No clue what it means by "early man vocab" but here's a few technical ones: I = Ibrahim Shah, S.M. - Co-discoverer of a specimen in Pakistan dated 8 millions years ago (8mya) called Sivapithecus indicus. J = Johanson, Donald - American archaeologist renowned for his discovery of Lucy, a female hominid australopithecine in the Afar Triangle of Ethiopia. (everyone should know about Lucy, and shame on whichever witless museum that decided to sponsor its "travelling exhibition", long story here, but if anyone's interested, give me a shout and I can provide some juicy retarded details on it) Source: not sure where. K = Kebara 2 - A specimen named after its site of discovery, Kebara Cave, Israel. Or K = Krapina - again, specimen named after its site of discovery, Krapina Cave, Coratia. Can't help with X and Y, kind of braindead on those -sweat