DISCUSSION
This exercise provides an opportunity for
Part Two: Foraging after an environmental
change results in unequal availability of different
sized seeds
Now consider a scenario where there is an
environmental change (a severe warming in the
climate over several years) resulting in a drought.
The drought causes a decline in seed production,
particularly for small seeds. For the two largest seeds,
the seed availability declines, leaving ¾ cup of each
of these seed types in the environment. For the two
smallest seeds, the seed availability declines to a
greater extent, resulting in 1/8 cup of each of these
seed types in the environment. This situation is
analogous to the environmental change noticed by
Peter and Rosemary Grant while researching
Darwin’s Finches. The Grant’s observed a severe
drought in 1977 resulting in a drastic decline in seed
production with small seeds being particularly
affected (Grant, 1999; Boag & Grant 1981).