The articles DOES mention that. 150 is part of an "hierarchy" of sorts of numbers. Roman army example: The basic infantry fighting unit was a group with 120

The articles DOES mention that. 150 is part of an "hierarchy" of sorts of numbers. Roman army example: The basic infantry fighting unit was a group with 120 men, that during formation-based battles (not all battles were like that) organized themselves in 40 columns and 3 rows. This was called a "maniple" and was led by a "Centurion" (cent of centurion means one hundred). Inside that group it was normal to have smaller groups of various sizes (having subleaders for 60 men was common for example, and sometimes for 30 too), and informally thre was one guy leading each group of 6 or so people. With cavalry stuff was similar ,but more formal, the centurions led "decurions", each "decurion" had 10 men under him. the Decurions were a formal position, but elected, chosen by their own men. Then 3 decurions were chosen to work in a group, one of them was the leader, and 2 of them auxiliaries, during battles the leader could lead all 30 men, or if needed the trio could split into 3 groups of 10. Thing is, all that still matches Dunbar's calculations more or less, and this is mentioned in the article, for example the reason humans limit all-to-all to 3-6 people is because that is how far you can get your voice in a noisy environment.