Let's think more about the extent and pace of plasticity in social organization by considering an example: hospitals. Hospitals are complex social organizations geared towards providing health care for moderately to very needy patients. And the internal organization of hospitals provides a fertile locus for examining issues of institutional change.
The complexity of a hospital derives from numerous factors: the specialization of medical knowledge (resulting in numerous departments), the multiplicity of business functions (billing, marketing, finance and budget, supervision of doctors, nurses, pharmacists, support staff), the logistical demands of patient care (food, medications, room and bed cleaning), social work needs of patients and families, the regulatory environment, governance institutions, and communication to the public, simply to name the most obvious functions. So a hospital requires the coordinated efforts of hundreds of experts and perhaps thousands of skilled and semi-skilled workers, embodying tens or hundreds of functions. (A mid-sized regional hospital employs several thousand people.)
Diversity and plasticity comes into this story in several ways. At the mid-level of analysis there are alternative ways of organizing the various functions of the hospital--different ways of organizing human resources, billing, or patient services. That is, structure is underdetermined by functional needs. There are organizational alternatives, and we can expect that there will be actual variation in hospital organization and implementation across the US health system.
This variation can be observed at a range of scales: within a region (Atlanta), across regions (Atlanta versus Detroit), or throughout the national system (midwest versus Pacific coast). At the most macro-level, we may observe differences in organization across national systems--US versus Germany or China. (Frank Dobbin's Forging Industrial Policy: The United States, Britain, and France in the Railway Age explores this sort of national-level comparison in application to technology policy frameworks in three countries.)
But diversity may also be observed over time at the level of the individual hospital. This is sometimes described as "organizational learning"--internal reorganization and redesign so as to better serve patient and business needs in a changing environment. Plasticity comes in here: the organization "mutates" in response to changing needs and new environmental challenges. (Consider some of the ways that hospitals will change as a result of new public reporting requirements concerning cost and morbidity.)
This mutation may be the result of deliberate choice on the part of hospital administrators (redesign of process). But it may also be the result of broader societal changes leading to changing behavior within the hospital, eventually leading to a change in the routine practices and organizations of the hospital. For example, the operating room of the US hospital of the 1990s is a social space governed explicitly and implicitly by the surgeon (usually male). But imagine the result of a broad values shift towards greater gender equality and less respect for hierarchical authority. We might expect a gradual shift in the operating room towards a team-based approach to surgery. That approach might be confirmed by a record of greater safety (as safety experts in fact expect). And the change might become entrenched in new formal operating rules and procedures--thus changing the institution for a while.
These arguments show the impulse towards differentiation across hospital structures. There is also an important "centripetal" force that works towards convergence to some degree. This is the process of imitation and the search for "best practices". Consultants are summoned; " how are other hospitals handling this problem of IV infections?" And successful efforts are imitated.
This example suggests a process of mutation, differentiation, imitation, and occasional convergence. Overall, it supports the vision of institutions as plastic and malleable and responsive to changing individual and societal needs.