Figure 43.9: Finch Morphology Evolves in Response to Competition with Carpenter Bees On those Galápagos islands where small ground finches are the sole pollinators of small flowers, the birds are small (as measured by their short wingspans). Small size lowers their energy requirements and may increase their ability to negotiate the flowers. On islands where carpenter bees compete with these finches for nectar, the birds are larger and have bigger, stronger beaks (which allows them to include seeds in their diet).