is a dry desert-like island with average temperatures ranging 25-30 C all year around. The desert conditions also contribute to its uniqueness.

Even though the nearest landmass is a mere 300 km the ocean in the middle meant that plant species did not get propagated elsewhere and hence became endemic to the region and evolved for 25 million years specifically for Socotran climate. As of today, 307 species of plants are found nowhere on the planet except Socotra island.