Some flowers have petals covered in tiny cells like pyramids and scientists have discovered that the purpose of these conical structures is to help bees get a good foothold. In order to discover this the researchers created very convincing artificial flowers from epoxy resin, making some with cones and some without. A sugar solution was placed inside and bumble bees were set free in the laboratory to ascertain their preference.
When the flowers were horizontal the bees showed no particular inclination, treating coned and coneless flowers impartially. However, when the flowers were angled the bees preferred the rough surfaces to the smooth and more so as the angles grew steeper. High-speed film showed that on the smooth petals the bees’ feet were unable to gain a good purchase and they were having to beat their wings fast to maintain their position, using a great deal of energy in the process.
In a separate study the pyramidal cells were found to act like solar panels, warming the petals and the nectar which benefitted the bees, allowing them to use their energy for their prime purpose of collecting nectar and pollen.
In the following photographs there are different species of bees. Bee identification is not one of my skills so I am unsure of naming them correctly!
White-tailed bumble bee - Bombus lucorum - on Chives
Bombus lucorum again
Honey bee - Apis mellifera - on flowers of Physocarpus Opulifolius (Common Ninebark) 'Dart's Gold'
Bumble bee - Bombus terrestris? - on Common Ninebark flowers
Buff-tailed Bumble bee - Bombus terrestris - on Herb-Robert