J Madambikattil Sasi and Biju Dharmapalan

Everyone is familiar with islands, which are usually land areas surrounded by water. But have you ever heard about “Sky Islands”? Though it rhymes with sky, there is nothing related to sky or space. Sky islands are one of the fragile and unique ecosystems on our planet. They are isolated mountains surrounded by radically different lowland environments. The term was initially used to refer to those isolated ecosystems found on the Mexican Plateau by herpetologist Edward H Taylor in 1943. However, the concept of “Sky Islands” was popularised by nature writer Weldon Heald in his book Sky Island, published in 1967. In more recent scientific contexts, Indian evolutionary biologist VV Robin is credited with identifying the sky island ecosystems of the southern Western Ghats and has researched the evolution of birds in these unique areas. According to VV Robin, “Sky islands are different from oceanic islands; here intervening valleys act as barriers or may turn into bridges for dispersal, depending on the ecology of the species and the conditions in the valley” …read more on NOPR