Fig. 5.

Hypothesized effect of flower (stamen) mass on the accelerations achieved by an individual bee. A bee of certain mass (m_bee) and characteristics should be able to generate a given maximum force (f_bee) using the acceleration (a_bee) of its thoracic power muscles (f_bee=m_bee×a_bee). When the bee applies these vibrations to the flower, the mass of the flower (m_flower) is added to the bee–flower coupled system, decreasing the acceleration proportionally to the mass of the flower. A bee visiting a flower with relatively smaller stamens (A) should achieve higher anther accelerations than the same bee visiting a flower with larger stamens (B). The positive relationship between anther acceleration and pollen release then predicts that, all else being equal, the rate of pollen removal should also decrease with flower mass.