Hysteresis


A good friend of mine just introduced me to the idea of hysteresis, which fits very well with our “school as ecosystems” framework. Essentially, hysteresis refers to the impact that a system’s history has upon its condition. The good folks at wikipedia provide an example:

“Coral reef systems can dramatically shift from pristine coral-dominated systems to degraded algae-dominated systems when populations grazing on algae decline. The 1983 crash of urchin populations in Caribbean reef systems released algae…allowing them to overgrow corals and resulting in a shift to a degraded state. When urchins rebounded, the high (pre-crash) coral cover levels did not return, indicating hysteresis .”

This is a hysteretic effect: despite the fact that some elements (the urchins) in an ecosystem (the Caribbean reefs) had returned to previous levels, the ecosystem’s history prevented the system from returning to its prior state. Phew.

Among other things, the concept of hysteresis should give us all caution. When we alter a system of any kind, the effects may be irreversible, or not reversible in the short term. For example, when we close down public schools by the dozen, then later find out that our system for rating schools bears no relation to the actual student learning, we might not be able to undo the damage.

There’s the damage we do to students, whose social and emotional (not to mention academic) experiences of school may be severely disrupted by school closures. There’s the damage we do to educators, whose efforts to build their school communities are discarded like so much city trash. Perhaps most importantly, there’s the damage we do to communities all over the city, where students and their parents learn that their voices do not matter, even when the decisions being made affect them most.

Advertisements

2 thoughts on “Hysteresis

  1. Will, this is a fascinating concept I'd like to learn more about. It points to a critical distinction between sterile machines and dynamic living systems, and the extreme caution we must take when attempting to alter the conditions of the latter.

    If we consider a school community as a dynamic living system, any changes we make to that system must account for the specific conditions of that community.

    This leads to a further question: when damage has already been done to a community, and hysteresis is evident, is it possible to restore prior relationships or cultivate positive new ones through ecological interventions?

    Like

  2. My understanding is that when hysteresis (or a hysteretic effect, I'm still learning the proper terminology) is present, prior relationships can be restored, but not always. It depends on the severity of the changes or damage done to a particular system. My guess is that reversing hysteretic effects takes a long time, so this points to another one of our key ideas: school reform or repair requires a long-term perspective. We can't expect quick results when working with complex systems.

    Like

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s