694 



ECOLOGY AND EVOLUTION 



society has many supraorganismic char- 

 acteristics. Cannon (1941) said, "The body 

 politic exhibits many processes which re- 

 semble those found in the body physiologic; 

 the analogies are so close and so numerous, 

 not only for nations but also for industry, 

 as to intimate strongly that there are in- 

 deed general principles of organization, 

 widely applicable to complex aggregations 

 of collaborating parts." As in the nonhuman 

 species, the integrated cooperative group 

 may be an important unit of selection, so 

 that survival may well be in relation to 

 humanity as a whole, rather than for the 

 benefit of the few at the expense of the 

 many. Sacrifice by some individuals for the 

 good of the group, and sacrifice by some 

 infraspecies groups for the good of the 

 species, are exhibited in both biological 

 and social systems; thus many ethical 

 principles have a biological foundation 

 (Gerard, 1942a; Allee, 1943). 



As in the evolution of nonhuman popu- 

 lation units, the benefits to the whole sys- 

 tem is not independent of the benefit to 

 the individuals composing the group. The 

 surviving system in all probability will be 

 neither one in which the group exploits the 

 individuals composing it, nor in which the 

 individuals exploit the group. Rather, it 

 may be expected that surviving populations 

 will be coordinated under the formula "one 

 for all and all for one." 



Lest the concept of the evolution of the 

 biological supraorganism be used to advo- 

 cate totalitarianism, either of the fascist or 

 communist type, we sound a note of warn- 

 ing. The social unit, whether a class, a 

 tribe, a nation, or the species as a whole, 

 has probably evolved somewhat as the 

 biological population has: through a certain 

 degree of variation, selection of favorable 

 variations in relation to both the environ- 

 ment and to the organismic system, and 

 transmission of the surviving variations to 

 succeeding generations. Whether human 

 social evolution moves toward autocracy, 

 fascism, communism, or democracy prob- 

 ably depends upon how these political 

 systems influence the primary factors of 

 social fimctioning, including, of course, 

 social evolution. Variation may be analo- 

 gized with the creative arts and sciences, 

 natural selection with social selection 

 through optimal competition, and germinal 

 heredity with transmission through sym- 



bolic communication of cultural patterns 

 (social heredity). Animal and plant breed- 

 ers have improved varieties through the 

 application of evolutionary principles. 

 Through the application of intelligent "arti- 

 ficial" selection of social units, human 

 social evolution could also advance more 

 rapidly toward greater function, greater 

 integration, and more effective control over 

 the environment (Cannon, 1941). Elimina- 

 tion of nonconformists may destroy the de- 

 gree of social variability upon which pro- 

 gressive social evolution depends (see Mul- 

 ler, 1948). 



In resume, the generalizations of this di- 

 vision lead to the broad conclusion that 

 selection operates on parts and wholes of 

 genetically connected intraspecies popula- 

 tions (i.e., on species, cyclomorphic popu- 

 lations, aggregated populations, sex pairs, 

 family units, and on societies) in a man- 

 ner similar to the action of selection 

 on protoplasmically connected organisms 

 (Weismann, 1893, p. 327). Efficient func- 

 tional coordination within each unit is 

 comparable to the adjustment of the unit 

 as a whole to its surroundings. Adaptation 

 toward a balanced relationship and internal 

 relative constancy (homeostasis) has ob- 

 viously developed within each system dur- 

 ing phylogeny, and the more inclusive 

 systems incorporate, at least in partial or 

 modified form, the external environment of 

 those less inclusive. 



Populations, however, are usually far 

 more loosely integrated than are protoplas- 

 mically continuous organisms. Even the 

 social insect supraorganism is more soundly 

 analogized with a primitive multicellular or- 

 ganism such as a sponge, than with a 

 highly complex coordinated vertebrate or- 

 ganism. 



SUMMARY 



A number of broad conclusions may be 

 drawn from this discussion of the role of 

 natural selection. Natural selection of 

 genetic variations is the primary guiding 

 factor directing evolution toward increased 

 endoadaptation and exoadaptation. Chance 

 genetic variation, chance dispersal, and 

 orientation behavior may enable preadapted 

 forms with genetically simple new adaptive 

 modifications to become established in new 

 habitats where natural selection in time will 

 develop more complex adjustments. The 



