Population Ecology (also called organizational ecology) is a branch of evolutionary organizational theory developed by Hannan & Freeman in 1989 in their book "Organizational Ecology."
Using the analogy of Darwinian evolution, Hannan & Freeman investigate founding rates and death rates of organizational populations, and suggest that the rates are density-dependent. The expectations are:
1) The relationship between density and mortality rates is U-shaped.
2) The relationship between density and founding rates has an inverted U-shape.
These expectations are derived from the following four assumptions, or building blocks:
a) Organizations develop routines which ensure reliability and accountability.
b) Reliability and accountability require organizational structures that are highly reproducible.
c) This reproduction of routines that are almost similar is the cause of organizational intertia. Intertia is considered a consequence of selection.
d) The environment will select organizations with high intertia.
Expectation 1 can be explained like this: At first, when the density of organizations within a new niche is low, legitimacy is also low, because routines for reliability and accountability has not yet been developed high mortality rates (who do you trust the most: Microsoft or a new company who has just released a new alternative program?). After a while, as legitimacy rises, mortality rates are reduced. But as the density increases, competition becomes so fierce that the mortality rate again starts to rise.
Expectation 2: At first, when legitimacy is low (and uncertainty and the mortality rate is high), the founding rate is low. After a while, when the legitimacy rises, the nice becomes more attractive, and the founding rate rises. But, as in no. 1, as competition becomes fierce because of high density, the niche becomes less attractive, and the founding rate is reduced.
A balance is found at the niche's "carrying capacity."
There has been some empirical work to investigate these relationships, and the results have been inconclusive. This view may vary, however.
Population ecologists are using the analogy of Darwinian evolution, and are therefore prone to the same problems as Darwinian evolution in biology. In addition, intentionality and human agents seem to play a more significant role in organizational development than in biological evolution. Design theory can have interesting applications to organization theory in general, and also in population ecology.
Web Resources On Population Ecology
Evolutionary Theories in the Social Sciences
Book Resources On Population Ecology
Organizational Ecology by Hannan & Freeman
'Organizational Ecology' in: Handbook of Organization Studies (Clegg et al.) by Baum, J. A. C.
Organizations Evolving by Howard Aldrich
Editor(s): Anders Ohm