1 . The Social Use of Space 97 



tion of artificial feeding has not disrupted the marked yarding tendencies 

 of Wisconsin deer. Through many generations they have developed a 

 culture demanding an excessive frequency of contact with others during 

 the winter season when they would otherwise be more scattered. 



I will freely grant that this interpretation of the origin of yarding may 

 be oversimplified. Nevertheless, available observations warrant considera- 

 tion of the concept of the behavioral sink as helping us understand the 

 historical development of yarding to an excessive degree. 



E. Concerning Basic Numbers, Nb, for Man 



During the past half million years, density of Homo sapiens has exhibited 

 a continued increase over the inhabited portions of the earth (Deevy, 

 1960; von Foerster et al, 1960) . Most who have concerned themselves with 

 studying such change restrict their emphasis to changes in density accom- 

 panying advance in extractive efficiency of natural resources. Less atten- 

 tion, even by anthropologists, has been devoted to determining sizes of 

 social groupings forming partially closed systems. Such partially closed 

 systems range from a male-female pair to that of a nation such as the 

 United States among which interactions among all members may be con- 

 ceived of in terms of population potential (Stewart, 1948; Calhoun, 1957). 

 It will not be my purpose here to treat the entire range. Rather, I shall 

 merely present a few highly selected examples of some of the smaller 

 groupings which presumably reflect evolutionary limitations to group 

 structure. On the assumption that these group sizes represent the conse- 

 quences of underlying basic forces, they will be used in later sections 

 (XIII, A and B) as data for developing a general formulation of group 

 size and social interaction. 



For about 98% of his history during the past half-million years, simple 

 food gathering limited man's economy and social life. One of the earliest 

 known settlements at the Star Carr site in east-central England of nearly 

 10,000 years ago consisted of five families, ten adults (Braid wood and 

 Reed, 1957) . Thus, it appears that an adult group size not diverging greatly 

 from my hypothesized ideal of 12 may have characterized the human 

 species up until at least 10,000 years ago. 



The Australian aborigines (Birdsell, 1953, 1957) provide further insight 

 into the basic numbers of human groups. In terms of the typical number of 

 adults, five levels are recognizable: (a) the family with 2 adults; (b) the 

 "horde" or extended family with 16 adults; (c) the supra-horde of 50 

 adults; (d) the tribe with 200 adults; and (e) the supra-tribe with 2200 

 adults. The horde forms the most basic social group, ranging generally 



