How do bees cling to flowers?

Most flowers have cone-shaped cells on the surface of the petal. These help bees grip complicated flowers. These cone-shaped cells are also present on simple flowers, which should be easy for bees to land on.
When flowers move in the wind it makes them attractive to pollinating insects. Flowers can also move when an insect lands on them, if they are on a long stalk. "So we wondered whether conical surface cells also help bees to grip simple flowers when they are blown about in the wind or move in other ways.
To test this idea we used the simple flowers of the common garden plant Petunia hybrida, and buff-tailed bumblebees, Bombus terrestris. We offered bees in a flight arena a choice of normal Petunia flowers (which have conical cells) or mutant Petunia flowers with flat petal cells. The bees preferred the flowers with conical cells. We then tested whether this preference still held if the conical-celled flowers were a darker, less attractive colour, and found that in this case the bees preferred the flat-celled flowers. This result suggests that grip is not a very important factor for a bee handling a Petunia flower. However, when we simulated a windy day by making the flowers move on a rotating platform, the bees strongly preferred the conical-celled flowers, whatever their colour. Their preference for the extra grip completely overcame their dislike of the darker colour.
From these results we can conclude that cone-shaped surface cells are important even in simple flowers because they help bees to grip the petal in windy conditions. This result goes some way to explaining why almost all flowering plants have cone-shaped petal cells."
Thanks to Bees need better grip when flowers move
Beverley Glover, Katrina Alcorn and Heather Whitney

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