A recent article published by in Current Biology revealed way that bees stay on the flower while collecting nectar: with a “Velcro-like surface”, according to team member Beverley Glover.
The UK team of scientists discovered that these flowers have specialized cells on their petals, shaped similarly to small cones or pyramids.
These cells were not a new discovery; researchers have long since recognized that most flowers had these on their surface, however no one knew their purpose.
In the study, the team tested the behaviour of the bees as they endeavored to feed off two versions of a Snapdragon: a mutated version of a Snapdragon lacking conical cells, and one with the cells. The purpose was to see if the bees would be able to recognize the shape of the petal shells, and discriminate between different surfaces.
On the flowers without the cells, the bees cannot land properly, making pollination difficult. The special cells provide a “Velcro-like” grip, and with the cells in tact, they can extract nectar more efficiently.
The team did find that when the flowers were at a horizontal angle, the bees visited both flowers about half of the time primarily because they didn’t have to land on the petals to get the job done. However, when the flowers were maneuvered to an angle, the bees quickly learned how to recognized the cone-celled flowers and landed on them about three-quarters of the time of the time.
This results in an explanation to the question of the why the cells exist and the prevalence of the coned-shaped cells on the petals in about 80% of flowering plants.
Journal information: Heather M. Whitney, Lars Chittka, Toby J.A. Bruce, and Beverley J. Glover. Conical Epidermal Cells Allow Bees to Grip Flowers and Increase Foraging Efficiency. Current Biology, 2009; DOI: 10.1016/j.cub.2009.04.051
Image courtesy of National Biological Information Infrastructure