Although this author's (R.L.H.) disagreements with Harry Jerison are legion (e.g. Holloway, 1966,1974,1979), I have always found his ideas stimulating and thus of great value to my own work regarding human brain evolution. I believe we best honor Harry Jerison by taking his ideas seriously, whether or not we agree with them.

There do not appear to be any serious disagreements that the brain became reorganized as well as enlarged during hominid evolution, but there is considerable controversy as to when reorganization, particularly that relating to the reduction of primary visual striate cortex, Brodmann's area 17, had taken place. (Reviews of these questions can be found in Holloway, 1995, 1996.) Since the only way we will ever know for absolutely certain when this process occurred requires travel with a time machine and some histological sectioning of australopithecine brains, one might wonder why we are writing this paper. It is already apparent from the literature on early hominid brain evolution that a major controversy exists regarding the fossil australopithecine endocasts and their interpretation regarding that infamous landmark, the lunate sulcus. Falk (1983, 1985, 1986) interprets the paleoneurological evidence from the Taung and Hadar (AL162–28) endocasts as indicating that the lunate sulcus was in an anterior pongid-like position. Holloway (1981, 1983, 1984) interprets the evidence as suggesting a posterior, more modern-human like position.