Chimpanzee/human technological differences are vast, reflect multiple interacting behavioral processes, and may result from the increased information-processing and hierarchical mental constructional capacities of the human brain. Therefore, advanced social, technical, and communicative capacities probably evolved together in concert with increasing brain size. Interpretations of these evolutionary and species differences as continuities or discontinuities reflect differing scientific perspectives.

Wilkins & Wakefield fall short of solving the language origin puzzle because they underestimate the cognitive and linguistic capacities of great apes. A focus on ape capacities leads to the recognition of varied levels of cognition and language and to a gradualistic model of language emergence in which early hominid language skills exceed those of the apes but fall far short of those of modern humans or later fossil hominid groups.