Horn of Africa covered the Simien and Bale Mountains but melted at the beginning of the Holocene. The mountains descend in a huge escarpment to the Red Sea and more steadily to the Indian Ocean. Socotra is a small island in the Indian Ocean off the coast of Somalia. Its size is 3,600 km (1,390 sq mi) and it is a territory of Yemen. The lowlands of the Horn are generally arid in spite of their proximity to the equator. This is because the winds of the tropical monsoons that give seasonal rains to the Sahel and the Sudan blow from the west.
Horn of Africa Cinnamonifora due to the aromatic plants, or Regio Incognita owing to its unchartered territory. Shell middens 125,000 years old have been found in Eritrea, indicating the diet of early humans included seafood obtained by beachcombing. According to both genetic and fossil evidence, archaic Homo sapiens evolved into anatomically modern humans solely in the Horn of Africa between 200,000 and 100,000 years ago and have dispersed from the Horn of Africa. The recognition of "Homo sapien idaltu" as a valid subspecies of the anatomically modern human lineage would justify the description of contemporary humans with the subspecies name "H. s. sapiens".