|How does pollen protein concentration affect host plant choice and offspring development of pollinators?|
Pollen protein concentration (dry weight) based on samples
from 377 plant species in 93 families and 231 genera
Provisioning and developmental sequence for
Lasioglossum zephyrum in lab nests. Sequence
shows 1) Female collecting pollen; 2) Larva
consuming pollen/sugar water provision;
3) Pupae in brood chambers; 4) Emergent adults,
the larger reared on high protein (Solanum) pollen,
the smaller reared on low protein (Typha) pollen.
Pollen varies widely in protein concentration, from about 2.3% in Cupressus arizonicus to over 60% in Rhexia mariana and Dodecatheon clevelandii. Because pollen is the main source of protein and micronutrients for bees, this range has great potential implications for the development of offspring reared from different pollen sources. Lab work using the sweat bee Lasioglossum zephyrum has shown that protein concentration of pollen may dramatically influence offspring size. Body size has been correlated with many important fitness measures in different bee species and therefore pollen selection by adult bees may greatly influence the performance of their offspring. Currently, there are little data available to show whether adult bees select pollen based on the nutrient content of that pollen, despite these obvious implications.