The Unity of Ecology* 



By F. Fraser Darling 



Vice-President, The Conservation Foundation, New York, N.Y. 



It is rather extraordinary to be asked by educated people, what 

 is ecology ? — the more so, as economics is a word used by everyone and 

 the substitution of the letter "e" for the diphthong "oe" disturbs no- 

 body. Both ecology and economics, so properly derived from the 

 Greek oikos — the home, are concerned with the ordering of the habitat 

 and income and expenditure. Both sciences deal with communities 

 and are, at simplest, observational studies of communities. Economics 

 has tended to deal with income and expenditure symbolized in money, 

 and the most dangerous economists have been those who have mistaken 

 the symbol for the reality. There is now a refreshing trend to con- 

 sider wealth as availability of resources, often natural and renewable 

 and organic resources. The changes in the status of availability are 

 subtle, depending on history, growth and movements of populations, 

 and on technology. The resources themselves change in economic 

 status with changes in human needs and desires, emergencies and 

 fashions. 



Ecology deals with income and expenditure in terms of energy cycles 

 in communities of plants and animals, deriving from sunlight, water, 

 carbon dioxide and the phenomenon of photosynthesis by which or- 

 ganic compounds are built. This raw definition is made more interest- 

 ing by what I would emphasize as the observational study of com- 

 munities of animals and plants. Here comes the possibility of that 

 more general definition of ecology as the science of organisms in rela- 

 tion to their total environment, and the interrelations of organisms 

 interspecifically and between themselves. The total environment in- 

 cludes all manner of physical factors such as climate, physiography 

 and soil, the stillness or movement of water and the salts borne in 

 solution. The interrelations of organisms and environment are in some 

 measure reciprocal in influence ; in animal life it is becoming increas- 



1 Presidential address delivered to Section D (Zoology) on August 29, 1963, at the 

 Aberdeen Meeting of the British Association for the Advancement of Science, and re- 

 printed by permission from Advancement of Science, November 1963. 



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