Discuss gradualism and punctuated equilibrium as ideas about the pace of evolution.

gradualism is the slow change from one form to another;
requires long periods of time with relatively constant rate of change;
with punctuated equilibrium short periods of rapid evolution occur followed by long periods without change;
punctuated equilibrium fits with sudden environmental change/violent environmental conditions/volcanic eruptions/meteor impact;
in punctuated equilibrium, adaptations needed to cope with new environmental conditions/directional selection;
fossil record does not support gradualism / mass extinctions support punctuated equilibrium;
if no change in environment, then natural selection would oppose changes in gene pool;

Good candidates were able to get three of the four marks available for a discussion of gradualism and punctuated equilibrium. Again, many candidates were only able to get one or two marks for actually describing the two rather than discussing them which requires a range of arguments for or against an idea such as the fact the fossil record does not support gradualism and mass extinctions support punctuated equilibrium.