Chapter 4 - Ecosystems and Social Systems as ComplexAdaptive Systems
• Ecosystems and social systems are complex adaptive systems
o complex b/c they have many parts and many connections between the parts
o adaptive b/c their feedback structure gives them the ability to change in ways that promote
survival in a fluctuating environment
• emergent properties: the distinctive features and behavior that ‘emerge’ from the way that complex
adaptive systems are organized
o Stability domains.
o Complex system cycles
• Biological systems have a hierarchy of organizational levels that extends from molecules and cells to
individual organisms, populations and ecosystems.
o emergent properties- characteristic behaviors which emerge at that level; function
synergistically at each level of organization to give that level a life of its own which is greater
than the sum of its parts
Because the parts are interconnected, the behavior of every part is shaped by feedback
loops through the rest of the system.
Positive and negative feedback promotes growth and change in the system as a whole.
• Emergent properties are easiest to perceive in individual organisms.
o Ex. With jellyfish - basic emergent properties = growth, development of different tissues and
organs, homeostasis, reproduction and death.
o Richness of expression of emergent properties increases with the complexity of the organism
Ex. Vision and the perception of color are emergent images
o Emotions such as fear, anger, anxiety, hate, happiness and love are also emergent properties.
o Examples of emergent properties at the population level of organization= The sigmoid curve for
population growth, population regulation, genetic evolution and social organization
• The food supply for each species depends on
o the ecosystem’s biological production
o the amount of the ecosystem’s biological production that the food web channels to that particular
• Emergent property of ecosystems and social systems = counterintuitive behavior
o Counterintuitive behavior - the opposite of what we expect
Ex. construction of public housing in the United States during the decades after World
• Was supposed to reduce poverty by providing decent housing to low-income
families that they could afford ▯ people to move to cities even if their weren’t jobs
▯ public houses where turned into ghettos of poverty
Ex. Forest managers trying to reduce fire damage by putting out fires, but the result was
even more damage
o Ecosystems and social systems are sometimes counterintuitive b/c they are not easily understood
by people whose main existence is at a different level of organization - the level of an individual
inside the ecosystem and social system.
Explains why we can’t predict ultimate consequences of our actions
• Emergent Properties of Social Systems
o Distortion of information
Ex. Telephone game o Denial – refusal to recognize or accept the truth when it conflicts with existing beliefs
ex. Blaming small-scale peasant farmers for deforestation even though they usually use
resources in a good way
ex. 1950s and 2960s – ecologists warned public about the impending dangers of
population growth and environmental ruin… people denied it through decades and many
o ex. of emergent properties in human social systems through bureaucracies:
not effective in dealing with unusual situations
often do things contrary to their mission for the sake of survival
• Ecosystems organize themselves by means of an assembly process resembling natural selection.
• Biological community- all the plants, animals, and microorganisms living in an ecosystem
o Can be joined by new species if their births exceed deaths (while their population is small)
• Community assembly- process selecting species from a larger pool of species living in the surround