I realized that it would be helpful to have Holland's model here on the blog rather than needing to refer to the papers, so I've put a slightly shorter version of it here.
Properties of complex adaptive systems
Aggregation has two meanings. One is simplifying complexity by grouping items with similar characteristics, a primary method, Holland points out, by which we build models. The second meaning refers to how complex systems behave. Through the combined interactions of less complex agents, complex collective behaviors emerge. Consider the following levels of aggregations, their interactions, and their emergent behaviors: cells, organs, individual human beings, and social and institutional groups.
The differences in behavior at different levels is due to the property of nonlinearity. In nonlinearity, the behavior of the whole cannot be reduced to the sum of the parts. Obviously, the behavior of individual human beings cannot be understood simply by studying cells and organs, and similarly the behavior of complex educational systems cannot be understood by the behaviors of individual members, whether students, teachers, or administrators.
A third property of complex systems is flows. Flows refer to the movements of resources among agents via connectors that vary according to the system. For instance, in a food transportation system, the connectors are the transporting vehicles; the resources are the different foods; and the agents are the transmitting, storing, and receiving entities, such as farmers and grocery stores. The elements in a network change over time as agents adapt to various situations. In a second language writing framework, flows include the movement of rhetorical knowledge among students and teachers within and across classroom boundaries.
The final property is diversity. Educational institutions consist of many different types of teachers (science, English, history), staff members (janitors, secretaries), administrators, and students. Diversity results from complex systems because each agent’s niche in the system “is defined by the interactions centering on that agent" (Holland). This diversity is a dynamic pattern because agents engage in progressive adaptations via their interactions with other agents, thus constantly changing their niches in the system.
Mechanisms
The mechanism of tagging facilitates selective interactions and thus the formation of aggregates. Tags are identifiers and categorizers. They can be badges identifying people who work in a company, thus setting the boundaries of the aggregate. They can also be values that identify potential friends or mates for future interactions and screen out others. Tags, therefore, also influence flows because they almost always define the network by delimiting the critical interactions, the major connections.
A second mechanism is schemas, or what Holland calls internal models. Internal models are mechanisms for anticipating situations. Internal models develop from interactions with the environment through three steps: reproduction through fitness, recombination via cross-over, and replacement. If a schema is fit, that is, successful in anticipating situations and guiding behavior, it acts as a parent in reproducing new schemas. In recombination, parts of different parent schemas (i.e., building blocks, see below) cross over to each other and recombine to create, new offspring schemas. These offspring schemas can replace other schemas already in the population. If we translate these terms into composition classroom analogies, reproduction means that students continue to use schemas that work in their essays. Recombination refers to students incorporating, for example, new concepts of writing into their present concepts so that both old and new concepts are used in some hybrid form. Replacement refers to students replacing an older schema for writing with a new, usually hybrid, schema.
The final mechanism is building blocks. Holland gave the example of a human face, in which the common building blocks would include hair, forehead, eyebrows, eyes, and so on, up to ten blocks. He also broke each facial building block into ten alternatives (e.g., blue eyes, brown eyes, hazel eyes, etc.), which gave a total of 100 building blocks. If one were to choose one alternative building block from each of ten bags of facial components, there would be 10 billion distinct faces with only 100 building blocks.
Another example would be the four bases of DNA. Various permutations of these four building blocks have given rise to myriads of species, all uniquely adapting to and fitting their environmental niches. When applied to composition, Holland’s model of building blocks differs from those in which teachers “transmit” a static blueprint of writing to students who, in turn, learn to assemble various components in a linear, lock-step manner toward a predetermined product. Rather, in Holland’s model, the focus is on interactions, adaptation, and emergence. Like DNA, interactions between rhetorical building blocks and social environments generate species of arguments, each one adapting to social niches, such as political speeches, academic articles, newspaper editorials, and family squabbles. Thus, the interactions of a few building blocks can generate novelty and, as will be seen, learning.
As per the entry, below, it is the interactions of building blocks that I am looking at right now. Are there a few building blocks that can give theoretical rise to a coherent model of rhetoric for students in first-year composition, a model that they can take with them and transfer to new situations?