Benchmark 11C
Common Themes: Constancy and Change
Grades 9-12, page 275

Things can change in detail but remain the same in general (the players change, but the team remains; cells are replaced, but the organism remains). Sometimes counterbalancing changes are necessary for a thing to retain its essential constancy in the presence of changing conditions.
 

See the general discussion in Unifying Concepts and Processes: Systems, order, and organization and Evolution and equilibrium