Līdz šim nezināju par t.s. Danbāra skaitli: https://en.wikipedia.org/wiki/Dunbar%27s_number

"Primatologists have noted that, due to their highly social nature, primates must maintain personal contact with the other members of their social group, usually through social grooming."

un šādā kontekstā:

"Dunbar [..] proposes furthermore that language may have arisen as a "cheap" means of social grooming, allowing early humans to maintain social cohesion efficiently."