Final answer:
Kamoya Kimeu discovered a piece of skull at the Nariokotome site near Lake Turkana, which belongs to the Homo ergaster specimen known as the Nariokotome Boy.
Step-by-step explanation:
Kamoya Kimeu, a renowned fossil hunter, discovered a significant piece of skull on the west side of Lake Turkana at a site known as Nariokotome. This discovery is famously associated with the Homo ergaster specimen named the Nariokotome Boy, believed to be the remains of a boy around 12 years of age at the time of death. Kimeu's contributions to paleoanthropology are considerable, having played a pivotal role in uncovering critical evidence of human evolution.