left and Right Brain - Sulcus?
Possibly the left and right hemisphere is the primary and initial sulcus where the surfaces first sought close proximity.
Then over time as the brain developed more and more were formed. These obviously were less in scale, but still show the ongoing desire to create a binary and localised initial processing of information.
If you buy into the concept that the left and right brain assess different perspectives and combine to create the optimal solution then it’s highly likely that this method is carried out elsewhere in the brain, which points to the sulcus concept eluded to above.
(I am a big believer in scalability and uniformity in design of biological systems - complexity is achieved through iterations).
iNTj (Mastermind) 8w7 (Maverick)