The fossilized remains of "H. s. idaltu" were discovered in Ethiopia's Afar Triangle in 1997. The region has volcanic layers. By using radiometric dating, the layers date between 154,000 and 160,000 years old. Three well preserved crania (top part of skulls) were discovered, the best preserved being from an adult male (BOU-VP-16/1) with a brain capacity of . 