argylesock says… The hummingbird hawk moth (Macroglossum stellatarum) is a summer visitor to us here in Britain. Just now the country is shrouded in snow, so it’s good to be reminded of the insects which we can expect to see flying soon.
The mutual benefits of insect pollinators to flowering plants has led to a wide diversity of insect pollinators and flowering plants for over 100 million years. Flowers are rewarded with more efficient use of their pollen, an expensive material to create, and insects are rewarded with sugar and other nutrients that increase their fecundity.
Arx and colleagues studied the fecundity and longevity of female hawk moths that were allowed to feed on nectar or denied nectar after mating. They found that feeding on nectar increased the longevity of the female hawk moths almost 2 fold. The numbers of eggs laid also doubled. Even though hawk moths consume large amounts of energy during flight, the rewards offered by the plants were greater than those losses. Sufficient rewards by the plants encourage the hawk moths to continue collecting nectar and pollinating flowers after they have mated.