b. J. GrinnelP originated the niche concept with his description of the niche of the 

 California thrasher ( Toxostoma redivivum). Three classes of environmental 

 factors were significant. Zonal factors included chapparal vegetation, temper- 

 ature, altitude, slope, exposure and humidity. Associatlonal factors were 

 evergreeness, height, cover and vegetation. Faunalfactors referred to migration. 

 Of these factors Grinnell wrote, "These various circumstances, which emphasize 

 dependence on cover and adaptation in physical structure and temperament 

 thereto, got to demonstrate the nature of the ultimate associational niche 

 occupied by the California thrasher." C. Elton' had a functional orientation for 

 the niche, but it did not go beyond direct factors: "It is. . .convenient to have some 

 term to describe the status of an animal in its community, to indicate what it is 

 doing and not merely what it looks like, and the term used is 'niche.' *** the 

 'niche' of an animal means its place in the biotic environment, its relations to 

 food and enemies.^' G. E. Hutchinson-' defined the fundamental niche of an 

 organism as a direct factor hyperspace bounded by upper and lower limits of 

 physical and biological variables permitting "indefinite existence" or "persis- 

 tence" in an ecosystem. His realized niche referred to conditions in the ecosystem 

 in terms of the same factors which form the axes of an organism's fundamental 

 niche. Niche in ecology traditionally ignores indirect factors. Vandermeer' 

 considered Hutchinson's fundamental niche to be preinteractive, its axes 

 restricted to abiotic variables. Partial niches (postinteractive) are defined as 

 species are added to an assemblage. Whether the extant species interact directly 

 or indirectly is not considered, but each empirically defined partial niche of an 

 organism as a function of all species present at least leaves open the possibility of 

 indirect interactions between them. Recently. Levine^ has made this possibility 

 explicit in his extended niche concept which represents the beginning of 

 movement away from the classical direct factor niche (see also. References 7 and 

 8). 



c. it has become stylish to attribute purposeful activity to improbable biological 

 objects, as indicated by a sampling of recent titles from The American Naturalist, 

 113-114(1979) and 115-116. No. 2 ( 1980. current issue): "Long- and short-term 

 dynamic optimization models with application to the feeding strategy of the 

 logger head shrike." "Classifying species according to their demographic 

 strategy. . .," "Alcoholic fermentation in swamp and upland populations of 

 Nyssa sylvatica: temporal changes in adaptive strategy," "A note on the 

 evolution of altruism in structured demes." "The origin of the 'adaptive 

 landscape' concept," "Is a super territory strategy stable?," "The evolution of 

 sex-ratio strategies in Hymenopteran societies. ""The strategy of the red algal life 

 history." "Barking in a primitive ungulate, Muntiacus reevesi: function and 

 adaptiveness," and "Enzyme polymorphism and adaptive strategy in the 

 decapod Crustacea." Waddington's The Strategy of the Genes'^ and Dawkins' 

 The Selfish Gene^^ are a delight as metaphors, but in population and 

 evolutionary ecology metaphor is not always very distinct from explanation. 



d. Ecological psychologists have written against this dualism in favor of organism- 

 environment synergy. The organism and its environment are a unitary whole, 

 mutually compatible, complementary and co-implicative."''-''^ 



e. The ecosystem model is under development by Ecology Simulations. Inc.. 

 Athens. Georgia, for the National Oceanic and Atmospheric Administration of 

 the U.S. Department of Commerce (Contract No. NA-79-SAC-00790). Its 

 purpose is brine impact assessment in the northwestern Gulf of Mexico as part of 

 the Strategic Petroleum Reserve Program. The model's authors are M. Craig 

 Barber. Susan L. Durham, Randall E. Hicks, and Elizabeth F. Vetter. The 

 present version consists of the following major functional compartments, each 

 containing one or more levels of subcompartments. The Plankton groups are: 

 Nannophytoplankton and Net Phytoplankton. which are obligate autotrophs; 



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