(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
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