Bee Pollination

Bees are extremely successful pollinators for a number of reasons. They depend on flowers for both nectar and pollen and will therefore actively forage for pollen, resulting in better transfer between plants. Bees also have various morphological features which enable them to efficiently transfer and collect pollen. Each leg has a pollen brush made up of branched hairs on the first tarsal segment (tarsomere). The pollen brushes on the prothoracic legs collect pollen from the front of the body, the brushes on the mesothoracic legs collect pollen from the thorax and prothoracic legs and the brushes on the metathoracic legs collect pollen from the mesothoracic legs. The prothoracic legs also have an 'antenna cleaner' - a notch on the leg that holds the antenna while the pollen is wiped from it.

In addition to pollen brushes, the metathoracic legs also have a pollen packer or pollen press which consists of a stiff spine located between the tibia and the first tarsomere. The bee uses the spine on one leg to remove the pollen from the pollen brush on the opposite leg. After a series of intricate manoeuvres the pollen is then transferred to the pollen basket, located on the outer surface of the tibia. The entire procedure is somewhat similar to a production line - pollen starts at the front and moves along the bee, being passed from leg to leg until it reaches the pollen basket.

This complex manipulation of pollen is carried out by the bee in the interval it takes to move from flower to flower (remember, the bee is also flying while it does all of this!).

As an interesting aside, the photo above shows a honeybee pollinating a red flower. Honeybees are unable to detect red but they are able to detect ultraviolet and so any red flowers that are pollinated by bees will be ultraviolet as well.

Photos courtesy of Peter Chew