A Skull of very early human ancestry called "Homo heidelbergensis" dating between 200,000 and 300,000 years old with Exhibit Item Number "Eliye Springs ES11693" can be found at the Smithsonian Institution.

In a preliminary report (Brauer & Leakey, 1986), the new fossil cranium KNM-ES-11693 from Eliye Springs at the western shore of Lake Turkana was presented as a further representative of archaic Homo sapiens : "The specimen comes from reworked deposits which exclude its being stratigraphically located. However, in spite of the dating problems, the well preserved and heavily mineralized fossil exhibits many morphological features by which it can be assigned to archaic Homo sapiens".

ES-11693 is compared to African early and late archaic Homo sapiens. Although the new hominid presents a unique mosaic of archaic and modern features, it appears to have a closer relationship with the late archaic H. sapiens grade, in which such hominids as Omo 2 and Laetoli H. 18 can also be grouped.