Two different but closely related orchards have red and yellow flowers. Red flowers attract more pollinators than
do yellow. However, the stamens within the yellow orchards have a higher pollen count. These species have a recent common ancestor, but do not crossbreed.
What prompted the gradual change in phenotypes?
a. reshuffling of the alleles of the dominant gene
b. random mutations that changed the genome of an individual
c. availability of a new ecological niche and speciation
d. reproductive success of different variants within each orchid