  We show that a cut-and-paste model to mimic a trial-and-error process of
adaptation displays two pairs of percolation and depinning transitions, one for
persistence and the other for efficiency. The percolation transition signals
the onset of a property and the depinning transition, the growth of the same
property. Despite its simplicity, the cut-and-paste model is qualitatively the
same as the Minority Game. A majority cut-and-paste model is also introduced,
to mimic the spread of a trend. When both models are iterated, the majority
model reaches a frozen state while the minority model converges towards an
alternate state. We show that a transition from the frozen to the alternate
state occurs in the limit of a non-adaptive system.
