Fig 3. Percentage of overlap between the chimpanzee BA44 and functional subdivisions of the human BA44 [17,36–38].

Action-related regions present the highest overlap with action-related areas and virtually no overlap with the syntax area. The chimpanzee BA44 atlas was thresholded at 0.5 to maintain only its core area. The functions being reported are those with the highest P (Activation | Domain) as reported by Clos and colleagues [36] and Papitto and colleagues [17], except Clos 1, which was originally reported to be a syntax area, but further studies did not find to be involved in basic syntactic operations [36,37]. The underlying data and scripts used can be found in the GitHub/Zotero repository, under the scripts/ and results/human-comparison folders.