(1) AVALANCHES of perturbations, made up of "pockets" of co-evolutionary change and having
a characteristic relationship between size scale and frequency, may propogate thru an ecosystem.
This possibility requires some part of the ecosystem to be at rest while other parts change.

(2) THE PROPAGATING changes are likely to be associated with fluctuations to low fitness,
which may engender both extinction and speciation events. Extinction events would be expected because of low fitness and speciation events might be expected with low fitness because the
number of directions of of improvement is increasing and because isolated sub-populations
would form. If the probability of branching speciation is proportional to the number of directions of improved fitness, then low fitness episodes should trigger speciation events.

A computer simulation example of extinction

Complexity index