When we think of pollination we imagine a honey bee foraging on a flower, collecting nectar or pollen, and inadvertently transferring some of the pollen to the next flower she visits.
I’ve always thought that solitary bees might be more efficient pollinators for several reasons. For example, solitary bees seem to fly faster between flowers, collect pollen more quickly, and take little nectar compared to honey bees. In addition, solitary bees carry their pollen in its natural fluffy state that is readily usable by flowers.
On the other hand, honey bees and bumble bees glue their pollen loads together with nectar, making a tightly-packed pellet that is useless for pollination. In fact, most of the pollen that honey bees transfer from flower to flower is stuck to their bodies in random places. When foraging on the next flower, some of this pollen rubs onto the stigma and pollinates the flower, but the pollen in the pellets doesn’t budge.
Other habits of honey bees make them excellent pollinators. Honey bees have amazing floral fidelity, a trait that keeps them visiting the same kind of flower over and over. Floral fidelity is a huge boost to pollination, but it is frequently absent in other bee species. When a single bee carries many types of pollen, she is less likely to deliver the right type to the next flower.
Image courtesy of honeybeesuite.com