Pollen in Bee‐Flower Relations Some Considerations on Melittophily*

Abstract

Abstract:Pollen and nectar are usually lumped together as floral rewards for pollinating bees, but they play totally different roles for flowers and bees (Table 1), as well as in the relationship between them. While flowers are specialized for certain pollinators via nectar, bees specialize on certain flowers via pollen. While flowers need pollen as a prerequisite for pollination, it is the essential larval food in bees. Thus, there is a strong competition between them for pollen. Foraging for pollen must be divided into three phases: uptake in the flower, reloading into and homeward transport within a carrying container. Bees have specializations for transport but hardly any for pollen uptake ‐ and thus for pollination. Bees actively harvesting pollen usually do not pollinate. This only happens as a consequence of contamination of the bee by pollen. From these data a scenario is provided for the evolution of bees and bee flowers. Specialized bee flowers are often characterized by their ability to hide pollen from the bees and at the same time use them as optimal pollinators. If the relationship of bees and flowers is mutualistic at all it is best described as a balanced mutual exploitation.